# The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete
Release of MaNGA, MaStar and APOGEE-2 Data

Abdurro’uf11affiliation: Academia Sinica Institute of Astronomy and
Astrophysics, 11F of AS/NTU, Astronomy-Mathematics Building, No.1, Sec. 4,
Roosevelt Rd, Taipei, 10617, Taiwan , Katherine Accetta22affiliation:
Department of Astrophysical Sciences, Princeton University, Princeton, NJ
08544, USA , Conny Aerts33affiliation: Institute of Astronomy, KU Leuven,
Celestijnenlaan 200D, B-3001 Leuven, Belgium , Víctor Silva
Aguirre44affiliation: Stellar Astrophysics Centre, Department of Physics and
Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C, Denmark ,
Romina Ahumada55affiliation: Instituto de Astronomía, Universidad Católica del
Norte, Av. Angamos 0610, Antofagasta, Chile , Nikhil Ajgaonkar66affiliation:
Department of Physics and Astronomy, University of Kentucky, 505 Rose St.,
Lexington, KY, 40506-0055, USA , N. Filiz Ak77affiliation: Department of
Astronomy and Space Sciences, Erciyes University, 38039 Kayseri, Turkey ,
Shadab Alam88affiliation: Institute for Astronomy, University of Edinburgh,
Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK , Carlos Allende
Prieto99affiliation: Instituto de Astrofísica de Canarias (IAC), C/ Via Láctea
s/n, E-38205 La Laguna, Tenerife, Spain 1010affiliation: Universidad de La
Laguna (ULL), Departamento de Astrofísica, E-38206 La Laguna, Tenerife Spain ,
Andrés Almeida1111affiliation: Department of Astronomy, University of
Virginia, Charlottesville, VA 22904-4325, USA , Friedrich
Anders1212affiliation: Leibniz-Institut fur Astrophysik Potsdam (AIP), An der
Sternwarte 16, D-14482 Potsdam, Germany 1313affiliation: Institut de Ciències
del Cosmos, Universitat de Barcelona (IEEC-UB), Carrer Martí i Franquès 1,
E-08028 Barcelona, Spain , Scott F. Anderson1414affiliation: Department of
Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA ,
Brett H. Andrews1515affiliation: PITT PACC, Department of Physics and
Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA , Borja
Anguiano1111affiliation: Department of Astronomy, University of Virginia,
Charlottesville, VA 22904-4325, USA , Erik Aquino-Ortíz1616affiliation:
Instituto de Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264,
04510, Mexico, D.F., México , Alfonso Aragón-Salamanca1717affiliation: School
of Physics and Astronomy, University of Nottingham, University Park,
Nottingham, NG7 2RD, UK , Maria Argudo-Fernández1818affiliation: Instituto de
Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059,
Valparaíso, Chile , Metin Ata1919affiliation: Kavli Institute for the Physics
and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583,
Japan , Marie Aubert2020affiliation: Aix Marseille Université, CNRS/IN2P3,
CPPM, Marseille, France , Vladimir Avila-Reese1616affiliation: Instituto de
Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264, 04510,
Mexico, D.F., México , Carles Badenes1515affiliation: PITT PACC, Department of
Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA ,
Rodolfo H. Barbá2121affiliation: Departamento de Astronomía, Universidad de La
Serena, Av. Juan Cisternas 1200 Norte, La Serena, Chile , Kat
Barger2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA , Jorge K. Barrera-
Ballesteros1616affiliation: Instituto de Astronomía, Universidad Nacional
Autónoma de México, A.P. 70-264, 04510, Mexico, D.F., México , Rachael L.
Beaton2323affiliation: The Observatories of the Carnegie Institution for
Science, 813 Santa Barbara Street, Pasadena, CA 91101, USA , Timothy C.
Beers2424affiliation: Department of Physics and JINA Center for the Evolution
of the Elements, University of Notre Dame, Notre Dame, IN 46556, USA ,
Francesco Belfiore2525affiliation: INAF - Osservatorio Astrofisico di Arcetri,
Largo E. Fermi 5, 50125 Firenze, Italy , Chad F. Bender2626affiliation:
Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson,
AZ 85721-0065, USA , Mariangela Bernardi2727affiliation: Department of Physics
and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA ,
Matthew A. Bershady2828affiliation: Department of Astronomy, University of
Wisconsin-Madison, 475N. Charter St., Madison WI 53703, USA 2929affiliation:
South African Astronomical Observatory, P.O. Box 9, Observatory 7935, Cape
Town, South Africa 3030affiliation: Department of Astronomy, University of
Cape Town, Private Bag X3, Rondebosch 7701, South Africa , Florian
Beutler88affiliation: Institute for Astronomy, University of Edinburgh, Royal
Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK , Christian Moni
Bidin55affiliation: Instituto de Astronomía, Universidad Católica del Norte,
Av. Angamos 0610, Antofagasta, Chile , Jonathan C. Bird3131affiliation:
Department of Physics and Astronomy, Vanderbilt University, VU Station 1807,
Nashville, TN 37235, USA , Dmitry Bizyaev3232affiliation: Apache Point
Observatory, P.O. Box 59, Sunspot, NM 88349, USA 3333affiliation: Sternberg
Astronomical Institute, Moscow State University, Moscow, 119992, Russia ,
Guillermo A. Blanc2323affiliation: The Observatories of the Carnegie
Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101, USA ,
Michael R. Blanton3434affiliation: Center for Cosmology and Particle Physics,
Department of Physics, 726 Broadway, Room 1005, New York University, New York,
NY 10003, USA , Nicholas Fraser Boardman3535affiliation: Department of Physics
and Astronomy, University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112,
USA 3636affiliation: School of Physics and Astronomy, University of St
Andrews, North Haugh, St Andrews KY16 9SS, UK , Adam S. Bolton3737affiliation:
NSF’s National Optical-Infrared Astronomy Research Laboratory, 950 North
Cherry Avenue, Tucson, AZ 85719, USA , Médéric Boquien3838affiliation: Centro
de Astronomía (CITEVA), Universidad de Antofagasta, Avenida Angamos 601,
Antofagasta 1270300, Chile , Jura Borissova3939affiliation: Instituto de
Física y Astronomía, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa
Ancha, Casilla 5030, Chile. 4040affiliation: Millennium Institute of
Astrophysics, MAS, Nuncio Monsenor Sotero Sanz 100, Of. 104, Providencia,
Santiago, Chile , Jo Bovy4141affiliation: David A. Dunlap Department of
Astronomy & Astrophysics, University of Toronto, 50 St. George Street,
Toronto, ON, M5S 3H4, Canada 4242affiliation: Dunlap Institute for Astronomy
and Astrophysics, University of Toronto, 50 St. George Street, Toronto,
Ontario M5S 3H4, Canada , W.N. Brandt4343affiliation: Department of Astronomy
& Astrophysics, Eberly College of Science, The Pennsylvania State University,
525 Davey Laboratory, University Park, PA 16802, USA 4444affiliation:
Institute for Gravitation and the Cosmos, The Pennsylvania State University,
University Park, PA 16802, USA 4545affiliation: Department of Physics, Eberly
College of Science, The Pennsylvania State University, 104 Davey Laboratory,
University Park, PA 16802, USA , Jordan Brown4646affiliation: Department of
Biological and Physical Sciences, South Carolina State University, P.O. Box
7024, Orangeburg, SC 29117, USA , Joel R. Brownstein3535affiliation:
Department of Physics and Astronomy, University of Utah, 115 S. 1400 E., Salt
Lake City, UT 84112, USA , Marcella Brusa4747affiliation: Dipartimento di
Fisica e Astronomia ”Augusto Righi”, Università di Bologna, via Gobetti 93/2,
40129 Bologna, Italy 4848affiliation: INAF - Osservatorio di Astrofisica e
Scienza dello Spazio di Bologna, via Gobetti 93/3, 40129 Bologna, Italy ,
Johannes Buchner4949affiliation: Max-Planck-Institut für extraterrestrische
Physik, Gießenbachstraße 1, 85748 Garching, Germany , Kevin
Bundy5050affiliation: UCO/Lick Observatory, University of California, Santa
Cruz, 1156 High St. Santa Cruz, CA 95064, USA , Joseph N.
Burchett5151affiliation: Department of Astronomy, New Mexico State University,
Las Cruces, NM 88003, USA , Martin Bureau5252affiliation: Sub-department of
Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson
Building, Keble Road, Oxford OX1 3RH, UK , Adam Burgasser5353affiliation:
Center for Astrophysics and Space Science, University of California San Diego,
La Jolla, CA 92093, USA , Tuesday K. Cabang4646affiliation: Department of
Biological and Physical Sciences, South Carolina State University, P.O. Box
7024, Orangeburg, SC 29117, USA , Stephanie Campbell3636affiliation: School of
Physics and Astronomy, University of St Andrews, North Haugh, St Andrews KY16
9SS, UK , Michele Cappellari5252affiliation: Sub-department of Astrophysics,
Department of Physics, University of Oxford, Denys Wilkinson Building, Keble
Road, Oxford OX1 3RH, UK , Joleen K. Carlberg5454affiliation: Space Telescope
Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA , Fábio
Carneiro Wanderley5555affiliation: Observatório Nacional, Rio de Janeiro,
Brasil , Ricardo Carrera5656affiliation: Astronomical Observatory of Padova,
National Institute of Astrophysics, Vicolo Osservatorio 5 - 35122 - Padova,
Italy , Jennifer Cash4646affiliation: Department of Biological and Physical
Sciences, South Carolina State University, P.O. Box 7024, Orangeburg, SC
29117, USA , Yan-Ping Chen5757affiliation: NYU Abu Dhabi, PO Box 129188, Abu
Dhabi, UAE , Wei-Huai Chen11affiliation: Academia Sinica Institute of
Astronomy and Astrophysics, 11F of AS/NTU, Astronomy-Mathematics Building,
No.1, Sec. 4, Roosevelt Rd, Taipei, 10617, Taiwan 5858affiliation: Department
of Physics, National Taiwan University, Taipei 10617, Taiwan , Brian
Cherinka5454affiliation: Space Telescope Science Institute, 3700 San Martin
Drive, Baltimore, MD 21218, USA , Cristina Chiappini1212affiliation: Leibniz-
Institut fur Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam,
Germany , Peter Doohyun Choi5959affiliation: Department of Astronomy and Space
Science, Sejong University, 209, Neungdong-ro, Gwangjin-gu, Seoul, South Korea
, S. Drew Chojnowski5151affiliation: Department of Astronomy, New Mexico State
University, Las Cruces, NM 88003, USA , Haeun Chung2626affiliation: Steward
Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ
85721-0065, USA , Nicolas Clerc6060affiliation: IRAP Institut de Recherche en
Astrophysique et Planétologie, Université de Toulouse, CNRS, UPS, CNES,
Toulouse, France , Roger E. Cohen5454affiliation: Space Telescope Science
Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA , Julia M.
Comerford6161affiliation: Center for Astrophysics and Space Astronomy,
Department of Astrophysical and Planetary Sciences, University of Colorado,
389 UCB, Boulder, CO 80309-0389, USA , Johan Comparat4949affiliation: Max-
Planck-Institut für extraterrestrische Physik, Gießenbachstraße 1, 85748
Garching, Germany , Luiz da Costa6262affiliation: Laboratório
Interinstitucional de e-Astronomia, 77 Rua General José Cristino, Rio de
Janeiro, 20921-400, Brasil , Kevin Covey6363affiliation: Department of Physics
and Astronomy, Western Washington University, 516 High Street, Bellingham, WA
98225, USA , Jeffrey D. Crane2323affiliation: The Observatories of the
Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA
91101, USA , Irene Cruz-Gonzalez1616affiliation: Instituto de Astronomía,
Universidad Nacional Autónoma de México, A.P. 70-264, 04510, Mexico, D.F.,
México , Connor Culhane6363affiliation: Department of Physics and Astronomy,
Western Washington University, 516 High Street, Bellingham, WA 98225, USA ,
Katia Cunha5555affiliation: Observatório Nacional, Rio de Janeiro, Brasil
2626affiliation: Steward Observatory, University of Arizona, 933 North Cherry
Avenue, Tucson, AZ 85721-0065, USA , Y. Sophia Dai (戴昱)6464affiliation:
National Astronomical Observatories of China, Chinese Academy of Sciences, 20A
Datun Road, Chaoyang District, Beijing 100012, China , Guillermo
Damke6565affiliation: Instituto de Investigación Multidisciplinario en Ciencia
y Tecnología, Universidad de La Serena. Avenida Raúl Bitrán S/N, La Serena,
Chile 6666affiliation: AURA Observatory in Chile, Avda. Juan Cisternas 1500,
La Serena, Chile , Jeremy Darling6161affiliation: Center for Astrophysics and
Space Astronomy, Department of Astrophysical and Planetary Sciences,
University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA , James W.
Davidson Jr.1111affiliation: Department of Astronomy, University of Virginia,
Charlottesville, VA 22904-4325, USA , Roger Davies5252affiliation: Sub-
department of Astrophysics, Department of Physics, University of Oxford, Denys
Wilkinson Building, Keble Road, Oxford OX1 3RH, UK , Kyle
Dawson3535affiliation: Department of Physics and Astronomy, University of
Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA , Nathan De
Lee6767affiliation: Department of Physics, Geology, and Engineering Tech,
Northern Kentucky University, Highland Heights, KY 41099, USA , Aleksandar M.
Diamond-Stanic6868affiliation: Department of Physics and Astronomy, Bates
College, 44 Campus Avenue, Lewiston ME 04240, USA , Mariana Cano-
Díaz1616affiliation: Instituto de Astronomía, Universidad Nacional Autónoma de
México, A.P. 70-264, 04510, Mexico, D.F., México , Helena Domínguez
Sánchez6969affiliation: Institute of Space Sciences (ICE, CSIC), Carrer de Can
Magrans S/N, Campus UAB, Barcelona, E-08193, Spain , John
Donor2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA , Chris Duckworth3636affiliation: School
of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews
KY16 9SS, UK , Tom Dwelly4949affiliation: Max-Planck-Institut für
extraterrestrische Physik, Gießenbachstraße 1, 85748 Garching, Germany ,
Daniel J. Eisenstein7070affiliation: Harvard-Smithsonian Center for
Astrophysics, 60 Garden St., MS 20, Cambridge, MA 02138, USA , Yvonne P.
Elsworth7171affiliation: School of Physics and Astronomy, University of
Birmingham, Edgbaston, Birmingham B15 2TT, UK , Eric Emsellem7272affiliation:
European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching,
Germany 7373affiliation: Univ Lyon, Univ Lyon1, ENS de Lyon, CNRS, Centre de
Recherche Astrophysique de Lyon UMR5574, F-69230 Saint-Genis-Laval France ,
Mike Eracleous4343affiliation: Department of Astronomy & Astrophysics, Eberly
College of Science, The Pennsylvania State University, 525 Davey Laboratory,
University Park, PA 16802, USA , Stephanie Escoffier2020affiliation: Aix
Marseille Université, CNRS/IN2P3, CPPM, Marseille, France , Xiaohui
Fan2626affiliation: Steward Observatory, University of Arizona, 933 North
Cherry Avenue, Tucson, AZ 85721-0065, USA , Emily Farr1414affiliation:
Department of Astronomy, University of Washington, Box 351580, Seattle, WA
98195, USA , Shuai Feng7474affiliation: College of Physics, Hebei Normal
University, Shijiazhuang 050024, China , José G. Fernández-
Trincado7575affiliation: Instituto de Astronomía y Ciencias Planetarias,
Universidad de Atacama, Copayapu 485, Copiapó, Chile 55affiliation: Instituto
de Astronomía, Universidad Católica del Norte, Av. Angamos 0610, Antofagasta,
Chile , Diane Feuillet7676affiliation: Max-Planck-Institut für Astronomie,
Königstuhl 17, D-69117 Heidelberg, Germany 7777affiliation: Lund Observatory,
Department of Astronomy and Theoretical Physics, Lund University, Box 43,
SE-22100 Lund, Sweden , Andreas Filipp7878affiliation: Max-Planck-Institut für
Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching, Germany , Sean P
Fillingham1414affiliation: Department of Astronomy, University of Washington,
Box 351580, Seattle, WA 98195, USA , Peter M. Frinchaboy2222affiliation:
Department of Physics & Astronomy, Texas Christian University, Fort Worth, TX
76129, USA , Sebastien Fromenteau7979affiliation: Instituto de Ciencias Fśicas
(ICF), Universidad Nacional Autónoma de México, Av. Universidad s/n, Col.
Chamilpa, Cuernavaca, Morelos, 62210, México , Lluís Galbany6969affiliation:
Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Campus
UAB, Barcelona, E-08193, Spain , Rafael A. García8080affiliation: AIM, CEA,
CNRS, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris Cité,
F-91191 Gif-sur-Yvette, France , D. A. García-Hernández99affiliation:
Instituto de Astrofísica de Canarias (IAC), C/ Via Láctea s/n, E-38205 La
Laguna, Tenerife, Spain 1010affiliation: Universidad de La Laguna (ULL),
Departamento de Astrofísica, E-38206 La Laguna, Tenerife Spain , Junqiang
Ge6464affiliation: National Astronomical Observatories of China, Chinese
Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012, China
, Doug Geisler8181affiliation: Departmento de Astronomía, Universidad de
Concepción, Casilla 160-C, Concepción, Chile 6565affiliation: Instituto de
Investigación Multidisciplinario en Ciencia y Tecnología, Universidad de La
Serena. Avenida Raúl Bitrán S/N, La Serena, Chile 8282affiliation:
Departamento de Física y Astronomía, Facultad de Ciencias, Universidad de La
Serena. Av. Juan Cisternas 1200, La Serena, Chile , Joseph
Gelfand3434affiliation: Center for Cosmology and Particle Physics, Department
of Physics, 726 Broadway, Room 1005, New York University, New York, NY 10003,
USA , Tobias Géron5252affiliation: Sub-department of Astrophysics, Department
of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford
OX1 3RH, UK , Benjamin J. Gibson3535affiliation: Department of Physics and
Astronomy, University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA ,
Julian Goddy8383affiliation: Departments of Physics and Astronomy, Haverford
College, 370 Lancaster Ave, Haverford, PA 19041, USA , Diego Godoy-
Rivera8484affiliation: Department of Astronomy and Center for Cosmology and
AstroParticle Physics, The Ohio State University, 140 W. 18th Ave, Columbus,
OH, 43210, USA , Kathleen Grabowski3232affiliation: Apache Point Observatory,
P.O. Box 59, Sunspot, NM 88349, USA , Paul J. Green7070affiliation: Harvard-
Smithsonian Center for Astrophysics, 60 Garden St., MS 20, Cambridge, MA
02138, USA , Michael Greener1717affiliation: School of Physics and Astronomy,
University of Nottingham, University Park, Nottingham, NG7 2RD, UK , Catherine
J. Grier2626affiliation: Steward Observatory, University of Arizona, 933 North
Cherry Avenue, Tucson, AZ 85721-0065, USA , Emily Griffith8484affiliation:
Department of Astronomy and Center for Cosmology and AstroParticle Physics,
The Ohio State University, 140 W. 18th Ave, Columbus, OH, 43210, USA , Hong
Guo8585affiliation: Shanghai Astronomical Observatory, Chinese Academy of
Sciences, 80 Nandan Road, Shanghai 200030, China , Julien Guy8686affiliation:
Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720,
USA , Massinissa Hadjara8787affiliation: Departamento de Astronomía,
Universidad de Chile, Camino El Observatorio 1515, Las Condes, Chile
8888affiliation: Chinese Academy of Sciences South America Center for
Astronomy, National Astronomical Observatories, CAS, Beijing 100101, China ,
Paul Harding8989affiliation: Department of Astronomy, Case Western Reserve
University, Cleveland, OH 44106, USA , Sten Hasselquist3535affiliation:
Department of Physics and Astronomy, University of Utah, 115 S. 1400 E., Salt
Lake City, UT 84112, USA 9090affiliation: NSF Astronomy and Astrophysics
Postdoctoral Fellow , Christian R. Hayes1414affiliation: Department of
Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA , Fred
Hearty4343affiliation: Department of Astronomy & Astrophysics, Eberly College
of Science, The Pennsylvania State University, 525 Davey Laboratory,
University Park, PA 16802, USA , Jesús Hernández9191affiliation: Universidad
Nacional Autónoma de México, Instituto de Astronomía, AP 106, Ensenada 22800,
BC, Mexico , Lewis Hill9292affiliation: Institute of Cosmology & Gravitation,
University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX, UK ,
David W. Hogg3434affiliation: Center for Cosmology and Particle Physics,
Department of Physics, 726 Broadway, Room 1005, New York University, New York,
NY 10003, USA , Jon A. Holtzman5151affiliation: Department of Astronomy, New
Mexico State University, Las Cruces, NM 88003, USA , Danny
Horta9393affiliation: Astrophysics Research Institute, Liverpool John Moores
University, IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF,
UK , Bau-Ching Hsieh11affiliation: Academia Sinica Institute of Astronomy and
Astrophysics, 11F of AS/NTU, Astronomy-Mathematics Building, No.1, Sec. 4,
Roosevelt Rd, Taipei, 10617, Taiwan , Chin-Hao Hsu11affiliation: Academia
Sinica Institute of Astronomy and Astrophysics, 11F of AS/NTU, Astronomy-
Mathematics Building, No.1, Sec. 4, Roosevelt Rd, Taipei, 10617, Taiwan , Yun-
Hsin Hsu11affiliation: Academia Sinica Institute of Astronomy and
Astrophysics, 11F of AS/NTU, Astronomy-Mathematics Building, No.1, Sec. 4,
Roosevelt Rd, Taipei, 10617, Taiwan 9494affiliation: Institute of Astronomy,
National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu
30013, Taiwan , Daniel Huber9595affiliation: Institute for Astronomy,
University of Hawai’i, 2680 Woodlawn Drive, Honolulu, HI 96822, USA , Marc
Huertas-Company99affiliation: Instituto de Astrofísica de Canarias (IAC), C/
Via Láctea s/n, E-38205 La Laguna, Tenerife, Spain 9696affiliation: LERMA, UMR
8112, PSL University, University of Paris, 75014, Paris, France , Brian
Hutchinson9797affiliation: Computer Science Department, Western Washington
University, 516 High Street, Bellingham, WA 98225, USA 9898affiliation:
Computing & Analytics Division, Pacific Northwest, Richland, WA USA , Ho Seong
Hwang9999affiliation: Korea Astronomy and Space Science Institute, 776
Daedeokdae-ro, Yuseong-gu, Daejeon 305-348, Republic of Korea
100100affiliation: Astronomy Program, Department of Physics and Astronomy,
Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of
Korea , Héctor J. Ibarra-Medel101101affiliation: Department of Astronomy,
University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA , Jacob Ider
Chitham4949affiliation: Max-Planck-Institut für extraterrestrische Physik,
Gießenbachstraße 1, 85748 Garching, Germany , Gabriele S. Ilha6262affiliation:
Laboratório Interinstitucional de e-Astronomia, 77 Rua General José Cristino,
Rio de Janeiro, 20921-400, Brasil 102102affiliation: Departamento de Física,
Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria,
97105-900, Santa Maria, RS, Brazil , Julie Imig5151affiliation: Department of
Astronomy, New Mexico State University, Las Cruces, NM 88003, USA , Will
Jaekle6868affiliation: Department of Physics and Astronomy, Bates College, 44
Campus Avenue, Lewiston ME 04240, USA , Tharindu Jayasinghe8484affiliation:
Department of Astronomy and Center for Cosmology and AstroParticle Physics,
The Ohio State University, 140 W. 18th Ave, Columbus, OH, 43210, USA , Xihan
Ji66affiliation: Department of Physics and Astronomy, University of Kentucky,
505 Rose St., Lexington, KY, 40506-0055, USA , Jennifer A.
Johnson8484affiliation: Department of Astronomy and Center for Cosmology and
AstroParticle Physics, The Ohio State University, 140 W. 18th Ave, Columbus,
OH, 43210, USA , Amy Jones5454affiliation: Space Telescope Science Institute,
3700 San Martin Drive, Baltimore, MD 21218, USA , Henrik
Jönsson103103affiliation: Materials Science and Applied Mathematics, Malmö
University, SE-205 06 Malmö, Sweden , Ivan Katkov5757affiliation: NYU Abu
Dhabi, PO Box 129188, Abu Dhabi, UAE 3333affiliation: Sternberg Astronomical
Institute, Moscow State University, Moscow, 119992, Russia , Dr. Arman
Khalatyan1212affiliation: Leibniz-Institut fur Astrophysik Potsdam (AIP), An
der Sternwarte 16, D-14482 Potsdam, Germany , Karen Kinemuchi3232affiliation:
Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349, USA , Shobhit
Kisku9393affiliation: Astrophysics Research Institute, Liverpool John Moores
University, IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF,
UK , Johan H. Knapen99affiliation: Instituto de Astrofísica de Canarias (IAC),
C/ Via Láctea s/n, E-38205 La Laguna, Tenerife, Spain 1010affiliation:
Universidad de La Laguna (ULL), Departamento de Astrofísica, E-38206 La
Laguna, Tenerife Spain , Jean-Paul Kneib104104affiliation: Institute of
Physics, Laboratory of Astrophysics, Ecole Polytechnique Fédérale de Lausanne
(EPFL), Observatoire de Sauverny, 1290 Versoix, Switzerland , Juna A.
Kollmeier2323affiliation: The Observatories of the Carnegie Institution for
Science, 813 Santa Barbara Street, Pasadena, CA 91101, USA , Miranda
Kong105105affiliation: Bryn Mawr College, 101 North Merion Ave, Bryn Mawr, PA
19010, USA , Marina Kounkel3131affiliation: Department of Physics and
Astronomy, Vanderbilt University, VU Station 1807, Nashville, TN 37235, USA
6363affiliation: Department of Physics and Astronomy, Western Washington
University, 516 High Street, Bellingham, WA 98225, USA , Kathryn
Kreckel106106affiliation: Astronomisches Rechen-Institut, Zentrum für
Astronomie der Universität Heidelberg, Mönchhofstraße 12-14, D-69120
Heidelberg, Germany , Dhanesh Krishnarao2828affiliation: Department of
Astronomy, University of Wisconsin-Madison, 475N. Charter St., Madison WI
53703, USA , Ivan Lacerna7575affiliation: Instituto de Astronomía y Ciencias
Planetarias, Universidad de Atacama, Copayapu 485, Copiapó, Chile
4040affiliation: Millennium Institute of Astrophysics, MAS, Nuncio Monsenor
Sotero Sanz 100, Of. 104, Providencia, Santiago, Chile , Richard R.
Lane107107affiliation: Centro de Investigación en Astronomía, Universidad
Bernardo O’Higgins, Avenida Viel 1497, Santiago, Chile. , Rachel
Langgin105105affiliation: Bryn Mawr College, 101 North Merion Ave, Bryn Mawr,
PA 19010, USA , Ramon Lavender4646affiliation: Department of Biological and
Physical Sciences, South Carolina State University, P.O. Box 7024, Orangeburg,
SC 29117, USA , David R. Law5454affiliation: Space Telescope Science
Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA , Daniel
Lazarz66affiliation: Department of Physics and Astronomy, University of
Kentucky, 505 Rose St., Lexington, KY, 40506-0055, USA , Henry W.
Leung4141affiliation: David A. Dunlap Department of Astronomy & Astrophysics,
University of Toronto, 50 St. George Street, Toronto, ON, M5S 3H4, Canada ,
Ho-Hin Leung3636affiliation: School of Physics and Astronomy, University of St
Andrews, North Haugh, St Andrews KY16 9SS, UK , Hannah M.
Lewis1111affiliation: Department of Astronomy, University of Virginia,
Charlottesville, VA 22904-4325, USA , Cheng Li108108affiliation: Department of
Astronomy, Tsinghua University, Beijing 100084, China , Ran Li6464affiliation:
National Astronomical Observatories of China, Chinese Academy of Sciences, 20A
Datun Road, Chaoyang District, Beijing 100012, China , Jianhui
Lian3535affiliation: Department of Physics and Astronomy, University of Utah,
115 S. 1400 E., Salt Lake City, UT 84112, USA , Fu-Heng
Liang108108affiliation: Department of Astronomy, Tsinghua University, Beijing
100084, China 5252affiliation: Sub-department of Astrophysics, Department of
Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford
OX1 3RH, UK , Lihwai Lin (林俐暉)11affiliation: Academia Sinica Institute of
Astronomy and Astrophysics, 11F of AS/NTU, Astronomy-Mathematics Building,
No.1, Sec. 4, Roosevelt Rd, Taipei, 10617, Taiwan , Yen-Ting Lin11affiliation:
Academia Sinica Institute of Astronomy and Astrophysics, 11F of AS/NTU,
Astronomy-Mathematics Building, No.1, Sec. 4, Roosevelt Rd, Taipei, 10617,
Taiwan , Sicheng Lin3434affiliation: Center for Cosmology and Particle
Physics, Department of Physics, 726 Broadway, Room 1005, New York University,
New York, NY 10003, USA , Chris Lintott5252affiliation: Sub-department of
Astrophysics, Department of Physics, University of Oxford, Denys Wilkinson
Building, Keble Road, Oxford OX1 3RH, UK , Dan Long3232affiliation: Apache
Point Observatory, P.O. Box 59, Sunspot, NM 88349, USA , Penélope Longa-
Peña3838affiliation: Centro de Astronomía (CITEVA), Universidad de
Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile , Carlos López-
Cobá11affiliation: Academia Sinica Institute of Astronomy and Astrophysics,
11F of AS/NTU, Astronomy-Mathematics Building, No.1, Sec. 4, Roosevelt Rd,
Taipei, 10617, Taiwan , Shengdong Lu108108affiliation: Department of
Astronomy, Tsinghua University, Beijing 100084, China , Britt F.
Lundgren109109affiliation: Department of Physics and Astronomy, University of
North Carolina Asheville, One University Heights, Asheville, NC 28804, USA ,
Yuanze Luo110110affiliation: Center for Astrophysical Sciences, Department of
Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street,
Baltimore, MD 21218, USA , J. Ted Mackereth111111affiliation: Canadian
Institute for Theoretical Astrophysics, University of Toronto, 60 St. George
Street, Toronto, ON, M5S 3H8, Canada 4242affiliation: Dunlap Institute for
Astronomy and Astrophysics, University of Toronto, 50 St. George Street,
Toronto, Ontario M5S 3H4, Canada 4141affiliation: David A. Dunlap Department
of Astronomy & Astrophysics, University of Toronto, 50 St. George Street,
Toronto, ON, M5S 3H4, Canada , Axel de la Macorra112112affiliation: Instituto
de Física Universidad Nacional Autónoma de México, Cd. de México 04510, México
, Suvrath Mahadevan4343affiliation: Department of Astronomy & Astrophysics,
Eberly College of Science, The Pennsylvania State University, 525 Davey
Laboratory, University Park, PA 16802, USA , Steven R.
Majewski1111affiliation: Department of Astronomy, University of Virginia,
Charlottesville, VA 22904-4325, USA , Arturo Manchado99affiliation: Instituto
de Astrofísica de Canarias (IAC), C/ Via Láctea s/n, E-38205 La Laguna,
Tenerife, Spain 1010affiliation: Universidad de La Laguna (ULL), Departamento
de Astrofísica, E-38206 La Laguna, Tenerife Spain 113113affiliation: CSIC,
Spain , Travis Mandeville1414affiliation: Department of Astronomy, University
of Washington, Box 351580, Seattle, WA 98195, USA , Claudia
Maraston9292affiliation: Institute of Cosmology & Gravitation, University of
Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX, UK , Berta Margalef-
Bentabol2727affiliation: Department of Physics and Astronomy, University of
Pennsylvania, Philadelphia, PA 19104, USA , Thomas Masseron99affiliation:
Instituto de Astrofísica de Canarias (IAC), C/ Via Láctea s/n, E-38205 La
Laguna, Tenerife, Spain 1010affiliation: Universidad de La Laguna (ULL),
Departamento de Astrofísica, E-38206 La Laguna, Tenerife Spain , Karen L.
Masters8383affiliation: Departments of Physics and Astronomy, Haverford
College, 370 Lancaster Ave, Haverford, PA 19041, USA 114114affiliation: SDSS-
IV Spokesperson , Savita Mathur99affiliation: Instituto de Astrofísica de
Canarias (IAC), C/ Via Láctea s/n, E-38205 La Laguna, Tenerife, Spain
1010affiliation: Universidad de La Laguna (ULL), Departamento de Astrofísica,
E-38206 La Laguna, Tenerife Spain , Richard M. McDermid115115affiliation:
Department of Physics and Astronomy, Macquarie University, Sydney NSW 2109,
Australia 116116affiliation: ARC Centre of Excellence for All Sky Astrophysics
in 3 Dimensions (ASTRO 3D), Australia , Myles Mckay1414affiliation: Department
of Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA ,
Andrea Merloni4949affiliation: Max-Planck-Institut für extraterrestrische
Physik, Gießenbachstraße 1, 85748 Garching, Germany , Michael
Merrifield1717affiliation: School of Physics and Astronomy, University of
Nottingham, University Park, Nottingham, NG7 2RD, UK , Szabolcs
Meszaros117117affiliation: ELTE Eötvös Loránd University, Gothard
Astrophysical Observatory, 9700 Szombathely, Szent Imre H. st. 112, Hungary
118118affiliation: MTA-ELTE Lendület Milky Way Research Group, Hungary
119119affiliation: MTA-ELTE Exoplanet Research Group, Hungary , Andrea
Miglio4747affiliation: Dipartimento di Fisica e Astronomia ”Augusto Righi”,
Università di Bologna, via Gobetti 93/2, 40129 Bologna, Italy , Francesco Di
Mille120120affiliation: Las Campanas Observatory, Colina El Pino Casilla 601
La Serena, Chile , Dante Minniti121121affiliation: Departamento de Ciencias
Fısicas, Universidad Andres Bello, Av. Republica 220, Santiago, Chile
153153affiliation: Vatican Observatory, V00120 Vatican City State, Italy ,
Rebecca Minsley6868affiliation: Department of Physics and Astronomy, Bates
College, 44 Campus Avenue, Lewiston ME 04240, USA , Antonela
Monachesi6565affiliation: Instituto de Investigación Multidisciplinario en
Ciencia y Tecnología, Universidad de La Serena. Avenida Raúl Bitrán S/N, La
Serena, Chile , Jeongin Moon5959affiliation: Department of Astronomy and Space
Science, Sejong University, 209, Neungdong-ro, Gwangjin-gu, Seoul, South Korea
, Benoit Mosser122122affiliation: LESIA, Observatoire de Paris, Université
PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen,
92195 Meudon, France , John Mulchaey2323affiliation: The Observatories of the
Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA
91101, USA , Demitri Muna8484affiliation: Department of Astronomy and Center
for Cosmology and AstroParticle Physics, The Ohio State University, 140 W.
18th Ave, Columbus, OH, 43210, USA , Ricardo R. Muñoz8787affiliation:
Departamento de Astronomía, Universidad de Chile, Camino El Observatorio 1515,
Las Condes, Chile , Adam D. Myers123123affiliation: Department of Physics and
Astronomy, University of Wyoming, Laramie, WY 82071, USA , Natalie
Myers2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA , Seshadri Nadathur124124affiliation:
Department of Physics & Astronomy, University College London, Gower Street,
London, WC1E 6BT, UK , Preethi Nair125125affiliation: Department of Physics
and Astronomy, University of Alabama, Tuscaloosa, AL 35487, USA , Kirpal
Nandra4949affiliation: Max-Planck-Institut für extraterrestrische Physik,
Gießenbachstraße 1, 85748 Garching, Germany , Justus Neumann9292affiliation:
Institute of Cosmology & Gravitation, University of Portsmouth, Dennis Sciama
Building, Portsmouth, PO1 3FX, UK , Jeffrey A. Newman1515affiliation: PITT
PACC, Department of Physics and Astronomy, University of Pittsburgh,
Pittsburgh, PA 15260, USA , David L. Nidever126126affiliation: Department of
Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840,
USA , Farnik Nikakhtar2727affiliation: Department of Physics and Astronomy,
University of Pennsylvania, Philadelphia, PA 19104, USA , Christian
Nitschelm3838affiliation: Centro de Astronomía (CITEVA), Universidad de
Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile , Julia E.
O’Connell2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA 8181affiliation: Departmento de
Astronomía, Universidad de Concepción, Casilla 160-C, Concepción, Chile , Luis
Garma-Oehmichen1616affiliation: Instituto de Astronomía, Universidad Nacional
Autónoma de México, A.P. 70-264, 04510, Mexico, D.F., México , Gabriel Luan
Souza de Oliveira102102affiliation: Departamento de Física, Centro de Ciências
Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900, Santa
Maria, RS, Brazil 6262affiliation: Laboratório Interinstitucional de
e-Astronomia, 77 Rua General José Cristino, Rio de Janeiro, 20921-400, Brasil
, Richard Olney6363affiliation: Department of Physics and Astronomy, Western
Washington University, 516 High Street, Bellingham, WA 98225, USA , Daniel
Oravetz3232affiliation: Apache Point Observatory, P.O. Box 59, Sunspot, NM
88349, USA , Mario Ortigoza-Urdaneta7575affiliation: Instituto de Astronomía y
Ciencias Planetarias, Universidad de Atacama, Copayapu 485, Copiapó, Chile ,
Yeisson Osorio99affiliation: Instituto de Astrofísica de Canarias (IAC), C/
Via Láctea s/n, E-38205 La Laguna, Tenerife, Spain , Justin
Otter110110affiliation: Center for Astrophysical Sciences, Department of
Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street,
Baltimore, MD 21218, USA , Zachary J. Pace2828affiliation: Department of
Astronomy, University of Wisconsin-Madison, 475N. Charter St., Madison WI
53703, USA , Nelson Padilla127127affiliation: Instituto de Astrofísica,
Pontificia Universidad Católica de Chile, Av. Vicuna Mackenna 4860, 782-0436
Macul, Santiago, Chile , Kaike Pan3232affiliation: Apache Point Observatory,
P.O. Box 59, Sunspot, NM 88349, USA , Hsi-An Pan7676affiliation: Max-Planck-
Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany , Taniya
Parikh4949affiliation: Max-Planck-Institut für extraterrestrische Physik,
Gießenbachstraße 1, 85748 Garching, Germany , James Parker3232affiliation:
Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349, USA , Sebastien
Peirani128128affiliation: Institut d’Astrophysique de Paris, UMR 7095, SU-
CNRS, 98bis bd Arago, 75014 Paris, France , Karla Peña Ramírez3838affiliation:
Centro de Astronomía (CITEVA), Universidad de Antofagasta, Avenida Angamos
601, Antofagasta 1270300, Chile , Samantha Penny9292affiliation: Institute of
Cosmology & Gravitation, University of Portsmouth, Dennis Sciama Building,
Portsmouth, PO1 3FX, UK , Will J. Percival129129affiliation: Waterloo Centre
for Astrophysics, University of Waterloo, Waterloo, ON N2L 3G1, Canada
130130affiliation: Department of Physics and Astronomy, University of
Waterloo, Waterloo, ON N2L 3G1, Canada 131131affiliation: Perimeter Institute
for Theoretical Physics, Waterloo, ON N2L 2Y5, Canada , Ismael Perez-
Fournon99affiliation: Instituto de Astrofísica de Canarias (IAC), C/ Via
Láctea s/n, E-38205 La Laguna, Tenerife, Spain 1010affiliation: Universidad de
La Laguna (ULL), Departamento de Astrofísica, E-38206 La Laguna, Tenerife
Spain , Marc Pinsonneault8484affiliation: Department of Astronomy and Center
for Cosmology and AstroParticle Physics, The Ohio State University, 140 W.
18th Ave, Columbus, OH, 43210, USA , Frédérick Poidevin99affiliation:
Instituto de Astrofísica de Canarias (IAC), C/ Via Láctea s/n, E-38205 La
Laguna, Tenerife, Spain 1010affiliation: Universidad de La Laguna (ULL),
Departamento de Astrofísica, E-38206 La Laguna, Tenerife Spain , Vijith Jacob
Poovelil3535affiliation: Department of Physics and Astronomy, University of
Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA , Adrian M. Price-
Whelan132132affiliation: Center for Computational Astrophysics, Flatiron
Institute, 162 Fifth Avenue, New York, NY, 10010 , Anna Bárbara de Andrade
Queiroz1212affiliation: Leibniz-Institut fur Astrophysik Potsdam (AIP), An der
Sternwarte 16, D-14482 Potsdam, Germany , M. Jordan Raddick110110affiliation:
Center for Astrophysical Sciences, Department of Physics and Astronomy, Johns
Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA , Amy
Ray2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA , Sandro Barboza
Rembold102102affiliation: Departamento de Física, Centro de Ciências Naturais
e Exatas, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS,
Brazil 6262affiliation: Laboratório Interinstitucional de e-Astronomia, 77 Rua
General José Cristino, Rio de Janeiro, 20921-400, Brasil , Nicole
Riddle2222affiliation: Department of Physics & Astronomy, Texas Christian
University, Fort Worth, TX 76129, USA , Rogemar A. Riffel6262affiliation:
Laboratório Interinstitucional de e-Astronomia, 77 Rua General José Cristino,
Rio de Janeiro, 20921-400, Brasil 102102affiliation: Departamento de Física,
Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria,
97105-900, Santa Maria, RS, Brazil , Rogério Riffel133133affiliation:
Departamento de Astronomia, Instituto de Física, Universidade Federal do Rio
Grande do Sul. Av. Bento Goncalves 9500, 91501-970, Porto Alegre, RS, Brazil
6262affiliation: Laboratório Interinstitucional de e-Astronomia, 77 Rua
General José Cristino, Rio de Janeiro, 20921-400, Brasil , Hans-Walter
Rix7676affiliation: Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117
Heidelberg, Germany , Annie C. Robin134134affiliation: Institut UTINAM, CNRS,
OSU THETA Franche-Comté Bourgogne, Univ. Bourgogne Franche-Comté, 25000
Besançon, France , Aldo Rodríguez-Puebla1616affiliation: Instituto de
Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264, 04510,
Mexico, D.F., México , Alexandre Roman-Lopes2121affiliation: Departamento de
Astronomía, Universidad de La Serena, Av. Juan Cisternas 1200 Norte, La
Serena, Chile , Carlos Román-Zúñiga9191affiliation: Universidad Nacional
Autónoma de México, Instituto de Astronomía, AP 106, Ensenada 22800, BC,
Mexico , Benjamin Rose2424affiliation: Department of Physics and JINA Center
for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN
46556, USA , Ashley J. Ross135135affiliation: Department of Physics and Center
for Cosmology and AstroParticle Physics, The Ohio State University, Columbus,
OH 43210, USA , Graziano Rossi5959affiliation: Department of Astronomy and
Space Science, Sejong University, 209, Neungdong-ro, Gwangjin-gu, Seoul, South
Korea , Kate H. R. Rubin136136affiliation: Department of Astronomy, San Diego
State University, San Diego, CA 92182, USA 5353affiliation: Center for
Astrophysics and Space Science, University of California San Diego, La Jolla,
CA 92093, USA , Mara Salvato4949affiliation: Max-Planck-Institut für
extraterrestrische Physik, Gießenbachstraße 1, 85748 Garching, Germany ,
Sebástian F. Sánchez1616affiliation: Instituto de Astronomía, Universidad
Nacional Autónoma de México, A.P. 70-264, 04510, Mexico, D.F., México , José
R. Sánchez-Gallego1414affiliation: Department of Astronomy, University of
Washington, Box 351580, Seattle, WA 98195, USA , Robyn
Sanderson2727affiliation: Department of Physics and Astronomy, University of
Pennsylvania, Philadelphia, PA 19104, USA 132132affiliation: Center for
Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York,
NY, 10010 , Felipe Antonio Santana Rojas8787affiliation: Departamento de
Astronomía, Universidad de Chile, Camino El Observatorio 1515, Las Condes,
Chile , Edgar Sarceno6868affiliation: Department of Physics and Astronomy,
Bates College, 44 Campus Avenue, Lewiston ME 04240, USA , Regina
Sarmiento99affiliation: Instituto de Astrofísica de Canarias (IAC), C/ Via
Láctea s/n, E-38205 La Laguna, Tenerife, Spain 1010affiliation: Universidad de
La Laguna (ULL), Departamento de Astrofísica, E-38206 La Laguna, Tenerife
Spain , Conor Sayres1414affiliation: Department of Astronomy, University of
Washington, Box 351580, Seattle, WA 98195, USA , Elizaveta
Sazonova110110affiliation: Center for Astrophysical Sciences, Department of
Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street,
Baltimore, MD 21218, USA , Adam L. Schaefer7878affiliation: Max-Planck-
Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching, Germany
, David J Schlegel8686affiliation: Lawrence Berkeley National Laboratory, 1
Cyclotron Road, Berkeley, CA 94720, USA , Donald P. Schneider4343affiliation:
Department of Astronomy & Astrophysics, Eberly College of Science, The
Pennsylvania State University, 525 Davey Laboratory, University Park, PA
16802, USA 4444affiliation: Institute for Gravitation and the Cosmos, The
Pennsylvania State University, University Park, PA 16802, USA , Ricardo
Schiavon9393affiliation: Astrophysics Research Institute, Liverpool John
Moores University, IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool
L3 5RF, UK , Mathias Schultheis137137affiliation: Observatoire de la Côte
d’Azur, Laboratoire Lagrange, 06304 Nice Cedex 4, France , Axel
Schwope1212affiliation: Leibniz-Institut fur Astrophysik Potsdam (AIP), An der
Sternwarte 16, D-14482 Potsdam, Germany , Aldo Serenelli6969affiliation:
Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Campus
UAB, Barcelona, E-08193, Spain 138138affiliation: Institut d’Estudis Espacials
de Catalunya, C. Gran Capita 2-4, Barcelona, Spain , Javier
Serna1616affiliation: Instituto de Astronomía, Universidad Nacional Autónoma
de México, A.P. 70-264, 04510, Mexico, D.F., México , Zhengyi
Shao8585affiliation: Shanghai Astronomical Observatory, Chinese Academy of
Sciences, 80 Nandan Road, Shanghai 200030, China , Griffin
Shapiro139139affiliation: Middlebury College, Middlebury, Vermont 05753, USA ,
Anubhav Sharma8383affiliation: Departments of Physics and Astronomy, Haverford
College, 370 Lancaster Ave, Haverford, PA 19041, USA , Yue
Shen101101affiliation: Department of Astronomy, University of Illinois at
Urbana-Champaign, Urbana, IL 61801, USA , Matthew Shetrone5050affiliation:
UCO/Lick Observatory, University of California, Santa Cruz, 1156 High St.
Santa Cruz, CA 95064, USA , Yiping Shu7878affiliation: Max-Planck-Institut für
Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching, Germany , Joshua D.
Simon2323affiliation: The Observatories of the Carnegie Institution for
Science, 813 Santa Barbara Street, Pasadena, CA 91101, USA , M. F.
Skrutskie1111affiliation: Department of Astronomy, University of Virginia,
Charlottesville, VA 22904-4325, USA , Rebecca Smethurst5252affiliation: Sub-
department of Astrophysics, Department of Physics, University of Oxford, Denys
Wilkinson Building, Keble Road, Oxford OX1 3RH, UK , Verne
Smith3737affiliation: NSF’s National Optical-Infrared Astronomy Research
Laboratory, 950 North Cherry Avenue, Tucson, AZ 85719, USA , Jennifer
Sobeck1414affiliation: Department of Astronomy, University of Washington, Box
351580, Seattle, WA 98195, USA , Taylor Spoo2222affiliation: Department of
Physics & Astronomy, Texas Christian University, Fort Worth, TX 76129, USA ,
Dani Sprague9797affiliation: Computer Science Department, Western Washington
University, 516 High Street, Bellingham, WA 98225, USA , David V.
Stark8383affiliation: Departments of Physics and Astronomy, Haverford College,
370 Lancaster Ave, Haverford, PA 19041, USA , Keivan G.
Stassun3131affiliation: Department of Physics and Astronomy, Vanderbilt
University, VU Station 1807, Nashville, TN 37235, USA , Matthias
Steinmetz1212affiliation: Leibniz-Institut fur Astrophysik Potsdam (AIP), An
der Sternwarte 16, D-14482 Potsdam, Germany , Dennis Stello140140affiliation:
Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW
2006, Australia 141141affiliation: School of Physics, UNSW Sydney, NSW 2052,
Australia , Alexander Stone-Martinez5151affiliation: Department of Astronomy,
New Mexico State University, Las Cruces, NM 88003, USA , Thaisa Storchi-
Bergmann133133affiliation: Departamento de Astronomia, Instituto de Física,
Universidade Federal do Rio Grande do Sul. Av. Bento Goncalves 9500,
91501-970, Porto Alegre, RS, Brazil 6262affiliation: Laboratório
Interinstitucional de e-Astronomia, 77 Rua General José Cristino, Rio de
Janeiro, 20921-400, Brasil , Guy S. Stringfellow6161affiliation: Center for
Astrophysics and Space Astronomy, Department of Astrophysical and Planetary
Sciences, University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA ,
Amelia Stutz8181affiliation: Departmento de Astronomía, Universidad de
Concepción, Casilla 160-C, Concepción, Chile , Yung-Chau Su11affiliation:
Academia Sinica Institute of Astronomy and Astrophysics, 11F of AS/NTU,
Astronomy-Mathematics Building, No.1, Sec. 4, Roosevelt Rd, Taipei, 10617,
Taiwan 5858affiliation: Department of Physics, National Taiwan University,
Taipei 10617, Taiwan , Manuchehr Taghizadeh-Popp110110affiliation: Center for
Astrophysical Sciences, Department of Physics and Astronomy, Johns Hopkins
University, 3400 North Charles Street, Baltimore, MD 21218, USA , Michael S.
Talbot3535affiliation: Department of Physics and Astronomy, University of
Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA , Jamie
Tayar9595affiliation: Institute for Astronomy, University of Hawai’i, 2680
Woodlawn Drive, Honolulu, HI 96822, USA 142142affiliation: Hubble Fellow ,
Eduardo Telles5555affiliation: Observatório Nacional, Rio de Janeiro, Brasil ,
Johanna Teske143143affiliation: Carnegie Institution for Science, Earth and
Planets Laboratory, 5241 Broad Branch Road NW, Washington, DC 20015, USA , Ani
Thakar110110affiliation: Center for Astrophysical Sciences, Department of
Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street,
Baltimore, MD 21218, USA , Christopher Theissen5353affiliation: Center for
Astrophysics and Space Science, University of California San Diego, La Jolla,
CA 92093, USA , Daniel Thomas9292affiliation: Institute of Cosmology &
Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1
3FX, UK , Andrew Tkachenko33affiliation: Institute of Astronomy, KU Leuven,
Celestijnenlaan 200D, B-3001 Leuven, Belgium , Rita Tojeiro3636affiliation:
School of Physics and Astronomy, University of St Andrews, North Haugh, St
Andrews KY16 9SS, UK , Hector Hernandez Toledo1616affiliation: Instituto de
Astronomía, Universidad Nacional Autónoma de México, A.P. 70-264, 04510,
Mexico, D.F., México , Nicholas W. Troup144144affiliation: Department of
Physics, Salisbury University, 1101 Camden Ave., Salisbury, MD 21804, USA ,
Jonathan R. Trump145145affiliation: Department of Physics, University of
Connecticut, 2152 Hillside Road, Unit 3046, Storrs, CT 06269, USA , James
Trussler146146affiliation: Cavendish Laboratory, University of Cambridge, 19
J. J. Thomson Avenue, Cambridge CB3 0HE, UK 147147affiliation: Kavli Institute
for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA,
United Kingdom , Jacqueline Turner8383affiliation: Departments of Physics and
Astronomy, Haverford College, 370 Lancaster Ave, Haverford, PA 19041, USA ,
Sarah Tuttle1414affiliation: Department of Astronomy, University of
Washington, Box 351580, Seattle, WA 98195, USA , Eduardo Unda-
Sanzana3838affiliation: Centro de Astronomía (CITEVA), Universidad de
Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile , José Antonio
Vázquez-Mata1616affiliation: Instituto de Astronomía, Universidad Nacional
Autónoma de México, A.P. 70-264, 04510, Mexico, D.F., México
148148affiliation: Departamento de Física, Facultad de Ciencias, Universidad
Nacional Autónoma de México, Ciudad Universitaria, CDMX, 04510, México ,
Marica Valentini1212affiliation: Leibniz-Institut fur Astrophysik Potsdam
(AIP), An der Sternwarte 16, D-14482 Potsdam, Germany , Octavio
Valenzuela1616affiliation: Instituto de Astronomía, Universidad Nacional
Autónoma de México, A.P. 70-264, 04510, Mexico, D.F., México , Jaime Vargas-
González149149affiliation: Centre for Astrophysics Research, School of
Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane,
Hatfield AL10 9AB, UK , Mariana Vargas-Magaña112112affiliation: Instituto de
Física Universidad Nacional Autónoma de México, Cd. de México 04510, México ,
Pablo Vera Alfaro2121affiliation: Departamento de Astronomía, Universidad de
La Serena, Av. Juan Cisternas 1200 Norte, La Serena, Chile , Sandro
Villanova8181affiliation: Departmento de Astronomía, Universidad de
Concepción, Casilla 160-C, Concepción, Chile , Fiorenzo
Vincenzo8484affiliation: Department of Astronomy and Center for Cosmology and
AstroParticle Physics, The Ohio State University, 140 W. 18th Ave, Columbus,
OH, 43210, USA , David Wake109109affiliation: Department of Physics and
Astronomy, University of North Carolina Asheville, One University Heights,
Asheville, NC 28804, USA , Jack T. Warfield1111affiliation: Department of
Astronomy, University of Virginia, Charlottesville, VA 22904-4325, USA ,
Jessica Diane Washington150150affiliation: Wellesley College Address: 106
Central St, Wellesley, MA 02481, USA , Benjamin Alan Weaver3737affiliation:
NSF’s National Optical-Infrared Astronomy Research Laboratory, 950 North
Cherry Avenue, Tucson, AZ 85719, USA , Anne-Marie Weijmans3636affiliation:
School of Physics and Astronomy, University of St Andrews, North Haugh, St
Andrews KY16 9SS, UK , David H. Weinberg8484affiliation: Department of
Astronomy and Center for Cosmology and AstroParticle Physics, The Ohio State
University, 140 W. 18th Ave, Columbus, OH, 43210, USA , Achim
Weiss7878affiliation: Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-
Str. 1, D-85748 Garching, Germany , Kyle B. Westfall5050affiliation: UCO/Lick
Observatory, University of California, Santa Cruz, 1156 High St. Santa Cruz,
CA 95064, USA , Vivienne Wild3636affiliation: School of Physics and Astronomy,
University of St Andrews, North Haugh, St Andrews KY16 9SS, UK , Matthew C.
Wilde1414affiliation: Department of Astronomy, University of Washington, Box
351580, Seattle, WA 98195, USA , John C. Wilson1111affiliation: Department of
Astronomy, University of Virginia, Charlottesville, VA 22904-4325, USA ,
Robert F. Wilson1111affiliation: Department of Astronomy, University of
Virginia, Charlottesville, VA 22904-4325, USA , Mikayla Wilson2222affiliation:
Department of Physics & Astronomy, Texas Christian University, Fort Worth, TX
76129, USA , Julien Wolf4949affiliation: Max-Planck-Institut für
extraterrestrische Physik, Gießenbachstraße 1, 85748 Garching, Germany
151151affiliation: Exzellenzcluster ORIGINS, Boltzmannstr. 2, D-85748
Garching, Germany , W. M. Wood-Vasey1515affiliation: PITT PACC, Department of
Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260, USA ,
Renbin Yan (严人斌)152152affiliation: Department of Physics, The Chinese
University of Hong Kong, Shatin, N.T., Hong Kong SAR, China 66affiliation:
Department of Physics and Astronomy, University of Kentucky, 505 Rose St.,
Lexington, KY, 40506-0055, USA , Olga Zamora99affiliation: Instituto de
Astrofísica de Canarias (IAC), C/ Via Láctea s/n, E-38205 La Laguna, Tenerife,
Spain , Gail Zasowski3535affiliation: Department of Physics and Astronomy,
University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA , Kai
Zhang8686affiliation: Lawrence Berkeley National Laboratory, 1 Cyclotron Road,
Berkeley, CA 94720, USA , Cheng Zhao104104affiliation: Institute of Physics,
Laboratory of Astrophysics, Ecole Polytechnique Fédérale de Lausanne (EPFL),
Observatoire de Sauverny, 1290 Versoix, Switzerland , Zheng
Zheng3535affiliation: Department of Physics and Astronomy, University of Utah,
115 S. 1400 E., Salt Lake City, UT 84112, USA , Zheng Zheng6464affiliation:
National Astronomical Observatories of China, Chinese Academy of Sciences, 20A
Datun Road, Chaoyang District, Beijing 100012, China , Kai Zhu6464affiliation:
National Astronomical Observatories of China, Chinese Academy of Sciences, 20A
Datun Road, Chaoyang District, Beijing 100012, China

###### Abstract

This paper documents the seventeenth data release (DR17) from the Sloan
Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-
IV). DR17 contains the complete release of the Mapping Nearby Galaxies at
Apache Point Observatory (MaNGA) survey, which reached its goal of surveying
over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library
(MaStar) accompanies this data, providing observations of almost 30,000 stars
through the MaNGA instrument during bright time. DR17 also contains the
complete release of the Apache Point Observatory Galactic Evolution Experiment
2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000
stars. The main sample from the Extended Baryon Oscillation Spectroscopic
Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey
(TDSS) data were fully released in DR16. New single-fiber optical spectroscopy
released in DR17 is from the SPectroscipic IDentification of ERosita Survey
(SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data
sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper
concludes the release of SDSS-IV survey data. SDSS continues into its fifth
phase with observations already underway for the Milky Way Mapper (MWM), Local
Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys.

###### Subject headings:

Atlases — Catalogs — Surveys

##  1\. Introduction

The Sloan Digital Sky Surveys (SDSS) have been almost continuously observing
the skies for over 20 years, since the project began with a first phase in
1998 (SDSS-I; York et al. 2000). SDSS has now completed four phases of
operations (with a fifth ongoing; see §8). Since 2017, SDSS has had a dual
hemisphere view of the sky, observing from both Las Campanas Observatory
(LCO), using the du Pont Telescope and the Sloan Foundation 2.5-m Telescope,
(Gunn et al., 2006) at Apache Point Observatory (APO). This paper describes
data taken during the fourth phase of SDSS (SDSS-IV; Blanton et al. 2017),
which consisted of three main surveys; the Extended Baryon Oscillation
Spectroscopic Survey (eBOSS; Dawson et al. 2016), Mapping Nearby Galaxies at
APO (MaNGA; Bundy et al. 2015), and the APO Galactic Evolution Experiment 2
(APOGEE-2; Majewski et al. 2017). Within eBOSS, SDSS-IV also conducted two
smaller programs: the SPectroscopic IDentification of ERosita Sources
(SPIDERS; Clerc et al. 2016; Dwelly et al. 2017) and the Time Domain
Spectroscopic Survey (TDSS; Morganson et al. 2015), and continued the SDSS
Reverberation Mapping (SDSS-RM) program to measure black hole masses out to
redshifts $z\sim 1$–2 using single fiber spectra. Finally, the use of dual
observing modes with the MaNGA and APOGEE instruments (Drory et al. 2015;
Wilson et al. 2019) facilitated the development of the MaNGA Stellar Library
(MaStar; Yan et al. 2019), which observed stars using the MaNGA fiber bundles
during APOGEE-led bright time observing.

This suite of SDSS-IV programs was developed to map the Universe on a range of
scales, from stars in the Milky Way and nearby satellites in APOGEE-2, to
nearby galaxies in MaNGA, and out to cosmological scales with eBOSS. SPIDERS
provided follow-up observations of X-ray emitting sources, especially from
eROSITA (Merloni et al. 2012; Predehl et al. 2014), and TDSS and SDSS-RM
provided a spectroscopic view of the variable sky.

The final year’s schedule for SDSS-IV was substantially altered due to the
COVID-19 pandemic. Originally, the SDSS-IV observations were scheduled to end
at APO on the night of June 30, 2020 and at LCO on the night of September 8,
2020. Closures in response to COVID-19 altered this plan. APO closed on the
morning of March 24, 2020 and the 2.5-m Sloan Foundation Telescope reopened
for science observations the night of June 2, 2020. The summer shutdown
ordinarily scheduled in July and August was delayed and instead SDSS-IV
observations continued through the morning of August 24, 2020. LCO closed on
the morning of March 17, 2020 and the du Pont Telescope reopened for science
observations the night of October 20, 2020. The du Pont Telescope was used
almost continuously for SDSS-IV through the morning of January 21, 2021. These
changes led to different sky coverages than were originally planned for SDSS-
IV but still allowed it to achieve or exceed all of its original goals.

This paper documents the seventeenth data release (DR17) from SDSS overall,
and is the fifth and final annual release from SDSS-IV (following DR13:
Albareti et al. 2017; DR14: Abolfathi et al. 2018, DR15: Aguado et al. 2019
and DR16: Ahumada et al. 2020). With this release SDSS-IV has completed the
goals set out in Blanton et al. (2017).

A complete overview of the scope of DR17 is provided in §2, and information on
how to access the data can be found in §3. We have separate sections on MaNGA
(§5), MaStar (§6) and APOGEE-2 (§4), and while there is no new main eBOSS
survey or TDSS data in this release, we document releases from SPIDERS and the
eBOSS-RM program as well as eBOSS related value added cataloges (VACs) in §7.
We conclude with a summary of the current status of SDSS-V now in active
operations along with describing plans for future data releases (§8).

##  2\. Scope of DR17

SDSS data releases have always been cumulative, and DR17 follows that
tradition, meaning that the most up-to-date reduction of data in all previous
data releases are included in DR17. The exact data products and catalogs of
previous releases also remain accessible on our servers. However, we
emphatically advise users to access any SDSS data from the most recent SDSS
data release, because data may have been reprocessed using updated data
reduction pipelines, and catalogs may have been updated with new entries
and/or improved analysis methods. Changes between the processing methods used
in DR17 compared to previous data releases are documented on the DR17 version
of the SDSS website https://www.sdss.org/dr17 as well as in this article.

This data release itself includes over 46 million new files totalling over 222
TB. Although many of these files replace previous versions, the total volume
of all SDSS files including all previous versions now exceeds 623 TB on the
Science Archive Server (SAS). The growth of the volume of data on the SAS
since DR8 (which was the first data release of SDSS-III) is shown in Figure 1.

Figure 1.— The growth in data volume hosted by the SDSS Science Archive Server (SAS) since DR8. For a more detailed break down of data volume see https://sdss.org/dr17/data_access/volume Table 1SDSS-IV spectroscopic data in all releases (DR13–DR17)  Target Category | DR13 | DR14 | DR15 | DR16 | DR17
---|---|---|---|---|---
APOGEE-2 |  |
Main Red Star Sample | 109376 | 184148 | 184148 | 281575 | 372458
AllStar Entries | 164562 | 277371 | 277371 | 473307 | 733901
APOGEE-2S Main Red Star Sample | - | - | - | 56480 | 96547
APOGEE-2S AllStar Entries | - | - | - | 102200 | 204193
APOGEE-2S Contributed AllStar Entries | - | - | - | 37409 | 92152
NMSU 1-meter AllStar Entries | 894 | 1018 | 1018 | 1071 | 1175
Telluric AllStar Entries | 17293 | 27127 | 27127 | 34016 | 45803
MaNGA |  |
All Cubes | 1390 | 2812 | 4824 | 4824 | 11273
Main galaxy sample: |  |
PRIMARY_v1_2 | 600 | 1278 | 2126 | 2126 | 4621
SECONDARY_v1_2 | 473 | 947 | 1665 | 1665 | 3724
COLOR-ENHANCED_v1_2 | 216 | 447 | 710 | 710 | 1514
Other targets33Data cubes not in any of the 3 main galaxy samples, including both ancillary program targets and non-galaxy data cubes. | 31 | 121 | 324 | 324 | 1420
MaStar (MaNGA Stellar Library) |  |
All Cubes | 0 | 0 | 3321 | 3321 | 24130
eBOSS |  |
LRG samples | 32968 | 138777 | 138777 | 298762 | 298762
ELG samples | 14459 | 35094 | 35094 | 269889 | 269889
Main QSO sample | 33928 | 188277 | 188277 | 434820 | 434820
Variability selected QSOs | 22756 | 87270 | 87270 | 185816 | 186625
Other QSO samples | 24840 | 43502 | 43502 | 70785 | 73574
TDSS targets | 17927 | 57675 | 57675 | 131552 | 131552
SPIDERS targets | 3133 | 16394 | 16394 | 36300 | 41969
Reverberation Mapping | 84911The number of RM targets remains the same, but the number of visits increases. | 84911The number of RM targets remains the same, but the number of visits increases. | 84911The number of RM targets remains the same, but the number of visits increases. | 84911The number of RM targets remains the same, but the number of visits increases. | 84911The number of RM targets remains the same, but the number of visits increases.
Standard Stars/White Dwarfs | 53584 | 63880 | 63880 | 84605 | 85105
|  |  |  |  |

Table 1 shows the growth of SDSS-IV data separated by survey and target types
across our five annual data releases. These numbers are a mixture of counts of
unique spectra and unique objects, and while correct to the best of our
ability, can be subject to change based on which quality control flags are
implemented. We also summarize these information below:

  1. 1.

APOGEE-2 is including 879,437 new infrared spectra.111The number of spectra
are tallied as the number of new entries in the AllVisit file. Table 1 conveys
the numbers of unique targets that come from the AllStar file. These data come
from observations taken from MJD 58302 to MJD 59160 (i.e., from July 2, 2018
to November 07, 2020) for APOGEE-2 North (APOGEE-2N) at APO and from MJD 58358
to MJD 59234 (August 29, 2018 to January 20, 2021) for APOGEE-2 South
(APOGEE-2S) at LCO and the new spectra comprise both observations of 260,594
new targets and additional epochs on targets included in previous DRs. The
majority of the targets are in the Milky Way galaxy, but DR17 also contains
observations of stars in the Large and Small Magellanic Clouds and eight dwarf
spheroidal satellites as well as integrated light observations of both M33 and
M31. Notably, DR17 contains 408,118 new spectra taken with the APOGEE-S
spectrograph at LCO; this brings the total APOGEE-2S observations to 671,379
spectra of 204,193 unique stars. DR17 also includes all previously released
APOGEE and APOGEE-2 spectra for a cumulative total of 2,659,178 individual
spectra, all of which have been re-reduced with the latest version of the
APOGEE data reduction and analysis pipeline (J. Holtzman et al. in prep.). In
addition to the reduced spectra, element abundances and stellar parameters are
included in this data release. APOGEE-2 is also releasing a number of VACs,
which are listed in Table 2.

  2. 2.

MaNGA and MaStar are releasing all scientific data products from the now-
completed surveys. This contains a substantial number of new galaxy and star
observations respectively, along with updated products for all observations
previously released in DR15 and before. These updated data products include
modifications to achieve sub-percent accuracy in the spectral line-spread
function, revised flux calibration, and Data Analysis Pipeline (DAP) products
that now use stellar templates constructed from the MaStar observations to
model the MaNGA galaxy stellar continuum throughout the full optical and near-
infrared (NIR) wavelength range. MaNGA reached its target goal of observing
more than 10,000 nearby galaxies, as well as a small number of non-galaxy
targets, while bright time observations enable MaStar to collect spectra for
almost 30,000 stars through the MaNGA instrument. MaNGA is also releasing a
number of VACs (Table 2).

  3. 3.

There is no change in the main survey eBOSS data released since DR16, when a
total of 1.4 million eBOSS spectra were released, completing its main survey
goals. However, a number of Value Added Catalogs (VACs) useful for
cosmological and other applications are released in DR17. The TDSS survey also
released its complete dataset in DR16. However, on-going eBOSS-like
observations of X-ray sources under the SPIDERS program and continued
monitoring of quasars under the reverberation mapping program (SDSS-RM) are
released in DR17.

  4. 4.

DR17 also includes data from all previous SDSS data releases. All MaNGA, BOSS,
eBOSS, APOGEE and APOGEE-2 spectra that were previously released have all been
reprocessed with the latest reduction and analysis pipelines. eBOSS main
survey data were last released in DR16 (Ahumada et al., 2020), SDSS-III
MARVELS spectra were finalized in DR12 (Alam et al., 2015). SDSS Legacy
Spectra were released in its final form in DR8 (Aihara et al., 2011), and the
SEGUE-1 and SEGUE-2 surveys had their final reductions released with DR9 (Ahn
et al., 2012). The SDSS imaging had its most recent release in DR13 (Albareti
et al., 2017), when it was recalibrated for eBOSS imaging purposes.

A numerical overview of the total content of DR17 is given in Table 1. An
overview of the value-added catalogs that are new or updated in DR17 can be
found in Table 2; adding these to the VACs previously released in SDSS, the
total number of VACs in SDSS as of DR17 is now 63 (DR17 updates 14 existing
VACs and introduces 11 new ones). DR17 also contains the VACs that were first
published in the mini-data release DR16+ on 20 June 2020. DR16+ did not
contain any new spectra, and consisted of VACs only. Most of the VACs in DR16+
were based on the final eBOSS DR16 spectra, and these include large scale
structure and quasar catalogs. In addition, DR16+ contained three VACs based
on DR15 MaNGA sample. The DR16+ VACs can be found in Table 2, and are
described in more detail in the sections listed there.

Table 2New or Updated Value Added Catalogs (DR16+ where noted, otherwise new or updated for DR17)  Name (see Section for Acronym definitions) | Section | Reference(s)
---|---|---
APOGEE-2
Open Cluster Chemical Abundances and Mapping catalog | §4.4.1 |  Frinchaboy et al. (2013); Donor et al. (2018, 2020),
(OCCAM) |  | N. Myers et al. (in prep.)
Red-Clump (RC) Catalog | §4.4.1 | Bovy et al. (2014)
APOGEE-Joker | §4.4.1 | A. Price-Whelan et al. (in prep.)
Double lined spectroscopic binaries in APOGEE spectra | §4.4.1 | Kounkel et al. (2021)
StarHorse for APOGEE DR17 + Gaia EDR3 | §4.4.2 | Queiroz et al. (2020)
AstroNN | §4.4.2 | Leung & Bovy (2019a, b); Mackereth et al. (2019a)
APOGEE Net: a unified spectral model | §4.4.3 | Olney et al. (2020); Sprague et al. (2022)
APOGEE on FIRE Simulation Mocks | §4.4.4 |  Sanderson et al. (2020), Nikakhtar et al. (2021)
MaNGA
NSA Images (DR16+) | §5.5.1 | Blanton et al. (2011); Wake et al. (2017)
SWIFT VAC (DR16+) | §5.5.1 | Molina et al. (2020)
Galaxy Zoo: 3D | §5.5.2 | Masters et al. (2021)
Updated Galaxy Zoo Morphologies (SDSS, UKIDSS and DESI) | §5.5.2 | Hart et al. (2016); Walmsley et al. (2022)
Visual Morphologies from SDSS + DESI images (DR16+) | §5.5.2 | Vázquez-Mata et al. (2021)
PyMorph DR17 photometric catalog | §5.5.2 | Domínguez Sánchez et al. (2022)
Morphology Deep Learning DR17 catalog | §5.5.2 | Domínguez Sánchez et al. (2022)
PCA VAC (DR17) | §5.5.3 |  Pace et al. (2019a, b).
Firefly Stellar Populations | §5.5.3 |  Goddard et al. (2017), Neumann et al. (in prep.)
Pipe3D | §5.5.3 | Sánchez et al. (2016, 2018)
HI-MaNGA DR3 | §5.5.4 | Masters et al. (2019); Stark et al. (2021)
The MaNGA AGN Catalog | §5.5.5 | Comerford et al. (2020)
Galaxy Environment for MaNGA (GEMA) | §5.5.6 | Argudo-Fernández et al. (2015)
Spectroscopic Redshifts for DR17 | §5.5.7 |  Talbot et al. (2018), M. Talbot et al. (in prep.)
Strong Gravitational Lens Candidate Catalog | §5.5.8 | M. Talbot et al. (in prep.)
MaStar
Photometry Crossmatch | §6.4 | R. Yan et al. (in prep.)
Stellar Parameters | §6.5 | R. Yan et al. (in prep.)
eBOSS
ELG (DR16+) | §7.1.1 | Raichoor et al. (2017, 2021)
LRG (DR16+) | §7.1.1 | Prakash et al. (2016); Ross et al. (2020)
QSO (DR16+) | §7.1.1 | Myers et al. (2015); Ross et al. (2020)
DR16 Large-scale structure multi-tracer EZmock catalogs | §7.1.2 | Zhao et al. (2021)
DR16Q catalog (DR16+) | §7.1.3 | Lyke et al. (2020)
Ly$\alpha$ catalog (DR16+) | §7.1.4 | du Mas des Bourboux et al. (2020)
Strong Gravitational Lens Catalog (DR16+) | §7.2.1 | Talbot et al. (2021)
ELG-LAE Strong Lens Catalog | §7.2.2 | Shu et al. (2016)
Cosmic Web Environmental Densities from MCPM | §7.2.3 | Burchett et al. (2020)

##  3\. Data Access

There are various ways to access the SDSS DR17 data products, and an overview
of all these methods is available on the SDSS website
https://www.sdss.org/dr17/data_access/, and in Table 3. In general, the best
way to access a data product will depend on the particular data product and
what the data product will be used for. We give an overview of all different
access methods below, and also refer to tutorials and examples on data access
available on this website: https://www.sdss.org/dr17/tutorials/.

Table 3Summary of Methods for Accessing SDSS Data  Name | Brief Description
---|---
SAS | Science Archive Server - direct access to reduced images and spectra, and downloadable catalog files
SAW | Science Archive Webservers - for visualisation of images and 1D spectra
CAS | Catalog Archive Server - for optimized access to searchable catalog data from a database management system
SkyServer | web app providing visual browsing and synchronous query access to the CAS
Explore | a visual browsing tool in SkyServer to examine individual objects
Quicklook | a more succinct version of the Explore tool in SkyServer
CasJobs | batch (asynchronous) query access to the CAS
SciServer | science platform for server-side analysis. Includes browser-based and Jupyter notebook access to SkyServer, CasJobs and Marvin
Marvin | a webapp and python package to access MaNGA data
SpecDash | a SciServer tool to visualize 1D spectra with standalone and Jupyter notebook access
Voyages | an immersive introduction to data and access tools for K-12 education purposes

For those users interested in the reduced images and spectra of the SDSS, we
recommend that they access these data products through the SDSS Science
Archive Server (SAS, https://data.sdss.org/sas/). These data products were all
derived through the official SDSS data reduction pipelines, which are also
publicly available through SVN or GitHub
(https://www.sdss.org/dr17/software/). The SAS also contains the VACs that
science team members have contributed to the data releases (see Table 2), as
well as raw and intermediate data products. All files available through the
SAS have a data model that explains their content
(https://data.sdss.org/datamodel/). Data products can be downloaded from the
SAS either directly through browsing, or by using methods such as wget, rsync
and Globus Online (see https://www.sdss.org/dr17/data_access/bulk, for more
details and examples). For large data downloads, we recommend the use of
Globus Online. Since SDSS data releases are cumulative, in that data products
released in earlier data releases are included in DR17, and will have been
processed by the latest available pipelines, we reiterate that users should
always use the latest data release, as pipelines have often been updated to
improve their output and fix previously known bugs.

The Science Archive Webservers (SAW) provides visualisations of most of the
reduced images and data products available on the SAS. The SAW offers the
option to display spectra with their model fits, and to search spectra based
on a variety of parameters (e.g. observing program, redshift, coordinates).
These searches can be saved as permalinks, so that they can be consulted again
in the future and be shared with collaborators. All SAW webapps are available
from https://dr17.sdss.org/, and allow for displaying and searching of images
(SDSS-I/II), optical single-fiber spectra (SDSS-I/II, SEGUE, BOSS and eBOSS),
infrared spectra (APOGEE-1 and APOGEE-2), and MaStar stellar library spectra.
Images and spectra can be downloaded through the SAW, and previous data
releases are available back to DR8. The SAW also offers direct links to
SkyServer Explore pages (see below).

The MaNGA integral-field data is not incorporated in the SAW due to its more
complex data structure, and can instead be accessed through Marvin
(https://dr17.sdss.org/marvin/; Cherinka et al. 2019). Marvin offers not only
visualisation options through its web interface, but also allows the user to
query the data and analyze data products remotely through a suite of Python
tools. Marvin also offers access to various MaNGA value added catalogs, as
described in §5.5. Marvin’s Python tools are available through pip-install,
and installation instructions as well as tutorials and examples are available
here: https://sdss-marvin.readthedocs.io/en/stable/. No installation is
required to use Marvin’s Python tools in SciServer, as described later in this
section and in §5.3.

Catalogs of derived data products are available on the SAS, but can be
accessed more directly through the Catalog Archive Server (CAS, Thakar et al.,
2008). These include photometric and spectroscopic properties, as well as some
value added catalogs. The SkyServer webapp (https://skyserver.sdss.org) allows
for visual inspection of objects using e.g. the QuickLook and Explore tools,
and is also suitable for synchronous SQL queries in the browser. Tutorials and
examples explaining the SQL syntax and how to query in SkyServer are available
at http://skyserver.sdss.org/en/help/docs/docshome.aspx. For DR17, the
SkyServer underwent a significant upgrade, which includes a completely
redesigned user interface as well as migration of the back end to a platform
independent, modular architecture. Although SkyServer is optimal for smaller
queries that can run in the browser, for larger ones we recommend using
CASJobs (https://skyserver.sdss.org/casjobs). CASJobs allows for asynchronous
queries in batch mode, and offers the user free storage space for query
results in a personal database (MyDB) for server-side analysis that minimizes
data movement (Li & Thakar, 2008).

SkyServer and CASJobs are now part of the SciServer science platform
(Taghizadeh-Popp et al., 2020, https://www.sciserver.org), which is accessible
with free registration on a single-sign-on portal, and offers server-side
analysis with Jupyter notebooks in both interactive and batch mode, via
SciServer Compute. SciServer is fully integrated with the CAS, and users will
be able to access the data and store their notebooks in their personal account
(shared with CASJobs). SciServer offers data and resource sharing via its
Groups functionality that greatly facilitates its use in the classroom, to
organize classes with student, teacher and teaching assistant privileges.
Several SciServer Jupyter notebooks with use cases of SDSS data are available
through the SDSS education webpages (https://www.sdss.org/education/), some of
which have been used by SDSS members in college-level based courses as an
introduction to working with astronomical data. SciServer has prominently
featured in the “SDSS in the Classroom” workshops at AAS meetings.

Users can now analyze the MaNGA DR17 data in SciServer, using the Marvin suite
of Python tools. SciServer integration enables users to use the access and
analysis capabilities of Marvin without having a local installation. In the
SciServer Compute system222https://www.sciserver.org/about/compute/, the MaNGA
dataset is available as an attachable MaNGA Data Volume, with the Marvin
toolkit available as a loadable Marvin Compute Image. Once loaded, the Marvin
package along with a set of Marvin Jupyter example notebooks and tutorials are
available on the compute platform.

With DR17, we are also releasing in SciServer a new feature called SpecDash
(Taghizadeh-Popp, 2021) to interactively analyze and visualize one-dimensional
optical spectra from SDSS Legacy and eBOSS surveys, and soon from APOGEE as
well. SpecDash is available both as stand-alone
website333https://specdash.idies.jhu.edu/, and as a Jupyter notebook widget in
SciServer.

Users can load and compare multiple spectra at the same time, smooth them with
several kernels, overlay error bars, spectral masks and lines, and show
individual exposure frames, sky background and model spectra. For analysis and
modeling, spectral regions can be interactively selected for fitting the
continuum or spectral lines with several predefined models. All spectra and
models shown in SpecDash can be downloaded, shared, and then uploaded again
for subsequent analysis and reproducibility. Although the web-based version
shares the same functionality as the Jupyter widget version, the latter has
the advantage that users can use the SpecDash python library to
programmatically load any kind of 1-D spectra, and analyze or model them using
their own models and kernels.

All tools and data access points described above are designed to serve a wide
range of users from undergraduate level to expert users with significant
programming experience. In addition, Voyages (https://voyages.sdss.org/)
provides an introduction to astronomical concepts and the SDSS data for less
experienced users, and can also be used by teachers in a classroom setting.
The Voyages activities were specifically developed around pointers to K-12 US
science standards, and a Spanish language version of the site is available at
https://voyages.sdss.org/es/.

##  4\. APOGEE-2 : Full Release

The central goal of APOGEE is to map the chemodynamics of all structural
components of the Milky Way Galaxy via near-twin, multiplexed NIR high-
resolution spectrographs operating simultaneously in both hemispheres
(APOGEE-N and APOGEE-S spectrographs respectively; both described in Wilson et
al., 2019). DR17 constitutes the sixth release of data from APOGEE, which has
run in two phases (APOGEE-1 and APOGEE-2) spanning both SDSS-III and SDSS-IV.
As part of SDSS-III, the APOGEE-1 survey operated for approximately 3 years
from August 2011 to July 2014 using the 2.5-m Sloan Foundation Telescope at
APO. At the start of of SDSS-IV, APOGEE-2 continued its operations in the
Northern Hemisphere by initiating a $\sim$6-year survey (APOGEE-2N). Thanks to
unanticipated on-sky efficiency, APOGEE-2N operations concluded in November
2020 with an effective $\sim$7.5 years of bright time observations, with many
programs expanded from their original 6-year baseline. In April 2017,
operations began with the newly built APOGEE-S spectrograph and associated
fiber plugplate infrastructure on the 2.5-m Irénée du Pont Telescope at LCO;
APOGEE-2S observations concluded in January 2021. A full overview of the
APOGEE-1 scientific portfolio and operations was given in Majewski et al.
(2017) and a parallel overview for APOGEE-2 is forthcoming (S. Majewski et
al., in prep.).

The APOGEE data in DR17 encompass all SDSS-III APOGEE-1 and SDSS-IV APOGEE-2
observations acquired with both instruments from the start of operations at
APO in SDSS-III (September 2011) through the conclusion of SDSS-IV operations
at APO and LCO (in November 2020 and January 2021, respectively). Compared to
the previous APOGEE data release (DR16), DR17 contains roughly two additional
years of observations in both hemispheres; this doubles the number of targets
observed from APOGEE-2S (see Table 1).

DR17 contains APOGEE data and information for 657,135 unique targets, with
372,458 of these (57%) as part of the main red star sample that uses a simple
selection function based on de-reddened colors and magnitudes (for more
details see Zasowski et al., 2013, 2017). The primary data products are: (1)
reduced visit and visit-combined spectra, (2) radial velocity measurements,
(3) atmospheric parameters (eight in total), and (4) individual element
abundances (up to 20 species). Approximately 2.6 million individual visit
spectra are included in DR17; 399,505 sources have three or more visits (54%)
and 35,009 sources (5%) have ten or more visits.

The final APOGEE survey map is shown in Figure 2, where each circle represents
a single “field” that is color-coded by survey phase: APOGEE-1 (cyan),
APOGEE-2N (blue), or APOGEE-2S (red). The difference in field-of-view between
APOGEE-N and APOGEE-S is visible by the size of the symbol, with each APOGEE-S
field spanning 2.8 deg2 and APOGEE-N spanning 7 deg2 (for the instrument
descriptions, see Wilson et al., 2019). Those fields with any new data in DR17
are encircled in black; new data can either be fields observed for the first
time or fields receiving additional epochs. The irregular high Galactic
latitude coverage is largely due to piggyback “co-observing” with MaNGA during
dark time. Notably, these cooperative operations resulted in observations of
an additional 162,817 targets, or 22% of the total DR17 targets ($\sim$30% of
targets in APOGEE-2), which is a comparable number of targets as were observed
in all of APOGEE-1.

Figure 2.— The DR17 final APOGEE sky coverage shown in Galactic coordinates
with fields color-coded by the survey phase in which the field was observed:
APOGEE-1 (cyan), APOGEE-2N (blue), and APOGEE-2S (red). The fiber plugplates
used with the APOGEE-N spectrograph have a 7 square degree field-of-view while
those used with the APOGEE-S spectrograph have a 2.8 square degree field of
view. Those fields with any new observations in DR17 are highlighted with a
black outline.  Figure 3.— A sky map in Galactic coordinates showing the
number of stars per APOGEE field. The disk is targeted with a more or less
systematic grid of pointings within $|b|<15\deg$. For $\ell<30\deg$ there is
more dense coverage of the bulge and inner Galaxy. The circle sizes reflect
the different field-of-view of APOGEE-N and APOGEE-S. The dense coverage at
the North Galactic Cap is due to co-observing with the MaNGA survey, which
contributed 22% of the targets in DR17.

A different visualization of the final field plan is given in Figure 3, where
now each field is color-coded by the number of unique stars targeted in each
field. APOGEE plates have 300 fibers, but APOGEE targeting uses a “cohorting”
strategy by which exposure is accumulated over many visits for the faintest
targets in a field while brighter targets are swapped in and out over time
(for a schematic see Zasowski et al., 2013, Figure 1 therein). Moreover, some
fields were included in multiple programs, like those in the _Kepler_
footprint, and as many as 1600 unique targets were accommodated in a single 7
deg2 APOGEE-2N field over the full span of the APOGEE-1 and APOGEE-2 observing
programs.

Extensive descriptions of the target selection and strategy are found in
Zasowski et al. (2013) for APOGEE-1 and in Zasowski et al. (2017) for
APOGEE-2. Details about the final target selection schemes used for APOGEE-2N
and APOGEE-2S, which evolved over time, are presented in Beaton et al. (2021)
and Santana et al. (2021), respectively.

###  4.1. DR17 Sample Highlights

DR17 represents the culmination of the APOGEE-2 program (and, indeed, all of
APOGEE) and presents a number of large, focused subsamples that are worth
noting briefly. DR17 contains over 18,000 targets in the TESS Northern
Continuous Viewing Zone (CVZ) and over 35,000 targets in the TESS Southern CVZ
(Ricker et al., 2016). In DR17, there are over 35,000 targets which are part
of 13 of the _Kepler_ K2 Campaigns and over 20,000 in the primary _Kepler_
field. In total, over 100,000 targets are also found in high-cadence, space-
based photometry programs. Among all scientific targeting programs, there are
more than 13,000 targets that have more than 18 individual epochs, spanning
all parts of the Galaxy.

DR17 includes extensive APOGEE coverage for numerous star clusters, including
29 open clusters, 35 globular clusters, and 18 young clusters. However,
detailed membership characterization identifies at least one possible member
in as many as 126 open clusters and 48 globular clusters, after accounting for
targets in Contributed and Ancillary Science programs (N. Myers et al., in
prep, R. Schiavon et al., in prep.). Thus, some observations exist in DR17 for
approximately 200 star clusters spanning a range of ages and physical
properties.

In addition, DR17 contains measurements of resolved stars from ten dwarf
satellite galaxies of the Milky Way (including the dwarf spheroidal systems
Boötes I, Sextans, Carina, Fornax, Sculptor, Sagittarius, Draco, and Ursa
Minor, as well as the Large and Small Magellanic Clouds); 14,000 of the over
20,000 targets toward dwarf satellites are in the Magellanic System. In
addition, DR17 contains integrated light observations of star clusters in
Fornax, M31, and M33 and of the central regions of M31 and of its
highest–surface brightness dwarf satellites.

###  4.2. APOGEE DR17 Data Products

The basic procedure for processing and analysis of APOGEE data is similar to
that from previous data releases (Abolfathi et al., 2018; Holtzman et al.,
2018; Jönsson et al., 2020), but a few notable differences are highlighted
here. More details are presented in J. Holtzman et al. (in prep.).

####  4.2.1 Spectral Reduction and Radial Velocity Determinations

Nidever et al. (2015) describes the original reduction procedure for APOGEE
data, and the various APOGEE Data Release papers present updates (Abolfathi et
al., 2018; Holtzman et al., 2018; Jönsson et al., 2020, J. Holtzman et al. in
prep.). For DR17, at the visit reduction level, a small change was made to the
criteria by which pixels are flagged as being potentially affected by poor sky
subtraction.

The routines for combination of the individual visit spectra were rewritten
for DR17 to incorporate a new radial velocity analysis, called Doppler
(Nidever et al., 2021). Doppler performs a least squares fit to a set of visit
spectra, solving simultaneously for basic stellar parameters ($T_{\rm eff}$,
$\log\leavevmode\nobreak\ g$, and [M/H]) and the radial velocity for each
visit. The fitting is accomplished by using a series of Cannon (Ness et al.,
2015; Casey et al., 2016) models to generate spectra for arbitrary choices of
stellar parameters across the Hertzsprung-Russell diagram (from 3500 K to
20,000 K in $T_{\rm eff}$); the Cannon models were trained on a grid of
spectra produced using Synspec (e.g., Hubeny & Lanz, 2017; Hubeny et al.,
2021) with Kurucz model atmospheres (Kurucz, 1979; Castelli & Kurucz, 2003;
Munari et al., 2005).  The primary output of Doppler are the radial
velocities; while the stellar parameters from Doppler are stored, they are not
adopted as the final values (see ASPCAP, §4.2.2 below). The Doppler routine
produces slightly better results for radial velocities in most cases, as
judged by scatter across repeated visits of stars. Details will be given in J.
Holtzman et al. (in prep), but, for example, for $\sim$ 85,000 stars that have
more than 3 visits, VSCATTER$<$ 1 km/s, TEFF$<$ 6000 K, and no additional data
since DR17, the median VSCATTER is reduced from 128 m/s to 96 m/s.

In addition to the new methodology, the radial velocities for faint stars were
improved. This was accomplished by making an initial combination of the visit
spectra using only the barycentric correction. This initial combination
provided a combined spectrum from which a radial velocity was determined. The
radial velocity for each individual visit was then determined separately, but
was required to be within 50 km/s of the original estimate. This yielded a
higher fraction of successful radial velocities for faint stars, as judged by
looking at targets in nearby dwarf spheroidal galaxies.

####  4.2.2 Atmospheric Parameter and Element Abundance Derivations

Stellar parameters and abundances are determined using the APOGEE Stellar
Parameters and Chemical Abundance Pipeline (ASPCAP, García Pérez et al. 2016)
that relies on the FERRE optimization code (Allende Prieto et al.,
2006).444https://github.com/sdss/apogee

The basic methodology of ASPCAP remained the same for DR17 as in previous
releases, but new synthetic spectral grids were created. These took advantage
of new, non-local thermodynamic equilibrium (NLTE) population calculations by
Osorio et al. (2020) for four elements: Na, Mg, K, and Ca; as discussed in
Osorio et al. (2020) the H-band abundance differences between LTE and NLTE
were always less than 0.1 dex. Adopting these calculations, however, required
the adoption of a different spectral synthesis code from that used in the last
several APOGEE data releases: for DR17, the Synspec code (e.g., Hubeny & Lanz,
2017; Hubeny et al., 2021) was adopted for the primary analysis instead of the
Turbospectrum code (Alvarez & Plez, 1998; Plez, 2012) used in previous
releases. This was not a straightforward choice because, while Synspec allows
the NLTE levels to be used, it calculates the synthetic spectra under the
assumption of plane parallel geometry, which becomes less valid for the
largest giant stars. On the other hand, Turbospectrum can use spherical
geometry, but does not accommodate NLTE populations to be specified.

DR17 uses multiple sub-grids to span from $T_{\rm eff}$=3000 K (M dwarf) to
$T_{\rm eff}$=20,000 K (BA), with $\log\leavevmode\nobreak\ g$ ranges from 0
to 5 (3 to 5 for the BA grid). The full details of these grids and the
reliability of the parameters as a function of stellar type are provided in J.
Holtzman et al. (in prep.). Modifications to the linelists used for the
syntheses are described in Smith et al. (2021), which is an augmentation to
prior linelist work for APOGEE (Shetrone et al., 2015; Hasselquist et al.,
2016; Cunha et al., 2017).

The ASPCAP results from the new Synspec grid are the primary APOGEE DR17
results and the majority of users will likely be satisfied with the results in
this catalog; only this primary catalog will be loaded into the CAS. However,
unlike prior releases, DR17 also includes supplemental analyses constructed
using alternate libraries that have different underlying physical assumptions.
The different analyses in DR17 are provided in separate summary files and
include:

  1. 1.

the primary library using Synspec including NLTE calculations for Na, Mg, K,
and Ca (with files on the SAS under dr17/synspec_rev1)555This is a revised
version of the dr17/synspec directories, correcting a minor problem with the
LSF convolution for a subset of stars observed at LCO, however, since Value
Added Catalogs were constructed with the original dr17/synspec we have
retained it for completness.;

  2. 2.

one created using Synspec, but assuming LTE for all elements (files under
dr17/synspec_lte);

  3. 3.

another created using Turbospectrum 20 (files under dr17/turbo20), using
spherical geometry for $\log\leavevmode\nobreak\ g$$<=$3;

  4. 4.

one created with Turbospectrum, but with plane parallel geometry (files under
dr17/turbo20_pp) for all stars.

All of the libraries use the same underlying MARCS stellar atmospheres for
stars with $T_{\rm eff}$$<$ 8000 K, computed with spherical geometry for
$\log\leavevmode\nobreak\ g$$<=$3\. A full description of these spectral grids
will be presented in J. Holtzman et al. (in prep.) and a focused discussion on
the differences between the libraries and the physical implications will be
presented in Y. Osorio et al. (in prep.). In summary, however, the differences
are subtle in most cases. We encourage those using the APOGEE DR17 results to
clearly specify the catalog version that they are using in their
analyses666Users may find the library version in the name of the summary file,
as well as in the ASPCAP_ID tag provided for each source in these files..

For DR17, we present 20 elemental abundances: C, C I, N, O, Na, Mg, Al, Si, S,
K, Ca, Ti, Ti II, V, Cr, Mn, Fe, Co, Ni, and Ce. In DR16, we attempted to
measure the abundances of Ge, Rb, and Yb, but given the poor results for
extremely weak lines, we did not attempt these in DR17. While we attempted
measurements of P, Cu, Nd, and 13C in DR17, these were judged to be
unsuccessful. Overall, the spectral windows used to measure the abundances
were largely unchanged, but several additional windows were added for Cerium,
such that the results for Ce appear to be significantly improved over those in
DR16.

As in DR16, both the raw spectroscopic stellar parameters as well as
calibrated parameters and abundances are provided.  Calibrated effective
temperatures are determined by a comparison to photometric effective
temperatures, as determined from the relations of (González Hernández &
Bonifacio, 2009), using stars with low reddening.  Calibrated surface
gravities are provided by comparison to a set of surface gravities from
asteroseismology (Serenelli et al., 2017, M. Pinsonneault et al. in prep.) and
isochrones (Berger et al., 2020). For DR17, the surface gravity calibration
was applied using a neural network, unlike previous data releases where
separate calibrations were derived and applied for different groups (red
giants, red clump, and main sequence) of stars.  The new approach eliminates
small discontinuities that were previously apparent, and is described in more
detail in J. Holtzman et al. (in prep.).  For the elemental abundances,
calibration just consists of a zeropoint offset (separately for dwarfs and
giants), determined by setting the median abundance [X/M] of solar metallicity
stars in the solar neighborhood with thin disk kinematics such that [X/M]=0.

Additional details on the ASPCAP changes are described in J. Holtzman et al.
(in prep.).

####  4.2.3 Additional data

Several other modifications were made for DR17.

  1. 1.

The summary data files for APOGEE that are available on the Science Archive
Server now include data from the Gaia Early Data Release 3 (EDR3) for the
APOGEE targets (Gaia Collaboration et al., 2021, 2016). Positional matches
were performed by the APOGEE team. More specifically, the following data are
included:

     * •

Gaia EDR3 identifiers (Gaia Collaboration et al., 2021),

     * •

Gaia EDR3 parallaxes and proper motions (Lindegren et al., 2021),

     * •

Gaia EDR3 photometry (Riello et al., 2021),

     * •

Gaia EDR3 RVs (Seabroke et al., 2021),

     * •

Distances and uncertainties following Bailer-Jones et al. (2021).

  2. 2.

Likely membership for a set of open clusters, globular clusters, and dwarf
spheroidal galaxies, as determined from position, radial velocity, proper
motion, and distance, is provided in a MEMBERS column. More specifically,
initial memberships were computed based on position and literature RVs, and
these are then used to determine proper motion and distance criteria.
Literature RVs were taken from:

     * •

APOGEE-based mean RVs for the well-sampled “calibration clusters” in Holtzman
et al. (2018),

     * •

mean RVs for globular clusters from Harris (2010)777This is the 2010 update to
the Harris (1996) catalog., and

     * •

mean RVs for dwarf spheroidal galaxies from McConnachie (2012).

Users interested in the properties of the clusters or satellite galaxies are
encouraged to do more detailed membership characterization and probabilities
(e.g., Masseron et al., 2019; Mészáros et al., 2020; Hasselquist et al., 2021,
Schiavon et al., in prep., Shetrone et al., in prep.)

  3. 3.

Some spectroscopic binary identification is provided through bits in the
STARFLAG and ASPCAPFLAG bitmasks. A more comprehensive analysis of
spectroscopic binaries is provided in a VAC (see §4.4.1 below) .

We encourage those utilizing these data in our summary catalogs to cite the
original references as given above.

###  4.3. Data Quality

The overall quality of the DR17 results for radial velocities, stellar
parameters, and chemical abundances is similar to that of previous APOGEE data
releases (full evaluation will be provided in Holtzman et al. in prep.).888The
web documentation contains the details of the data model. Morevoer, the
documentation communicates how data was flagged, including a brief list of
changes relative to prior releases. As in DR16, uncertainties for stellar
parameters and abundances are estimated by analyzing the scatter in repeat
observations of a set of targets.

Users should be aware that deriving consistent abundances across a wide range
of parameter space is challenging, so some systematic features and trends
arise. Users should be careful when comparing abundances of stars with
significantly different stellar parameters. Also, the quality of the abundance
measurements varies between different elements, across parameter space, and
with signal-to-noise.

Some regions of parameter space present larger challenges than others. In
particular, it is challenging to model the spectra of the coolest stars and,
while abundances are derived for the coolest stars in DR17, there seem to be
significant systematic issues for the dwarfs with $T_{\rm eff}$$<$ 3500 K such
that although we provide calibrated results in the PARAM array, we do not
populate the “named tags.” Separately, for warm/hot stars ($T_{\rm
eff}$$>$7000), information on many abundances is lacking in the spectra, and
uncertainties in the model grids at these temperatures may lead to systematic
issues with the DR17 stellar parameters.

As a demonstration of the quality and scientific potential of the data, Figure
4 shows a set of [Mg/Fe] versus [Fe/H] diagrams for different three-
dimensional spatial zones within the disk of the Milky Way, restricted to
giant-stars with 1 $<$ $\log\leavevmode\nobreak\ g$$<$ 2.5 to minimize
potential systematics or sampling bias.  Spectrophotometric distances to
individual stars are determined from Value Added Catalogs999In this
visualization, from the DistMass VAC to be released in 2022 that uses a Neural
Net at the parameter level to determine spectroscopic distances. and then are
used with stellar positions to determine the Galactocentric radius ($R_{G}$)
and height above the plane ($z$) for each individual star; this highlights the
scientific potential enabled via the analyses in the Value Added Catalogs. The
color coding indicates the orbital eccentricity based on calculations from
GalPy (Bovy, 2015) using Gaia EDR3 proper motions (Gaia Collaboration et al.,
2021) and APOGEE DR17 radial velocities. Figure 4 is a merging of similar
visualizations previously presented in Hayden et al. (2015) and Mackereth et
al. (2019b), such that the spatial zones of the former are merged with the
dynamical inference of the latter. The stars of the solar neighborhood (middle
panel, $7<R_{G}<9$) show two distinct chemical sequences, commonly referred to
the the low- and high- [$\alpha$/Fe] sequences that are also somewhat
dynamically distinct (apparent in the color-coding by orbital eccentricity).
The inner Galaxy, however, is dominated both by high-eccentricity (bulge-like
orbits) stars on the high-[$\alpha$/Fe] sequence just as the outer galaxy is
dominated by low-eccentricity (near circular orbits) stars on the
low-[$\alpha$/Fe] sequence, with some slight dependence on $z$. The relative
contributions of low-eccentricity versus high-eccentricity and
low-[$\alpha$/Fe] versus high-[$\alpha$/Fe] sequences shift throughout the
Galaxy. These spatial, chemical, and dynamical groupings provide evidence for
various disk-formation and disk-evolution scenarios (e.g., as discussed in
Hayden et al., 2015; Mackereth et al., 2019b, among others) that add
complexity and nuance to the canonical schemes.  .

Figure 4.— A series of [Mg/Fe] vs [Fe/H] plots from APOGEE DR17 for different
zones in the Milky Way. Distances from the DistMass VAC are used to determine
Galactocentric radius ($R_{G}$) and height above the plane ($z$). Points are
color-coded by orbital eccentricities as computed with GalPy (Bovy, 2015)
using Gaia EDR3 proper motions and APOGEE radial velocities.

###  4.4. APOGEE Value Added Catalogs

There are a large number of APOGEE-associated VACs in DR17. In what follows we
provide brief descriptions of each VAC along with references where the reader
can find more detail. Broadly speaking, APOGEE VACs can be split into
characterising special subsamples, like binary stars, open clusters, and
photometric variables, those which calculate stellar or orbital parameters for
all (or most) APOGEE target stars (e.g. Starhorse, APOGEEnet and others). We
also document the release of a mock catalog of APOGEE based on a
hydrodynamical simulation.

####  4.4.1 VACs Describing Categories of Objects in APOGEE

The first set of APOGEE VACs describe special categories of objects in APOGEE
data and in most cases provide additional information/characteristics for
these objects. They are:

  1. 1.

Open Cluster Chemical Abundances and Mapping catalog (OCCAM): The goal of
OCCAM is to leverage the APOGEE survey to create a large, uniform catalog of
open cluster chemical abundances and use these clusters to study Galactic
chemical evolution. The catalog contains average chemical abundances for each
cluster and membership probability estimates for APOGEE stars in the cluster
area. We combine proper motion (PM) and radial velocity (RV) measurements from
Gaia EDR3 (Gaia Collaboration et al., 2021) with RV and metallicity
measurements from APOGEE to establish cluster membership probabilities for
each star observed by APOGEE. The VAC includes 26,699 stars in the areas of
153 cataloged disk clusters. Detailed descriptions of the OCCAM survey,
including targeting and the methodology for membership determinations, are
presented in Frinchaboy et al. (2013), Donor et al. (2018), and Donor et al.
(2020). This third catalog from the OCCAM survey includes 44 new open
clusters, including many in the Southern hemisphere and those targeted
specifically in GC size ($R_{GC}$) ranges with little coverage in the DR16
catalog (specific targeting described in Beaton et al. 2021; Santana et al.
2021). Average RV, PM, and abundances for reliable ASPCAP elements are
provided for each cluster, along with the visual quality determination.
Membership probabilities based individually upon PM, RV, and [Fe/H] are
provided for each star, stars are considered 3$\sigma$ members if they have
probability $>0.01$ in all three membership dimensions 101010However, some
stars near the main sequence turn-off may “fail” the [Fe/H] cut due to
evolutionary diffusion effects (Souto et al., 2018, 2019). The results and
caveats from this VAC will be discussed thoroughly in N. Myers et al. (in
prep.).

  2. 2.

APOGEE Red-Clump (RC) Catalog: DR17 contains an updated version of the APOGEE
red-clump (APOGEE-RC) catalog. This catalog is created in the same way as the
previous DR14 and DR16 versions of the catalog, with a more stringent $\log g$
cut compared to the original version of the catalog (Bovy et al., 2014). The
catalog contains 50,837 unique stars, about 30% more than in DR16.  The
catalog is created using a spectrophotometric technique first presented in
Bovy et al. (2014) that results in a rather pure sample of red-clump stars
(e.g., minimal contamination from red-giant-branch, secondary-red-clump, and
asymptotic-giant-branch stars that have similar CMD and H-R positions). Bovy
et al. estimated a purity of $\sim$95%. The narrowness of the RC locus in
color-metallicity-luminosity space allows distances to the stars to be
assigned with an accuracy of 5%-10%, which exceeds the precision of
spectrophotometric distances in other parts of the H-R diagram. We recommend
users adopt the most recent catalog (DR17) for their analyses; additional
discussion on how to use the catalog is given in Bovy et al. (2014). While the
overall datamodel is similar to previous versions of the catalog, the proper
motions are from Gaia EDR3 (Gaia Collaboration et al., 2021;
Gaia_EDR3_Astrometry).

  3. 3.

APOGEE-Joker: The APOGEE-Joker VAC contains posterior samples for binary-star
orbital parameters (Keplerian orbital elements) for 358,350 sources with three
or more APOGEE visit spectra that pass a set of quality cuts as described in
A. Price-Whelan et al. (in prep.). The posterior samples are generated using
The Joker, a custom Monte Carlo sampler designed to handle the multi-modal
likelihood functions that arise when inferring orbital parameters with
sparsely-sampled or noisy radial velocity time data (Price-Whelan et al.,
2017). This VAC deprecates the previous iterations of the catalog (Price-
Whelan et al., 2018, 2020).

For 2,819 stars, the orbital parameters are well constrained, and the returned
samples are effectively unimodal in period. For these cases, we use the
sample(s) returned from The Joker to initialize standard MCMC sampling of the
Keplerian parameters using the time-series optimized MCMC code known as
exoplanet111111https://docs.exoplanet.codes/en/latest/ (Foreman-Mackey et al.,
2021) and provide these MCMC samples. For all stars, we provide a catalog
containing metadata about the samplings, such as the maximum a posteriori
(MAP) parameter values and sample statistics for the MAP sample. A. Price-
Whelan et al. (in prep.) describes the data analysis procedure in more detail,
and defines and analyzes a catalog of $\gtrsim$40,000 binary star systems
selected using the raw orbital parameter samples released in this VAC.

  4. 4.

Double lined spectroscopic binaries in APOGEE spectra: Generally, APOGEE
fibers capture a spectrum of single stars. Sometimes, however, there may be
multiple stars of comparable brightness with the sky separations closer than
the fiber radius whose individual spectra are captured by the same recorded
spectrum. Most often, these stars are double-lined spectroscopic binaries or
higher order multiples (SBs), but on an occasion they may also be chance line-
of-sight alignments of random field stars (most often observed towards the
Galactic center). Through analyzing the cross-correlation function (CCF) of
the APOGEE spectra, Kounkel et al. (2021) have developed a routine to
automatically identify these SBs using Gaussian deconvolution of the CCFs
(Kounkel, 2021)121212https://github.com/mkounkel/apogeesb2, and to measure RVs
of the individual stars. The catalog of these sources and the sub-component
RVs are presented here as a VAC. For the subset of sources that had a
sufficient number of measurements to fully characterize the motion of both
stars, the orbit is also constructed.

The data obtained though April/May 2020 were processed with the DR16 version
of the APOGEE radial velocity pipeline and this processing was made available
internally to the collaboration as an intermediate data release. All of the
SBs identified in this internal data release have undergone rigorous visual
vetting to ensure that every component that can be detected is included and
that spurious detections have been removed. However, the final DR17 radial
velocity pipeline is distinct from that used for DR16 (summarized above; J.
Holtzman et al. in prep.) and the reductions are sufficiently different that
they introduce minor discrepancies within the catalog. In comparison to DR16,
the DR17 pipeline limits the span of the CCF for some stars to a velocity
range around the mean radial velocity to ensure a more stable overall set of
RV measurements; on the other hand the DR16 pipeline itself may fail on a
larger number of individual visit spectra and thus not produce a full set of
outputs. For the sources that have both good parameters and a complete CCF
coverage for both DR16 and DR17, the widely resolved components of SBs are
generally consistent with one another; close companions that have only small
RV separations are not always identified in both datasets. For this reason,
SBs that could be identified in both the DR16 and DR17 reductions are kept as
separate entries in the catalog. Visual vetting was limited only to the data
processed with the DR16 pipeline (e.g., data through April/May 2020); the full
automatic deconvolutions of the DR17 CCFs are presented as-is.

####  4.4.2 VACs of Distances and other parameters

VACs providing distances and other properties (mostly related to orbital
parameters) are released (or re-released):

  1. 1.

StarHorse distances, extinctions, and stellar parameters for APOGEE DR17 +
Gaia EDR3: We combine high-resolution spectroscopic data from APOGEE DR17 with
broad-band photometric data from 2MASS, unWISE and PanSTARRS-1, as well as
parallaxes from Gaia EDR3. Using the Bayesian isochrone-fitting code StarHorse
(Santiago et al., 2016; Queiroz et al., 2018), we derive distances,
extinctions, and astrophysical parameters. We achieve typical distance
uncertainties of $\sim$ 5 % and extinction uncertainties in V-band amount to
$\sim$ 0.05 mag for stars with available PanSTARRS-1 photometry, and $\sim$
0.17 mag for stars with only infra-red photometry. The estimated StarHorse
parameters are robust to changes in the Galactic priors assumed and
corrections for Gaia parallax zero-point offset. This work represents an
update of DR16-based results presented in Queiroz et al. (2020).

  2. 2.

APOGEE-astroNN: The APOGEE-astroNN value-added catalog holds the results from
applying the astroNN deep-learning code to APOGEE spectra to determine stellar
parameters, individual stellar abundances (Leung & Bovy, 2019a), distances
(Leung & Bovy, 2019b), and ages (Mackereth et al., 2019a). For DR17, we have
re-trained all neural networks using the latest data, i.e., APOGEE DR17
results for the abundances, Gaia EDR3 parallax measurements, and an
intermediate APOKASC data set with stellar ages (v6.6.1, March 2020 using DR16
ASPCAP). Additionally, we augmented the APOKASC age data with low-metallicity
asteroseismic ages from Montalbán et al. (2021) to improve the accuracy of
ages at low metallicities; the Montalbán et al. (2021) analysis is similar to
that of APOKASC, but performed by an independent team. As in DR16, we correct
for systematic differences between spectra taken at LCO and APO by applying
the median difference between stars observed at both observatories. In
addition to abundances, distances, and ages, properties of the orbits in the
Milky Way (and their uncertainties) for all stars are computed using the fast
method of Mackereth & Bovy (2018) assuming the MWPotential2014 gravitational
potential from Bovy (2015). Typical uncertainties in the parameters are 35 K
in $T_{\rm eff}$, 0.1 dex in $\log\leavevmode\nobreak\ g$, 0.05 dex in
elemental abundances, 5 % in distance, and 30 % in age. Orbital properties
such as the eccentricity, maximum height above the mid-plane, radial, and
vertical action are typically precise to 4 to 8 %.

####  4.4.3 APOGEE Net: a unified spectral model

A number of different pipelines are available for extracting spectral
parameters from the APOGEE spectra. These pipelines generally manage to
achieve optimal performance for red giants and, increasingly, G & K dwarfs,
which compose the bulk of the stars in the catalog. However, the APOGEE2
catalog contains a number of parameter spaces that are often not well
characterized by the primary pipelines. Such parameter spaces include pre-main
sequence stars and low mass stars, with their measured parameters showing
systematic $T_{\rm eff}$ & $\log g$ deviations making them inconsistent from
the isochrones and the main sequence. OBA stars are also less well constrained
and in prior data releases many were classified as F dwarfs (due to grid-edge
effects) and have their $T_{\rm eff}$ underestimated in the formal results. By
using data-driven techniques, we attempt to fill in those gaps to construct a
unified model of APOGEE spectra. In the past, we have developed a neural
network, APOGEE Net (Olney et al., 2020), which was shown to perform well to
extract $T_{\rm eff}$, $\log g$, & [Fe/H] on all stars with $T_{\rm
eff}<$6,500 K, including pre-main sequence stars. We now expand these efforts
to also characterize hotter stars with 6,500$<T_{\rm eff}<$50,000 K. APOGEE
NET II is described in Sprague et al. (2022).

####  4.4.4 APOGEE FIRE VAC

Mock catalogs made by making simulated observations of sophisticated galaxy
simulations provide unique opportunities for observational projects, in
particular, the ability to test for or constrain the impact of selection
functions, field plans, and algorithms on scientific inferences. One of the
most realistic galaxy simulations to date is the Latte simulation suite, which
uses FIRE-2 (Hopkins et al., 2018) to produce galaxies in Milky Way-mass halos
in a cosmological framework (Wetzel et al., 2016). Sanderson et al. (2020)
translated three of the simulations into realistic mock catalogs (using three
solar locations, resulting in nine catalogs), known as the Ananke
simulations131313For data access see:
https://fire.northwestern.edu/ananke/#dm. Ananke contains key Gaia
measureables for the star particles in the simulations and these include
radial velocity, proper motion, parallax, and photometry in the Gaia bands as
well as chemistry (10 chemical elements are tracked in the simulation), and
other stellar properties. Because the input physics and the global structure
of the model galaxy are known, these mock catalogs provide an experimental
laboratory to make connections between the resolved stellar populations and
global galaxy studies.

In this VAC, Ananke is expanded to permit APOGEE-style sampling of the mock-
catalogs. For all observed quantities both the intrinsic, e.g., error-free,
and the observed values are reported; the observed values are the intrinsic
values convolved with an error-model derived from observational data for
similar object types. As described in Nikakhtar et al. (2021), Ananke mock-
catalogs now contain: (i) 2MASS ($JHK_{s}$) photometry and reddening, (ii)
abundance uncertainties following APOGEE DR16 performance (following Poovelil
et al., 2020; Jönsson et al., 2020), and (iii) a column that applies a basic
survey map (Zasowski et al., 2013, 2017; Beaton et al., 2021; Santana et al.,
2021). The full mock-catalogs are released such that users can impose their
own selection function to constructs a mock APOGEE survey in the simulation.
Mock-surveys can then be used to test the performance of methods and
algorithms to recover the true underlying galactic physics as demonstrated in
Nikakhtar et al. (2021).

##  5\. MaNGA: Full Release of Final Sample

The MaNGA survey (Bundy et al., 2015) uses a custom-built set of hexagonal
integral field unit (IFU) fiber bundles (Drory et al., 2015) to feed
spectroscopic fibers into the BOSS spectrograph (Smee et al., 2013). Over its
operational lifetime, MaNGA has successfully met its goal of obtaining
integral field spectroscopy for $\sim$ 10,000 nearby galaxies (Law et al.,
2015; Yan et al., 2016a) at redshift $z\sim 0.03$ with a nearly flat
distribution in stellar mass (Wake et al., 2017).

DR17 contains all MaNGA observations taken throughout SDSS-IV, and more than
doubles the sample size of fully reduced galaxy data products previously
released in DR15 (Aguado et al., 2019). These data products include raw data,
intermediate reductions such as flux-calibrated spectra from individual
exposures, and final calibrated data cubes and row-stacked spectra (RSS)
produced using the MaNGA Data Reduction Pipeline (DRP; Law et al., 2016,
2021a; Yan et al., 2016b).

DR17 includes DRP data products (see §5.1) for 11,273 MaNGA cubes distributed
amongst 674 plates. 10,296 of these data cubes are for “traditional” MaNGA
type galaxies, and 977 represent data cubes associated with non-standard
ancillary programs (targeting a variety of objects including globular
clusters, faint galaxies and intracluster light in the Coma cluster,
background reference sky, and also tiling of the large nearby galaxies M31 and
IC342; see §5.4 for more details). Of the 10,296 galaxy cubes, 10,145 have the
highest data quality with no warning flags indicating significant issues with
the data reduction process. These 10,145 data cubes correspond to 10,010
unique targets (as identified via their MANGAID) with a small number of repeat
observations taken for cross-calibration purposes (each has an individual
plate-ifu code, MANGAID needs to be used to identify unique galaxies). As in
previous releases, DR17 also includes the release of derived spectroscopic
products (e.g., stellar kinematics, emission-line diagnostic maps, etc.) from
the MaNGA Data Analysis Pipeline (DAP; Belfiore et al., 2019; Westfall et al.,
2019); see §5.2. Additionally, DR17 contains the final data release for the
MaNGA Stellar Library (MaStar; Yan et al., 2019, and §6), which includes
calibrated 1D spectra for 28,124 unique stars spanning a wide range of stellar
types.

We illustrate the sky footprint of MaNGA galaxies released in DR17 in Figure
5, along with colored boxes indicating the locations of a selection of other
galaxy surveys, namely the HI surveys Apertif (K. Hess et al. in prep) and
ALFALFA (or Arecibo Legacy Fast ALFA, Haynes et al. 2018; also see §5.5.4 for
more HI followup); IR surveys like Herschel-ATLAS, (H-ATLAS, Smith et al.
2017), the UKIRT Infrared Deep Sky Survey, (UKIDSS, Lawrence et al. 2007), and
other optical surveys, like Galaxy and Mass Assembly Survey (GAMA, Liske et
al. 2015), the footprint of which includes most of the SAMI IFU observations,
(Croom et al., 2021, in total, 74 galaxies are observed by both MaNGA and
SAMI) and Hyper Suprime-Cam (HSC, Aihara et al. 2019). In some cases the
prioritization of which MaNGA plates to observe was driven by the availability
of these ancillary data (e.g. note how observed plates fill in parts of the
UKIDSS footprint). MaNGA plates in an earlier projected footprint of Apertif
were also prioritized but changes in Apertif observation plans has
significantly reduced the final overlap.

Figure 5.— DR17 final MaNGA survey area; blue tiles indicate observed fields
(plates), grey tiles indicate potential fields from which the MaNGA final
sample was drawn. Colored boxes indicate the regions observed by a variety of
other surveys as described in the text.

###  5.1. MaNGA Data Reduction Pipeline and Products

The MaNGA DRP has evolved substantially throughout the survey across a variety
of both public (DR) and internal (“MaNGA Product Launch”, or MPL) data
releases. A summary of these various DRP versions and the number of unique
galaxies in each is given by Law et al. (2021a, see their Table 1). These
authors also provide a detailed description of the differences in the DRP for
DR17 compared to previous releases.141414Strictly Law et al. (2021a) describe
the team-internal data release MPL-10, but these data are practically
identical to the final public data release DR17 (which is the team internal
release MPL-11) in everything except the total number of galaxies. In brief,
changes in the DR17 data products compared to DR15 include:

  1. 1.

Updated spectral line-spread function (LSF): Many stages of the pipeline have
been rewritten to further improve the accuracy of the LSF estimate, which is
now good to better than 1%. As demonstrated by Law et al. (2021a) by
comparison against observations with higher-resolution spectrographs, this
allows MaNGA emission-line velocity dispersions to be reliable down to 20 km
s-1 at signal-to-noise ratio (SNR) above 50, which is well below the 70 km s-1
instrumental resolution.

  2. 2.

Multiple pipeline changes have affected the overall MaNGA survey flux
calibration. The most significant changes included adoption of a different
extinction model for the calibration standard stars and correction for a few-
percent scale error in lab measurements of the MaNGA fiber bundle metrology
using on-sky self calibrations (see Law et al., 2021a, their Appendix A).

  3. 3.

New data quality flags have been defined to better identify potential
reduction problems. These include a new UNUSUAL data quality bit to identify
cubes that are different from ordinary data quality but still useful for many
analyzes (e.g., that may be missing a fraction of the field of view due to
hardware problems). These are distinct from the previously-defined CRITICAL
data quality bit that indicates data with significant problems that should
preclude it from most scientific analyzes ($<1$% of the total sample).

  4. 4.

Introduction of a new processing step to detect and subtract bright electronic
artifacts (dubbed the “blowtorch”) arising from a persistent electronic
artifact within the Charge-coupled devices (CCDs) in one of the red cameras
during the final year of survey operations (see Law et al., 2021a, their
Appendix B).

###  5.2. MaNGA Data Analysis Pipeline and Products

In this section we describe two specific changes to the DAP analysis between
MaNGA data released in DR15 and DR17. The first is a change in the stellar
continuum templates used for the emission line measurements; this change only
affects emission line measurements and does not affect stellar kinematic
measurements. The second is the addition of new spectral index measurements
more appropriate for stacking analyzes and coaddition of spaxels; the
previously existing spectral index measurements are not affected by this
addition.

The MaNGA Data Analysis Pipeline (DAP) as a whole is discussed extensively in
the DR15 paper (Aguado et al., 2019) and in Westfall et al. (2019), Belfiore
et al. (2019), and Law et al. (2021a). The last provides a summary of other
improvements made to the DAP since DR15.

The SDSS data release website (https://www.sdss.org/) provides information on
data access and changes to the DAP data models in DR17 for its major output
products. Further information can be found in the documentation of the code
base.151515https://sdss-mangadap.readthedocs.io/en/latest/

####  5.2.1 Stellar Continuum Templates

In DR17, we use different spectral templates to model the galaxy continuum for
emission line measurements than we use for stellar kinematics measurements. In
DR15, we used the same templates in both cases, but as discussed by Law et al.
(2021a), these template sets diverged starting with our ninth internal data
set (MPL-9; between DR15 and DR17). For the emission line measurements, the
new templates are based on the MaStar survey, allowing us to take advantage of
the full MaNGA spectral range (3600-10000 Å) and, e.g., model the [S
III]$\lambda\lambda$9071,9533Å doublet and some of the blue Paschen lines. For
the stellar kinematics measurements, we have continued to use the same
templates used in DR15, the MILES-HC library, taking advantage of its modestly
higher spectral resolution than MaStar. Since MILES only spans between 3575 to
7400 Å, this means MaNGA stellar kinematics do not include, e.g.,
contributions from the calcium near-infrared triplet near 8600 Å.

In DR17, we provide DAP emission line measurements based on two different
continuum template sets, both based on the MaStar Survey (Yan et al., 2019,
and §6), and referred to as MASTARSSP and MASTARHC2. There are four different
analysis approaches, indicated by DAPTYPE. Three use MASTARSSP, with three
different spatial binning approaches, and the fourth uses MASTARHC2.

The template set referred to as the MASTARSSP library by the DAP are a subset
of simple-stellar-population (SSP) models provided by Maraston et al. (2020).
Largely to decrease execution time, we down-selected templates from the larger
library provided by Maraston et al. (2020) to only those spectra with a
Salpeter Initial Mass Function (IMF) and the following grid in SSP age and
metallicity, for a total of 54 spectra:

  1. 1.

Age/[1 Gyr] = 0.003, 0.01, 0.03, 0.1, 0.3, 1, 3, 9, 14

  2. 2.

$\log(Z/Z_{\odot})$ = -1.35, -1., -0.7, -0.33, 0, 0.35.

Extensive testing was done to check differences in stellar-continuum fits
based on this choice; small differences that were found are well within the
limits described by Belfiore et al. (2019). Section 5.3 of Law et al. (2021b)
show further analysis, including a direct comparison of results for the BPT
emission-line diagnostics plots when using either the MASTARHC2 or MASTARSSP
templates showing that the templates have a limited effect on their analysis.
Importantly, note that the DAP places no constraints on how these templates
can be combined (e.g., unlike methods which use the Penalized PiXel-Fitting,
or pPXF; Cappellari & Emsellem 2004; Cappellari 2017, implementation of
regularized weights), and the weight applied to each template is not used to
construct luminosity-weighted ages or metallicities for the fitted spectra.
The use of the SSP models, as opposed to spectra of single stars, is meant
only to impose a physically relevant prior on the best-fitting continua, even
if minimally so compared to more sophisticated stellar-population modeling.

The template set referred to as the MASTARHC2161616MASTARHC2 was the second of
two library versions based on hierarchical clustering (HC) of MaStar spectra.
MASTARHC1 is also available from the DAP code repository, but it was only used
in the processing for MPL-9. library by the DAP is a set of 65 hierarchically
clustered templates based on $\sim$2800 MaStar spectra from MPL-10. Only one
of the four DAPTYPEs provided in DR17 uses these templates; however, we note
that the results based on these templates are the primary data sets used by
Law et al. (2021b, a) to improve the DRP (see above). The approach used to