11institutetext:  Departament de Física Quàntica i Astrofísica, Institut de
Ciències del Cosmos, Universitat de Barcelona, IEEC-UB, Martí i Franquès, 1,
E-08028 Barcelona, Spain. 22institutetext: Departament de Física i Enginyeria
Nuclear, Universitat Politècnica de Catalunya, Av. Eduard Maristany, 16,
E-08019 Barcelona, Spain. 33institutetext: Grantecan S.A., Centro de
Astrofísica de La Palma, Cuesta de S. José, E-38712 Breña Baja, La Palma,
Spain. 44institutetext: Instituto de Astrofísica de Canarias, Via Láctea s/n,
E-38200 La Laguna, Tenerife, Spain. 55institutetext: Departamento de
Astrofísica, Universidad de La Laguna, E-38205 La Laguna, Tenerife, Spain.

#  A survey of IRAS young stellar object candidates:
searching for large-scale Herbig-Haro objects ††thanks:  Based on observations
obtained at the Centro Astronómico Hispano-Alemán de Calar Alto (CAHA), Spain.

Rosario López 11 Angels Riera 22Deceased on 2017 September 27Deceased on 2017
September 27 Robert Estalella 11 Gabriel Gómez 334455

(Version 2021 / Received / Accepted )

###### Abstract

Context.  Jets and outflows are associated with young stellar objects across
the stellar mass spectrum, from brown dwarf protostars to massive, Ae/Be
stars. Frequently, the jet morphology is spatially discontinuous because of
the temporal variability of the ejection from the driving source. Images
covering a wide field of view around the jet driving-source are useful to map
the large-scale jet emission and to explore the mass ejection history.

Aims.  The aim of this work was to search for large-scale optical Herbig-Haro
(HH) objects lying in a wide field around a sample of IRAS sources, candidates
to trace young stellar objects.

Methods.  Deep, narrow-band images through the H$\alpha$ and [S ii] emission
lines, and through an off-line continuum filter, covering a wide ($\sim
15^{\prime}$) field around the IRAS targets were acquired. The images in the
three filters were analyzed to identify shock-excited line emission (i.e., HH)
in contrast to scattered line emission.

Results.  New images of a sample of fifteen IRAS sources, obtained in an
homogeneous way are presented. HH emission was detected in six fields, and the
astrometry of the knot features is given. The nature of the extended emission
as scattered emission around nine of the IRAS targets is confirmed. For seven
IRAS sources, with unclear optical counterpart, a more plausible counterpart
is proposed. A refined value of the source distance is reported for seven
targets. An update of the main data available for each of the sampled fields,
including images from public data archives, is also presented.

###### Key Words.:

ISM: general – ISM: jets and outflows – Stars: formation

##  1 Introduction

Protostellar jets and outflows are found everywhere in star forming regions as
fundamental events occurring during the star formation process. They are
believed to regulate processes such as the removal of angular momentum excess
from the star-disk system, and the dispersion of the parent cloud. They are
observed in all evolutionary stages of young stellar objects (YSOs) where
accretion is occurring, from Class 0 to Class III, and across the stellar mass
spectrum, from brown dwarf protostars (Whelan et al., 2005; Riaz et al., 2017)
to massive, high luminosity young stars (Guzmán et al, 2012), and are detected
over a wide wavelength range through continuum emission and line emission from
molecular, neutral and ionized atomic transitions.

Herbig-Haro objects (HHs) are the optical manifestation of outflow events.
They are small shock-excited nebulae visible in low excitation lines (eg. [O
i], H$\alpha$, [S ii]) produced by the radiative cooling in post-shock zones.
Most HHs appear as a string of knots aligned in a highly collimated jet (HH-
jet) ending in a bright bow-shock where the jet rams into the surrounding
medium. The spatial scales covered by the HH-jets range from a few au, in the
case of microjets of T Tauri stars (Agra-Amboage et al., 2011) to several
parsecs (giant Herbig-Haro jets, Devine et al., 1999; Reipurth et al., 2019).
The knots trace internal shocks driven by velocity ejection variability.
Frequently the jet morphology shows discontinuities in its spatial
distribution, which is usually attributed to the temporal variability of the
ejection material from the source (Raga et al., 1990). Because of this, images
covering a wide field of view (FOV) around the suspected driving source are
essential to explore the mass ejection history. HH-jets interact with the
natal molecular cloud as they travel outwards entraining ambient material and
giving rise to large-scale molecular outflows (see e.g., reviews from Frank et
al. (2014) and Bally (2016) for a more complete picture of protostellar
outflow theory and observations).

We carried out a project aimed at obtaining new deep optical, narrow-band ([S
ii] and H$\alpha$) images of a sample of IRAS sources, candidates to be
tracing YSOs. A sample of fifteen targets was selected to be imaged in a
homogeneous way, covering a wide field of view ($\sim 15^{\prime}$) around the
IRAS counterpart, looking for shocked emission that could be associated with
the target. In addition to the narrow-band images, an image through an
off-H$\alpha$ filter was obtained to get the continuum emission, with the aim
of distinguishing between reflected and shocked emission in the neighborhood
of each of the sources. Because of the properties of the sources selected, we
expected to find HH jets with different evolutionary ages and spatial scales.
Most of the fields were not previously imaged through narrow-band filters, nor
with a several arcmin wide FOV. Such a spatial coverage is useful to explore
whether the HH jet shows discontinuities in its spatial emission, indicative
of episodic mass ejections. It was expected that the sample likely included
TTauri and Herbig Ae/Be stars being still actively accreting matter from
circumstellar disks and driving small scale jets, so that a product of the
project would be increasing the sample of known low-mass (TTauri) and
intermediate-mass (Herbig Ae/Be) sources driving HH jets. In this work, in
addition to the characterization of the optical emission associated with the
YSOs traced by the IRAS sources, we updated the observational data available
from optical and near-IR data archives for the targets observed, and we
performed new accurate astrometry of the jet knots and sources mapped in the
observed fields.

The work is structured as follow: in §2 we present the criteria followed to
select the sample to be observed; in §3 we describe the observations and data
reduction; in §4 we present an updated description of the data available and
the results obtained for each of the observed fields, and in §5 we summarize
the global results derived from our survey.

##  2 Sample selection criteria

The sample observed was extracted from the GLMP catalogues (García-Lario,
1991; García-Lario et al., 1997) and the optical survey of Suárez et al.
(2006) of nearby IRAS sources. GLMP uses the $[12]-[25]$ versus $[25]-[60]$
color–color (CC) diagram to identify YSO candidates. Later on Suárez et al.
(2006) confirm the YSO nature of several YSO candidates of the GLMP sample,
based on the optical spectrum of their IRAS counterpart, their luminosity
class, and their location in a star-forming region. We selected targets from
the GLMP catalogues and the Suárez et al. (2006) survey that, in addition,
showed optical emission in the DSS plates. As can be seen in Figures 1 and 2,
all of the selected targets have infrared (IR) color indices characteristic of
YSOs. Some of the targets are likely to be TTauri or Herbig Ae/Be, which would
be visible because they had already emerged from their native environment.
Thus, they would still be actively accreting matter from circumstellar disks
and could be driving small-scale jets (microjets). The resulting sample
consists of fifteen targets that were observable from the Calar Alto
Observatory (CAHA) in an observing run during the winter period. Table 1 lists
the sample of fields mapped.

Table 1: Observed sample

| $\alpha_{2000}$ | $\delta_{2000}$ |  |  |  |  |  | Distance
---|---|---|---|---|---|---|---|---
IRAS source | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$) | Counterpart | Classif.aa$a$b: binary; CI: Class I; FUO: FU Ori; HAeBe: Herbig Ae/Be; TT: TTauri; v: variable. | Associationbb$b$c: star cluster; n: extended nebular object. | HH in FOV | Location | (pc) | Ref.
I: Sources associated with jet emission |  |  |  |
00087+5833 | 00 11 26.5 |  $+58$ 49 50 | LkH$\alpha$ 198 | HAeBe | $\cdots$ | 161–164, 462 | L1265 | $\phantom{0}344\pm 17\phantom{0}$ | 1
02236+7224 | 02 28 16.4 |  $+72$ 37 36 | J02281661+7237328 | TT | RNO 7 (c) | 488 | L1340 | $\phantom{0}861\pm 22\phantom{0}$ | 2
03220+3035 | 03 25 09.2 |  $+30$ 46 21 | L1448-IRS1 | TT, b | RNO 13 (n) | 194–196 | L1448 | $\phantom{0}240\pm 12\phantom{0}$ | 1
04073+3800 | 04 10 41.2 |  $+38$ 07 54 | PP 13 | TT/FUO, b | PP 13 (n) | 463–465 | L1473 | $350$ | 3
04239+2436 | 04 26 55.3 |  $+24$ 43 34 | $\cdots$ | CI, b | $\cdots$ | 300 | Taurus | $129.0\pm 0.8\phantom{0}$ | 4
05380$-$0728 | 05 40 27.7 |  $-07$ 27 28 | Re 50N | CI | $\cdots$ | 1121–1122 | L1641 | $460$ | 5
II: Sources with extended nebular emission |  |  |  |
00044+6521 | 00 07 03.5 |  $+65$ 38 41 | PP 1, McC H12 | HAeBe | $\cdots$ | $\cdots$ | Cepheus IV | $\phantom{0}845\pm 110$ | 6
05302$-$0537 | 05 32 41.7 |  $-05$ 35 48 | J05324165$-$0535461 | CI, b | $\cdots$ | $\cdots$ | Orion A | $\phantom{0}319\pm 12\phantom{0}$ | 2
05393+2235 | 05 42 21.3 |  $+22$ 36 47 | J05422123+2236471 | FUO | RNO 54 (n) | $\cdots$ | $\cdots$ | $1540\pm 106$ | 2
06249$-$1007 | 06 27 18.1 |  $-10$ 09 41 | J06271812$-$1009387 | TT | HHL 43 (n) | $\cdots$ | $\cdots$ | $\phantom{0}860\pm 70\phantom{0}$ | 7
06562$-$0337 | 06 58 44.4 |  $-03$ 41 12 | J06584435$-$0341099 | HAeBe | Iron-clad Nebula | $\cdots$ | $\cdots$ | $5650\pm 430$ | 7
III: Point-like sources |  |  |  |
00422+6131 | 00 45 09.9 |  $+61$ 47 57 | J00450982+61147574 | TT | $\cdots$ | $\cdots$ | $\cdots$ | $2400^{+920}_{-520}\phantom{0}\phantom{0}$ | 2
02181+6817 | 02 22 22.6 |  $+68$ 30 43 | CO Cas | HAeBe, v | $\cdots$ | $\cdots$ | $\cdots$ | $\phantom{0}664\pm 25\phantom{0}$ | 2
05426+0903 | 05 45 22.4 |  $+09$ 04 13 | FU Ori | FUO | $\cdots$ | $\cdots$ | $\cdots$ | $\phantom{0}416\pm 9\phantom{0}\phantom{0}$ | 2
06471$-$0329 | 06 49 40.4 |  $-03$ 32 51 | J06494021$-$0332523 | CI | $\cdots$ | $\cdots$ | G216$-$2.5 | $2110\pm 21\phantom{0}$ | 1

111

(1) Zucker et al. (2020); (2) Gaia Collaboration et al. (2018); (3) Cohen et
al. (1983); (4) Galli et al. (2019); (5) Cohen (1990); (6) MacConnell (1968);
(7) See text.

According to the nature and morphology of the emission detected in this work
(see §4), and the data available in the literature, the sample was separated
in three groups, which are indicated in Table 1 and used in Figs. 1 and 2. The
first group (I) included fields with extended, pure-line emission, suggestive
of being produced by shocked (jet) emission. The second group (II) included
IRAS targets associated with nebular, reflected emission. Finally the third
group (III) included IRAS targets showing a point-like emission and for which
no extended emission, shocked or reflected, was detected in the entire field
mapped around the IRAS source. Each observed field is identified with the name
of the central IRAS source (listed in column 1) on which the images were
centered and its catalogue position is given in columns 2–3. The following
columns list the most probably optical counterpart assigned to the IRAS source
in the available literature. The classification of the counterpart (Class I,
TTauri, FU Ori, Herbig Ae/Be), and the membership of a cluster or extended
nebular nature of the object is also indicated. The rest of columns list the
HH objects catalogued in the FOV mapped, the star-forming region where the
IRAS source is located, when known, and finally, the distance to the source.
Some of the distances have been updated in this work from Gaia data (Gaia
Collaboration et al., 2018), and from the improved method based on parallaxes
of high-mass star-forming regions of Reid et al. (2019).222
http://bessel.vlbi-astrometry.org/node/378, Parallax-Based Distance Calculator
V2

Figure 1:  Location of the IRAS sources observed in the
($[12]-[25],[25]-[60]$) color–color diagram. The blue lines mark the region of
young stellar objects, and the magenta lines that of ultra-compact H ii
regions. Circles correspond to the sources driving jets, squares correspond to
the sources with extended nebular emission and triangles correspond to the
point-like sources (see Table 1).

As already mentioned, the observed targets have IR colors that are
characteristic of YSOs. Figure 1 presents the IRAS ($[12]-[25],[25]-[60]$) CC
diagram of the IRAS sources of the sample. The region of the plane where YSOs
are located is delimited by the blue lines (Palla, 1990), and the region
delimited by the magenta lines corresponds to the location of ultra-compact H
ii regions (Wood & Churchwell, 1989), probably associated with YSOs too.
Figure 2 presents the ($J-H,H-K$) CC diagram of the assigned near-IR IRAS
counterpart, when known. The $J,H,K$ magnitudes are taken from the 2MASS
catalogue333 This publication makes use of data products from the Two Micron
All Sky Survey, which is a joint project of the University of Massachusetts
and the Infrared Processing and Analysis Center/California Institute of
Technology, funded by the National Aeronautics and Space Administration and
the National Science Foundation.

The region of the plane delimited by the blue square corresponds to the
location of TTauri stars (Meyer et al., 1997), the purple lines delimits the
region of Herbig Ae/Be (Manoj et al., 2006), and the magenta lines delimits
the region of the luminous Class I protostars (Lada & Adams, 1992).

Figure 2: Location of the IRAS sources counterparts in the ($J-H,H-K$)
color–color diagram. The blue lines mark the TTauri region, the purple lines
the region of the Herbig Ae/Be stars, and the magenta lines that of Class I
sources. The symbols are the same as in Fig. 1.

##  3 Observations and Data Reduction

Observations were carried out on November 2016 with the 2.2 m telescope in the
Calar Alto Observatory (CAHA) using the Calar Alto Faint Object Spectrograph
(CAFOS) in direct imaging mode. The instrument was equipped with a 2048
$\times$ 2048 CCD, giving a spatial scale of $0\aas@@fstack{\prime\prime}53$
pixel-1 and a field of view of $16^{\prime}$. Three narrow-band filters were
used: the line filters of H$\alpha$ (central wavelength $\lambda=6569$ Å,
bandpass $\Delta\lambda=50$ Å), and [S ii] ($\lambda=6744$ Å,
$\Delta\lambda=97$ Å), which included the emission from the [S ii]
$\lambda=6717,6731$ Å lines, and an off-H$\alpha$ filter ($\lambda=6607$ Å,
$\Delta\lambda=43$ Å) to look for the continuum emission nearby to the
H$\alpha$ and [S ii] lines. Conditions were not photometric and the seeing
values varied from $1\aas@@fstack{\prime\prime}5$ up to $\sim
3^{\prime\prime}$ during the observing run.

Fourteen fields of our survey were mapped homogeneously in three narrow-band
filters, the H$\alpha$ and [S ii] lines and an off-line, nearby continuum
filter. One of the targets (IRAS 05302$-$0535) was only imaged through the [S
ii] filter due to problems during the runs. The images include a total of
eighteen IRAS sources. Three fields (centered on IRAS 02236+7224, 03220+3035
and 05380$-$0728) included a second IRAS source.

We obtained images in H$\alpha$ and [S ii] of 1 hr of total integration time
by combining three frames of 1200 s exposure each, and an additional continuum
image of 1200 s integration after combining two frames of 600 s exposure.

All the images were processed with the standard tasks of the IRAF444 IRAF is
distributed by the National Optical Astronomy Observatories, which are
operated by the Association of Universities for Research in Astronomy, Inc.,
under cooperative agreement with the National Science Foundation. reduction
package, which included bias subtraction and flatfielding corrections, using
sky flats. In order to correct for the misalignment between individual
exposures, the frames were recentered using the reference positions of field
stars well distributed around the source. Astrometric calibration of the
images was performed in order to compare the optical emission with the
positions of the objects reported in the field and, in particular, with the
nominal position of the IRAS sources. The images were registered using the
$(\alpha,\delta)$ coordinates from the USNO Catalogue555 The USNOFS Image and
Catalogue Archive is operated by the United States Naval Observatory,
Flagstaff Station. of ten field stars well distributed in the observed field.
The rms of the transformation was $0\aas@@fstack{\prime\prime}2$ in both
coordinates.

##  4 Results

In the following, we present the study carried out for each field, following
the classification of the sample in the three groups listed in Table 1. The
structure of each mapped field is as follows. First, we include a summary
updating the relevant information reported in the literature. Next, we detail
the new results found from our survey: (i) Wide field image in the narrow-
band, off-line continuum filter, with the IRAS source and other YSOs
potentially related to the source marked. (ii) Close-ups of selected regions
obtained from the images acquired through the H$\alpha$ and [S ii] line
filters. The sub-images allowed us to visualize and characterize the structure
of the extended emission around the IRAS source. (iii) For some targets we
also show close-ups from images retrieved from public data archives, with the
aim of comparing the emission in other wavelengths with the emission detected
in our observations. (iv) A table with the detailed astrometry of the shocked
emission, if detected. (v) In some cases, we propose a new identification of
the IRAS counterpart, based on updated catalogue information and in a more
accurate astrometry obtained from our images.

###  4.1 Group I: Sources associated with jet emission

####  4.1.1 IRAS 00087+5833

IRAS 00087+5833 is located in the dark cloud L1265, in Cassiopeia, at a
distance of $344\pm 17$ pc (Zucker et al., 2020). In the following we present
a short description of the field around the source.

Young stellar objects:

They are plotted in Fig. 3, a _Hubble Space Telescope_ (_HST_) image (_HST_
Legacy Archive. PI K. Stapelfeldt. Program ID: 8216. Cycle 8). Their positions
are given in Table 2. Namely:

V376 Cas:

Located north of IRAS. Classified as a Herbig Ae/Be star (Lagage et al.,
1993).

LkH$\alpha$ 198

(also known as V 633 Cas): Located south of IRAS. Classified as a Herbig Ae/Be
star (Aspin & Reipurth, 2000), and a spectroscopic binary Smith et al. (2005).

LkH$\alpha$ 198-IR:

Located $6^{\prime\prime}$ north of LkH$\alpha$ 198\. Classified as a deeply
embedded object. Has counterparts at 10 $\mu$m (Lagage et al., 1993) and 1.3
mm (Boissier et al., 2011).

LkH$\alpha$ 198-mm:

Located $\sim 19^{\prime\prime}$ northwest of LkH$\alpha$ 198\. Classified as
a deeply embedded object, with neither visible, nor IR emission detected. Has
counterparts at 1.3 mm (Henning et al., 1998) and 3 mm (Boissier et al.,
2011).

Proposed counterpart of IRAS:

LkH$\alpha$ 198, but it is offset $\sim 20^{\prime\prime}$ from the IRAS
position, outside the IRAS error ellipse, as are all the other YSOs.

Molecular outflows:

Several CO outflows, observed with low (Cantó et al., 1984) and high angular
resolution (Matthews et al., 2007), including:

  * •

Outflow with lobes east and west of LkH$\alpha$ 198, with signs of precession
(Smith et al., 2005) (LkH$\alpha$ 198 is a binary system).

  * •

Outflow in the north–south direction, centered on LkH$\alpha$ 198-mm (Smith et
al., 2005).

Optical outflows/Herbig-Haro objects:

Several knots in [S ii] near YSOs (Strom et al., 1986; Goodrich, 1993;
Corcoran et al., 1995; Aspin & Reipurth, 2000).

Identification of knots (Reipurth et al., 2000):

A and B:

correspond to HH 161, driven by LkH$\alpha$ 198-IR (Corcoran et al., 1995);

C, D, E, and F:

correspond to HH 164, driven by LkH$\alpha$ 198 (Corcoran et al., 1995);

G, H, I, and J:

correspond to HH 162.

HH 461:

a new HH, located $\sim 82^{\prime\prime}$ southeast of LkH$\alpha$ 198,
proposed to be a distant bow-shock of HH 164 (Aspin & Reipurth, 2000).

HHs 800-802:

proposed to be likely an extension of the LkH$\alpha$ 198 parsec-scale outflow
(McGroarty et al., 2004). They are outside the FOV of our images.

Figure 3:  IRAS 00087+5833: _HST_ WFPC2 image in the F814W filter of the field
around the IRAS source. The optical, near-IR and millimeter sources reported
in the field, and the IRAS position with the error ellipse are plotted. The
coordinates of these objects are given in Table 2. All figures are oriented
north up and east left.

Figure 4:  IRAS 00087+5833: CAHA image of the field in the continuum filter.

Figure 5:  IRAS 00087+5833: Close-up of the CAHA images in the H$\alpha$
(left) and [S ii] (right) filters. The YSOs are marked as in Fig. 4. The knots
HH 161A and HH 461 are enclosed in boxes.  Table 2: Young stellar objects
around IRAS 00087+5833

| Position |
---|---|---
| $\alpha_{2000}$ | $\delta_{2000}$ |
Source | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}})$ | (∘ $\arcmin$ $\arcsec$) | Ref.
V376 | 00 11 26.7 | +58 50 04 | 1
00087+5833 | 00 11 26.5 | +58 49 50 | 2
198-mm | 00 11 24.3 | +58 49 42 | 3
198-IR | 00 11 26.1 | +58 49 35 | 1
198 | 00 11 25.7 | +58 49 28 | 4
HH 161A | 00 11 27.4 | +58 49 26 | 5
HH 461 | 00 11 30.6 | +58 48 16 | 4, 5

(1) Lagage et al. (1993); (2) IRAS PSC; (3) Sandelll & Weintraub (1994); (4)
Aspin & Reipurth (2000); (5) This work.

Figure 4 displays the field around IRAS 00087+5833 mapped through the
continuum filter in our survey. We did not detect any new extended line
emission in H$\alpha$ nor in [S ii] in the field mapped. The YSOs around the
IRAS source, marked in the figure, lie all of them outside the IRAS position
error ellipse. This discards that any of these YSOs could be the counterpart
of IRAS 00087+5833. Figure 5 shows a close-up of the H$\alpha$ and [S ii]
images showing the extended emission associated with the YSOs. We detected
line emission from the HH knots HH 161A and HH 461. We did not find any
evidence of being related to the IRAS source. Regarding HH 461, the emission
of the knot is stronger in H$\alpha$ than in [S ii], which is a characteristic
of the emission from bow shocks. This confirms the nature of HH 461 as a bow
shock previously proposed by Aspin & Reipurth (2000), based only on
geometrical arguments.

####  4.1.2 IRAS 02236+7224

IRAS 02236+7224 is located in the dark cloud L1340, at a distance of $861\pm
22$ pc (Gaia Collaboration et al., 2018). In the following we present a short
description of the field around source.

Other IRAS sources in the field:

IRAS 02238+7222, in the southern part of the field, with colors that do not
correspond to a YSO. Does not seem related to the HHs of the field.

Young stellar objects:

The RNO~7 cluster of YSOs, with several low and intermediate-mass YSOs
surrounded by nebular emission.

Proposed counterpart of IRAS 02236+7224:

A low-mass, H$\alpha$-emission star (Kun et al., 2016a)

Optical outflows/Herbig-Haro objects:

Near IRAS 02236+7224:

Jet in H$\alpha$ and [S ii] emerging southwards from IRAS (Nanda Kumar et al.,
2002). Knots of the jet (Magakian et al., 2003):

HH 671A and B:

most probably associated with the cluster, but not clearly related to IRAS.

Knot 3:

located $\sim 1^{\prime}$ southwest of HH 671B, close to a bright H$\alpha$
emission star.

Knot 5:

HH 672 in the Reipurth et al. (2000) catalogue, located $\sim 3^{\prime}$
southwest of IRAS.

HH 488:

Chain of emission knots, in the east–west direction, south of IRAS 02238+7222,
observed in [S ii].

  * •

Exciting source not established up to now.

  * •

Different nomenclatures of the knots, as reported by Nanda Kumar et al.
(2002), Magakian et al. (2003), and in the Reipurth et al. (2000) catalogue
(see Table 3 for the cross-identifications based on the astrometry of the
present work).

  * •

IR counterparts of HH 488 and J optical knots and new knots HH 488E to G
without optical counterpart from _Spitzer_ images (Kun et al., 2016b).

Near-IR counterparts (H2 2.12 $\mu$m line) catalogued by Walawender et al.
(2016) as MHO objects (see Table 3).

Figure 6:  IRAS 02236+7224: CAHA image of the field in the off-line filter.
Another IRAS source (IRAS 02238+7222) lies inside the field mapped.

Figure 7:  IRAS 02236+7224: Close-up of the CAHA images through the H$\alpha$
(left) and [S ii] (right) filters. showing the field around the RNO 7 cluster,
where the IRAS source is located. The position of the IRAS source and its
error ellipse are marked. The knots are enclosed in boxes.

Figure 8:  HH 488: Close-up of the CAHA images in the H$\alpha$ (top) and [S
ii] (bottom) filters of the chain of knots of HH 488, close to IRAS
02238+7222. The emission features identified are enclosed in boxes.

Figure 9:  IRAS 02236+7224: Two-color image composed from _Spitzer IRAC_ 5.8
$\mu$m (red) and 3.6 $\mu$m (green) images with a FOV including the two IRAS
sources and the HH 488 jet.  Table 3: Emission line features in the IRAS
02236+7224 field

| Position |  |  |
---|---|---|---|---
| $\alpha_{2000}$ | $\delta_{2000}$ | Other id. | Near-IR
Knot1 | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$) | (2) | (3) | MHO4
HH 671 |
A | 02 28 15.65 | +72 37 45.3 | A | 1 | 2932
B | 02 28 09.03 | +72 36 28.9 | B | 2 | 2930
RNO7 |
H | 02 28 20.32 | +72 37 41.6 | $\cdots$ | $\cdots$ | 2932B
I | 02 28 00.4 | +72 35 56 | $\cdots$ | 3 | 2928D
HH 672 |
A | 02 28 53.2 | +72 36 13 | $\cdots$ | 5 | 2936
HH 488 |
J1-2 | 02 27 59.63 | +72 35 57.7 | J1-2 | $\cdots$ | 2928B,C
A | 02 28 22.53 | +72 34 55.5 | A | 4a | 2928G
b | 02 28 30.01 | +72 34 36.6 | B | 4b | 2928J
B | 02 28 35.52 | +72 34 31.5 | $\cdots$ | $\cdots$ | 2928K
D | 02 28 38.56 | +72 34 28.9 | E | 4d | 2928L
C | 02 28 41.98 | +72 34 18.3 | C | 4c | 2928M
E | 02 28 52.98 | +72 34 12.5 | $\cdots$ | $\cdots$ | 2928N
F | 02 28 56.40 | +72 34 03.6 | $\cdots$ | $\cdots$ | 2928O
G | 02 29 06.51 | +72 34 08.1 | $\cdots$ | $\cdots$ | 2928P

(1) This work (see Figs. 7, 8, and 9); (2) Reipurth et al. (2000); Nanda Kumar
et al. (2002); (3) Magakian et al. (2003); (4) Walawender et al. (2016).

Figure 6 displays the image of the field around IRAS 02236+7224 mapped through
the continuum filter. The RNO 7 cluster can be seen at the center of the
image, and the location of the two IRAS sources are also marked.

Our narrow-band images allowed us to identify the optical knots HH 671A and B,
the chain of knots HH 488A to D, the J complex northwest of IRAS 02238+7222,
and the HH 672 knot, $\sim 3^{\prime}$ southeast of IRAS02236+7224. In
addition, we detected a new knot $\sim 20^{\prime\prime}$ west of HH 671A,
labelled H in our images, which corresponds to the optical counterpart of MHO
2932B.

Figure 7 shows a close-up of the field around the RNO 7 cluster of our
H$\alpha$ and [S ii] images. HH 671A and B are detected in both lines, while
knot H is only detected in H$\alpha$, and knot I only in [S ii]. Based on
geometrical arguments, its is not clear whether all these knots form part of a
single stellar jet powered by IRAS 02236+7224. Most probably HH 671A and knot
H are tracing shocked emission produced by the stellar wind ejected from any
of the YSOs of the cluster, at some places of the nebulosity surrounding the
cluster.

Figure 8 shows a close-up of the H$\alpha$ and [S ii] images of the southern
part of the field around IRAS 02238+7222. They show the HH 672A knot,
northwest of IRAS 02238+7222, the curved string of emission features lying
from west to east, south of the IRAS source (HH 488), and the feature $\sim
2^{\prime}$ northwest of HH 488A labeled J1-2 in Fig. 8.

Regarding the cross-identification of the optical and near-IR knots of HH 488,
and the J complex, we show in Fig. 9 the color-composed image from the
_Spitzer_ archive, where these knots have been marked with the labels listed
in the first column of Table 3.

We made accurate astrometry of all the knots detected in our images, necessary
to determine the positions of the jet knots and the relationship between the
optical and near-IR knot emissions in a consistent way, including the MHOs
features reported by Walawender et al. (2016). Table 3 lists the positions for
all the HHs knots mentioned here. Since we found discrepancies in the
identifications of several knots of the field, the table displays the knots
identification of Nanda Kumar et al. (2002) and Magakian et al. (2003), and
the identification in the Reipurth et al. (2000) catalogue. The table also
displays the H2 MHO counterpart of each knot (Walawender et al., 2016).

Figure 10:  IRAS 03220+3035: CAHA image in the continuum filter of the field.
Another IRAS source (IRAS 03222+3034) lies inside the field mapped. The
positions and error ellipses of the IRAS sources are marked.

Figure 11:  IRAS 03220+3035: Close-up of the CAHA image through the H$\alpha$
filter _(top)_ and [S ii] filter _(bottom)_ , showing the field around the
IRAS source. The HH objects detected (194, 195, 196) are identified _(top)_ ,
and the knots listed in Table 4 are labeled, enclosed in boxes _(bottom)_.

####  4.1.3 IRAS 03220+3035

Table 4: HH knot positions of the IRAS 03220+3035 field | Position
---|---
| $\alpha_{2000}$ | $\delta_{2000}$
Knot | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$)
HH 194
A | 03 24 58.0 | +30 47 41
B | 03 24 56.9 | +30 47 41
C | 03 24 55.9 | +30 47 41
D | 03 24 51.0 | +30 48 20
HH 195
A | 03 25 14.4 | +30 48 49
B | 03 25 15.1 | +30 46 51
C | 03 25 14.7 | +30 46 58
D | 03 25 14.0 | +30 47 00
E | 03 25 13.2 | +30 47 16
F | 03 25 11.7 | +30 47 37
HH 196
A1 | 03 25 14.7 | +30 49 05
A2 | 03 25 14.6 | +30 49 07
A3 | 03 25 14.4 | +30 49 10
B1 | 03 25 13.2 | +30 49 15
B2 | 03 25 12.9 | +30 49 20
B3 | 03 25 12.7 | +30 49 24
C | 03 25 13.0 | +30 49 36
D | 03 25 25.8 | +30 46 56

IRAS 03220+3035 is located in L1448, in the Perseus cloud complex, at a
distance of $240\pm 12$ pc (Zucker et al., 2020). In the following we present
a short description of the field around the source.

Proposed association of IRAS with other objects:

RNO~13:

Red reflection nebula (Cohen, 1980), and

L1448~IRS1:

IR source (Hodapp, 1994).

Other IRAS in the region:

IRAS 03222+3034,

southeast of IRAS 03220+3035.

  * •

Associated with L1448 IRS2.

  * •

Very embedded, with no optical nor near-IR counterpart.

  * •

Classified as a Class 0 protostar, from far-IR and submillimeter data
(O’Linger et al., 1999).

IRAS 03225+3034 IRS3,

associated with YSOs (Anglada et al., 1989), but outside the field mapped.

Binarity:

L1448 IRS1 is a close ($1\aas@@fstack{\prime\prime}37$) binary system ($L$
band images of Connelley et al., 2008). Characteristics of each component from
near-IR spectroscopy (Connelley & Greene, 2010):

  * •

Northern component: line emission characteristic of a cavity or a young
stellar jet very close to the exciting source.

  * •

Southern component: line emission compatible with a weak TTauri star, thus in
an older evolutionary stage than the northern component.

Molecular outflows:

Low-velocity CO outflow, with blueshifted emission east of the source
(Levreault, 1988).

Optical outflows/Herbig-Haro objects:

HH 194:

H$\alpha$+[S ii] emission (Bally et al., 1997).

HH 195,

HH 196: H$\alpha$+[S ii] (Bally et al., 1997) and H${}_{2}\ \upsilon=1$–0 S(1)
emission (Eislöffel, 2000).

Figure 10 shows the wide field mapped in the continuum filter. The location of
the IRAS sources included in the field are marked. Figure 11 is a close-up of
the field mapped through the H$\alpha$ and [S ii] narrow-band filters. The
images show the location of HH 194, HH 195, and HH 196 (H$\alpha$ image), and
the knots identified in our [S ii] image, which have been labeled beginning
with A, the knot closest to the proposed driving source.

None of these HH objects is aligned with IRAS 03222+3034 (our target), so
there is no clear geometric argument to associate the driving source of any of
the HH objects with the IRAS source.

Let us discuss each HH object in more detail.

HH 194:

Its knots are aligned along the northern edge of the east-west CO outflow
(Levreault, 1988), most probably powered by the IRAS source. Thus, HH 194 can
be tracing the cavity wall of the CO outflow and is probably driven by IRAS
03222+3034. We identified four knots (labeled A to D in the [S ii] image).
Three knots, A, B, and C, are nearly aligned in the east-west direction, have
at bow-shaped morphology with the apex pointing northwards, and are brighter
in H$\alpha$ than in [S ii]. In addition, there is an arc-like diffuse
emission beyond knot C, ending $\sim 1^{\prime}$ northwest of HH 194C in a
compact knot, D, brighter in [S ii] than in H$\alpha$, which probably forms
part of the same outflow.

HH 195:

Consists of a “V”-shaped string of knots located $\sim 1^{\prime}$ northeast
of IRAS 03220+3035, pointing toward IRAS 03222+3034 (see Fig. 11). It
coincides with the northern knots of the H${}_{2}\ \upsilon=1$–0 S(1) outflow
centered on IRAS 03222+3034 (Eislöffel, 2000). Thus, IRAS 03222+3034 is most
probably the driving source of HH 195. The HH 195 knots are brighter in [S ii]
than in H$\alpha$.

HH 196:

Consists of an arc-shaped string of knots $\sim 3^{\prime}$ northeast of IRAS
03220+3035, with the apex oriented toward IRAS 03225+3034, outside the FOV of
our images, which has been proposed as the driving source of the outflow
(Bally et al., 1997). Our images also show HH 196D, $\sim\leavevmode\nobreak\
3\aas@@fstack{\prime}2$ southeast of HH 196A, in the direction of its apex,
identified as a part of the same optical outflow (Bally et al., 1997), and
reported in the near-IR too (Eislöffel, 2000). Our images show that both HH
196A and B could be resolved into several compact substructures engulfed in
nebular emission. We labeled these knotty substructures by adding a number to
the letter identifying the knot.

Astrometry of the HHs 194, 195 and 196 knots, including the newly identified
substructures, is given in Table 4.

####  4.1.4 IRAS 04073+3800

IRAS 04073+3800 is located in the dark cloud L1473 in the Perseus complex, at
a distance of $\sim 350$ pc (Cohen et al., 1983). In the following we present
a short description of the field around the source.

Proposed association of IRAS with other objects:

PP~13, an optical red nebula with a position closely matching that of IRAS
(Parsamian & Petrossian, 1979).

Young stellar objects:

The PP 13 nebula consists of two pre-main-sequence stars, classified from
optical, near-IR and submillimeter data (Aspin & Sandell, 2001):

PP 13N,

a TTauri star,

PP 13S,

a variable FU Ori star, also detected at 2.2 $\mu$m (Connelley et al., 2007).

Optical outflows/Herbig-Haro objects:

Three chains of HH objects around IRAS 04073+3800 (Aspin & Reipurth, 2000),
also detected at 2.2 $\mu$m (Connelley et al., 2007):

HH 463:

a cometary-like emission $\sim 10\arcsec$ long, arising from PP 13S
southwestward, with five [S ii] knots (A to E), plus a compact isolated [S ii]
emission at $\sim 1^{\prime}$ in the direction of the jet axis

HH 464:

a chain of five knots (A to E) along a curved path in the north–south
direction, beginning east of PP 13S and pointing toward the PP 13N tail.

HH 465:

an isolated knot north of PP 13N.

HH 464 and HH 465 form a bipolar jet driven by PP 13N (Aspin & Reipurth,
2000).

Figure 12:  IRAS 04073+3800: CAHA image through the continuum filter. The IRAS
source position and its error ellipse are shown. The positions of the
reflection nebulae PP 13N and S have been marked with white “$\times$”.

Figure 13:  IRAS 04073+3800: Close-up of the CAHA image through the H$\alpha$
filter _(top)_ and [S ii] filter _(bottom)_ , showing the field around the
IRAS source. The HH objects detected (463, 464, 465) are identified _(top)_ ,
and the knots listed in Table 5 are labeled _(bottom)_. The positions of the
two red nebulous objects (PP 13N and S) are marked as in Fig. 12.

Figure 14:  IRAS 04073+3800: _HST_ image of the field. The position of the IRAS source and its error ellipse are marked. The positions of the reflection nebulae PP 13N and S are marked with a “$\times$”.  Table 5: HH objects in the IRAS 04073+3800 field | Position
---|---
| $\alpha_{2000}$ | $\delta_{2000}$
Knot | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$)
HH 463
A | 04 10 41.1 | +38 07 53
B | 04 10 40.8 | +38 07 51
C/D | 04 10 40.7 | +38 07 47
E | 04 10 40.5 | +38 07 45
X1 | 04 10 37.7 | +38 07 00
X2 | 04 10 37.3 | +38 06 59
Y | 04 10 36.5 | +38 06 46
HH 464
A | 04 10 42.2 | +38 07 51
B | 04 10 42.3 | +38 07 44
C | 04 10 42.4 | +38 07 39
D | 04 10 42.0 | +38 07 29
E | 04 10 41.7 | +38 07 22
F | 04 10 40.7 | +38 06 58
HH 465
A | 04 10 42.5 | +38 08 34
Table 6: _HST_ knots in the IRAS 04073+3800 field | Position |
---|---|---
| $\alpha_{2000}$ | $\delta_{2000}$ |
Knot | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$) | Identif.
N1 | 04 10 41.69 | +38 08 06.7 |
N2 | 04 10 41.63 | +38 08 05.4 |
N3 | 04 10 41.57 | +38 08 04.1 |
S1 | 04 10 41.02 | +38 07 53.2 | HH 463A
S2 | 04 10 40.92 | +38 07 51.4 | HH 463B
S3 | 04 10 40.83 | +38 07 50.3 | HH 463B

Fig. 12 displays the image of the IRAS 04073+3800 mapped through the continuum
filter, where the location of the red nebulae and the IRAS source are marked.
As can be seen in the figure, PP 13S is most probably the counterpart of IRAS
04073+3800 because their positions are nearly coincident, while PP 13N does
not seem to be related to the IRAS source because it lies outside its error
ellipse.

A close-up of the field through the H$\alpha$ and [S ii] line filters is shown
in Fig. 13. The three HH jets (HH 463, 464, 465) are identified in the
H$\alpha$ image. Several knots have been identified in the jets and are
labeled in the [S ii] image according to previous [S ii] observations of Aspin
& Reipurth (2000). The astrometry of the knots of the [S ii] image is given in
Table 5. As can be seen in Fig. 13, most of the knots are brighter in [S ii]
than in H$\alpha$. The exceptions are knot A of HH 464, the knot closest to
the exciting source, and the line emission features X1/2 and Y, associated
with HH 463, which are brighter in H$\alpha$ than in [S ii]. In the case of HH
463X1/2 and Y, their position far away from the exciting source and their
disordered morphology suggest that they may be tracing bow shocks from older
mass-ejection episodes.

The field close to IRAS 04073+3800 was imaged by the _HST_ with the WPC2
camera through the F814W filter (PI D. Padgett. Program ID 9160. Cycle 10) and
with the NIC2 camera through the filter F110W, F160W and F205W (PI D. Padgett.
Program ID 10603. Cycle 14). Figure 14 shows a close-up of the F814W image.

We identified three knotty structures (N1, N2, N3) south of PP 13N at a
$\mathrm{PA}\simeq 25\degr$, and another three knots (S1, S2, S3) south of PP
13S at a $\mathrm{PA}\simeq 35\degr$. The astrometry of these knots, derived
from the _HST_ image, is given in Table 6. The S knots are part of the HH 463
jet. Given their positions, we could identify S1 with HH 463A, while S2 and S3
correspond to HH 463B, resolved in different substructures because of the
better resolution of the _HST_ image.

Regarding the N knots, they are well aligned with HH 465A ($\mathrm{PA}\simeq
20\degr$), so they could be part of the jet/counterjet system powered by PP
13N. However, they are also aligned with the S knots of the HH 463 jet, which
shows a curved morphology at large scales. Thus, they could also trace the
counterjet of HH 463, projected onto the PP 13N nebula.

Figure 15:  IRAS 04239+2436: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 16:  IRAS 04239+2436: Close-up of the CAHA image through the H$\alpha$
filter _(Top)_ and through the [S ii] filter _(Bottom)_.

####  4.1.5 IRAS 04239+2436

IRAS 04239+2436 is located in the B18 cloud of Taurus, at a distance of
$129.0\pm 0.8$ pc (Galli et al., 2019). In the following we present a short
description of the field around the source.

Classification:

Low-luminosity Class I protostar, from its near-IR spectrum (Greene & Lada,
1996).

Binarity:

Close binary (separation $0\aas@@fstack{\prime\prime}3$, 42 au in projection)
(Reipurth, 2000).

Molecular outflows:

CO outflow driven by IRAS (Moriarty-Schieven et al., 1992).

Optical outflows/Herbig-Haro objects:

Giant HH bipolar outflow HH 300 (Reipurth et al., 1997), driven by IRAS.

HH 300A, B and C:

redshifted, bright H$\alpha$+[S ii] knots with a bow-shock morphology, $\sim
30^{\prime}$ southwest of IRAS.

HH 300D:

blueshifted, compact and fainter knot, $\sim 30^{\prime\prime}$ northeast of
IRAS.

Near-IR emission:

  * •

Cometary nebula surrounding the system (_HST_ (NICMOS F160W and F205W;
Reipurth, 2000)

  * •

Jet emission in [Fe ii] collimated and bipolar (Davis et al., 2011), with axis
coincident with the optical HH 300A–C knots axis (Reipurth, 2000).

  * •

Jet emission in H2 collimated and bipolar (Davis et al., 2011).

  * •

Jet emission in Br$\gamma$ isotropical (Davis et al., 2011).

Table 7: HH 300 knots in the IRAS 04239+2626 field | Position
---|---
HH 300 | $\alpha_{2000}$ | $\delta_{2000}$
Knot | (${}^{\mathrm{h\leavevmode\nobreak\ m\leavevmode\nobreak\ s}}$) | (∘ $\arcmin$ $\arcsec$)
D1 | 04 26 53.4 | +24 43 12
D | 04 26 59.2 | +24 43 59
DE | 04 26 59.1 | +24 43 58
DW | 04 26 58.6 | +24 43 59
D0 | 04 26 57.9 | +24 43 42

The field of our images centered on IRAS 04239+2436 did not include the bright
redshifted HH 300A, B and C knots. Figure 15 shows the field imaged in the
continuum filter with the location of the IRAS source. Figure 16 shows a
close-up of the field surrounding IRAS 04239+2436 through the H$\alpha$ and [S
ii] line filters. As can be seen in the figure we detected emission in the two
lines from two knots of the blueshifted HH 300 jet. In the H$\alpha$+[S ii]
image of Reipurth et al. (1997), HH 300D shows a conical shape, reminiscent of
a bow-shock. Our images revealed that the morphology of knot D changes from
H$\alpha$ to [S ii]. In the H$\alpha$ line, knot D shows the bow-shock shape
reported before, while in the [S ii] line knot D appears split in two (labeled
DE and DW in our [S ii] image): knot DE coincides with the apex of the
H$\alpha$ emission of knot D; and knot DW coincides with the northern tip of
knot D. A new knot, D0, $\sim 15^{\prime\prime}$ northeast of the IRAS
position was found in the two lines. Finally, we found knotty, faint H$\alpha$
emission without [S ii] counterpart $\sim 55^{\prime\prime}$ southwest of the
IRAS position (labeled D1) most probably corresponding to the redshifted jet
component. We made astrometry of the knots from our images and their positions
are given in Table 7.

Figure 17:  IRAS 05380$-$0728: CAHA image through the continuum filter. The
IRAS source position and error ellipse are shown. The positions of the other
IRAS source and the Red Nebulous Objects in the field are also shown.

Figure 18:  IRAS 05380$-$0728: Close-up of the CAHA image through the
H$\alpha$ _(top)_ and [S ii] _(bottom)_ filters. The positions of the Red
Nebulous Objects are marked with white “$\times$”, and that of the IRAS
sources with red “+”. Black rectangles mark the locations of the emission line
features reported in the field.

####  4.1.6 IRAS 05380$-$0728

IRAS 05380$-$0728 is located in the southern region of the L1641 molecular
cloud, at a distance of 460 pc (Cohen, 1990). In the following we present a
short description of the field around the source.

Luminosity:

One of the most luminous objects of the cloud. Estimated total luminosity of
250 $L_{\odot}$ (Reipurth & Bally, 1986).

Association of IRAS with other objects:

IRS1, in the western edge of the reflection nebula Re50N, a very red point-
like source (Casali, 1991).

  * •

Detected in the near-IR ($J$, $H$, $K$, $L$ bands).

  * •

Coinciding with the IRAS position.

Reflection nebulae:

Re50S and Re50N (Reipurth, 1985).

  * •

Associated with YSOs.

  * •

Extended emission.

  * •

Variability: from 2006 to 2014, Re50N increased its brightness while Re50S
faded significantly, probably caused by dusty material orbiting the sources
(Chiang et al., 2015).

Optical outflows/Herbig-Haro objects:

SMZ9-4, 5 and 6:

a large-scale strand of knots and filaments in the H2 line at 2.12 $\mu$m
(Stanke et al., 2000). Driven by a different source, IRAS 05380-0731.

HH 65:

faint, single knot in [S ii] (Reipurth & Graham, 1988), located at the red
lobe of a bipolar CO outflow. It is the optical counterpart of SMZ9-6.

HH 1121:

a knotty chain north of the Re50S nebulosity (Chiang et al., 2015).

HH 1122:

two faint knots $\sim 1^{\prime}$ southwest of Re50S (Chiang et al., 2015).

Fig. 17 displays the field centered on IRAS 05380$-$0728 imaged trough the
continuum filter. Another IRAS source, IRAS 05380-0729, appears also in the
image. IRAS 05380$-$0728 is located at the tip of Re50N. In our image, both
Re50N and Re50S appear with a similar brightness. Re50N has an ‘S’ shape,
while Re50S has an arrowhead shape. The same morphology is found in the
H$\alpha$ and [S ii] filter images (Fig. 18).

Regarding the variability of Re50N and Re50S, both nebulosities keep the same
shape as observed in the [S ii] image of 2014 (Chiang et al., 2015). However,
in our [S ii] image (Fig. 18) Re50N and Re50S have a similar brightness, and
Re50S is not dimmer than Re50N as reported in 2014 (Chiang et al., 2015).
Concerning the HH objects of the region, we detected HH 65 in the H$\alpha$
and [S ii] images. We found a slightly different morphology in H$\alpha$ and
[S ii]: the knot is more compact and brighter in [S ii] than in H$\alpha$. HH
1121 was only detected in the [S ii] image. In contrast, HH 1122 was detected
in both emission lines, being brighter in H$\alpha$ than in [S ii]. We did not
detect any additional emission line features in our deep narrow-band images of
this region.

Figure 19:  IRAS 00044+6521: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 20:  IRAS 00044+6521: Close-up of the CAHA images through the H$\alpha$
_(top)_ and [S ii] _(bottom)_ filters.

Figure 21:  IRAS 00044+6521: _HST_ ACS/WFC image through the F814W filter of
the field around the IRAS source. The white ‘’+” marks the position of the
2MASS source J00070260+6538381. The IRAS position and its error ellipse are
also shown.

###  4.2 Group II: Sources associated with extended nebular emission

####  4.2.1 IRAS 00044+6521

IRAS 00044+6521 belongs to the Cepheus IV association, at a distance of
$845\pm 110$ pc (MacConnell, 1968). In the following we present a short
description of the source.

Proposed IRAS counterpart:

  * •

The optical object appears as a Herbig Ae/Be of the Herbig & Bell (1988)
catalogue as HBC~1.

  * •

Also known as the emission star MacC H12 (MacConnell, 1968), with H$\alpha$
line emission (Cohen & Kuhi, 1976).

  * •

Included in the Herbig Ae/Be survey of Thé et al. (1994), and classified with
a spectral type around F4 (Hernández et al., 2004).

  * •

Broad-band ($R$, $I$, $J$, $H$, $K$, $L$) images (Origlia et al., 1990) show a
red stellar component and a nebula, consistent with a TTauri star with an
accretion disk and a cold dust envelope.

  * •

Its position is offset $\sim 5^{\prime\prime}$ from the IRAS position.

Figure 19 shows the image of the field around IRAS 00044+6521 through the
continuum filter, and Fig. 20 shows close-ups of the H$\alpha$ and [S ii]
lines filter images.

As can be seen in the figures, the target shows a compact emission, inside the
position error ellipse of IRAS 00044+6521, plus a cometary tail $\sim
10^{\prime\prime}$ long, extending southeastward. The extended emission has
the same shape in continuum and line emission, thus confirming that the origin
of the emission is most probably scattered light, and not shock excitation
from a stellar microjet. We measured an offset of
$6\aas@@fstack{\prime\prime}5$ between the nominal position of the IRAS source
and the 2MASS source J00070260+6538381, the 2MASS source coinciding with the
photocenter of the compact optical counterpart.

Figure 21 shows a close-up of the field around IRAS 00044+6521 from the _HST_
ACS/WFC image through the F814W filter, extracted from the _HST_ Legacy
Archive (PI Sahai. Program ID: 10536). The extended emission can be seen in
more detail, showing an arc-shaped morphology, with its center toward the IRAS
position. The proposed optical/near-IR counterpart of IRAS lies at the
northwest tip of the nebulosity.

Figure 22:  IRAS 05302$-$0537: CAHA image in the narrow-band [S ii] filter.
The IRAS source position and error ellipse are shown in black. Haro 4-145 is
marked with a white “+”. The IR source Vision J5324165$-$0535461 (Meingast et
al., 2016) is marked with a red “+”, nearly overlapping the black “+” of the
IRAS source.

####  4.2.2 IRAS 05302$-$0537

IRAS 05302$-$0537 is located at the southern part of Orion A, at a distance of
$319\pm 17$ pc (Gaia Collaboration et al., 2018). In the following we present
a short description of the field around the source.

First proposed counterpart of IRAS:

Haro~4-145, an H$\alpha$ emission star (Parsamian & Chavira, 1982).

Present proposed counterpart of IRAS:

$K$-band reflection nebula:

point-like counterpart with a diffuse nebula extending northwards from the
near-IR source (Connelley et al., 2007).

J05324165-0535461:

Near-IR source (Orion A VISTA catalogue; Meingast et al., 2016), with position
coincident with IRAS. Source slightly elongated in the northeast–southwest
direction (consistent with its binary nature, see below), surrounded by
diffuse, arc-shaped emission extending from northwest to southeast of the
compact source.

Binarity:

Binary system with an angular separation of $0\aas@@fstack{\prime\prime}65$
($L$-band images; Connelley et al., 2008).

Tracers of YSOs:

  * •

Bipolar CO outflow (Orion A-west; Fukui et al., 1986).

  * •

High-density ammonia clump centered on IRAS (Harju et al., 1993).

Due to weather conditions, only the narrow-band [S ii] image of the IRAS
05302$-$0537 field was obtained in our CAHA survey (Fig. 22). We barely
detected a faint, compact emission coinciding with the IRAS source, but we did
not detect any extended emission associated with it. Our image also shows
another YSO, Haro 4-145. This object is in a more evolved stage than
J05324165-0535461, as indicated by its near-IR colors, and the lower
extinction allowing to be detected at optical wavelengths. Haro 4-145 lies
$\sim 25^{\prime\prime}$ southeast of the IRAS source position, outside the
IRAS error ellipse. Thus, it is unlikely to be the optical counterpart of the
IRAS source. Instead, J05324165-0535461 is more likely to be the IRAS
counterpart.

Figure 23:  IRAS 05393+2235: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 24:  IRAS 05393+2235: Close-up of the CAHA images through the H$\alpha$
_(top)_ and [S ii] _(bottom)_ filters.

####  4.2.3 IRAS 05393+2235

IRAS 05393+223 is located at a distance of $1540\pm 106$ pc (Gaia
Collaboration et al., 2018). In the following we present a short description
of the source.

IRAS counterpart:

RNO~54, a red nebulous object (Cohen, 1980).

  * •

Associated with extended emission (Cohen, 1980) with a cometary-shape
morphology (broad-band, $R$ filter image; Goodrich, 1987),

  * •

FU Ori star, with a spectral type F5 II (Goodrich, 1987).

  * •

Probable post-FU Ori star (double Li absorption profile; Torres et al., 1995).

Figure 23 shows the IRAS 05393+2235 field in the continuum filter and Figure
24 shows close-ups in the H$\alpha$ and [S ii] line filters. As can be seen in
the figures, the extended, arc-shaped nebulosity surrounding the compact
counterpart of the IRAS source presents the same morphology in the continuum
and in the line images, indicating that the extended emission is most probably
a reflection nebula. No evidence of shocked gas was found in our narrow-band
images.

Figure 25:  IRAS 06249$-$1007: CAHA image through the continuum filter. The
IRAS source position and error ellipse are shown.

Figure 26:  IRAS 06249$-$1007: Close-up of the CAHA image through the
H$\alpha$ _(top)_ and [S ii] _(bottom)_ filters showing the field centered on
the IRAS source The stars of the IR cluster reported by Tapia et al. (1997)
are marked with “+”.

####  4.2.4 IRAS 06249$-$1007

IRAS 06249$-$1007 is located at a kinematic distance of $0.86\pm 0.07$ kpc
(see Footnote 2), determined from its radial velocity, $V_{\mathrm{LSR}}=12.2$
km s-1 (Wilking et al., 1989). In the following we present a short description
of the field around the source.

Optical and IR emission:

  * •

IRAS located $\sim 10^{\prime\prime}$ from the southwest edge of the loop-
shaped nebula HHL~43 (Gyulbudaghian, 1984).

  * •

HHL 43 has the same loop-shaped morphology in broad-band optical ($I$) and
near-IR ($J$, $H$, $K$) images (Tapia et al., 1997).

  * •

Emission at 100 $\mu$m peaking at the nominal position of IRAS (Di Francesco
et al., 1998).

Young stellar objects:

  * •

A cluster of four stars, all inside the IRAS error ellipse, with near-IR
colors characteristic of embedded TTauri stars (Tapia et al., 1997).

  * •

The position of one of the stars (star 3) coincides with the IRAS position and
with the 2MASS source J06271812$-$1009387.

Molecular outflows:

A CO outflow toward the IRAS position, most probably driven by the source
(Wilking et al., 1989).

Figure 25 shows the image of IRAS 06249$-$1007 field through the continuum
filter. Close-ups of the narrow-band images in the H$\alpha$ and [S ii] line
filters are shown in Fig. 26. As can be seen in the figures, the nebula shows
the same morphology in continuum and in the line images, indicating that the
origin of the emission is mainly reflection (dust illuminated by the cluster
of stars), without signs of shocked emission. In our images, the cluster of
YSO including the IRAS counterpart lies outside the nebular emission. We did
not detect any optical counterpart of any of the YSO of the cluster. This is
consistent with an extinction increasing from north to south along the nebula
(Tapia et al., 1997), with the YSO cluster being embedded in extended $K$-band
emission.

Figure 27:  IRAS 06562$-$0337: CAHA image through the continuum filter. The
IRAS source position and error ellipse are shown. C

Figure 28:  IRAS 06562$-$0337: Close-up of the CAHA image through the
H$\alpha$ _(top)_ and [S ii] _(bottom)_ filters, showing the field centered on
the IRAS source. The positions of the IRAS source (white) and the $K$-band
star reported by Alves et al. (1998) (green) are marked with “+”.

####  4.2.5 IRAS 06562$-$0337

IRAS 06562$-$0337 is located at a kinematic distance of $5.65\pm 0.43$ kpc
(see Footnote 2), determined from its radial velocity,
$V_{\mathrm{LSR}}=54.0\pm 0.2$ km s-1 (Bachiller et al., 1998). In the
following we present a short description of the field around the source.

Controversial nature of IRAS:

  * •

Originally classified as a possible planetary nebula (PN) (MacConnell, 1978),
based on a spectrum showing the H$\alpha$ emission line and absence of
continuum emission.

  * •

Renamed as Iron-clad Nebula, and classified to be in a transition phase from
AGB to PN, based on its high variability and spectrum dominated by allowed and
forbidden Fe ii lines (Kerber et al., 1996).

Association of IRAS with molecular gas:

CO, 13CO, and CS emission at millimeter and sub-millimeter wavelengths
(Bachiller et al., 1998).

  * •

Powering source of a molecular outflow traced by the high-velocity CO
emission.

  * •

Non-evolved object because the CS molecule is destroyed in the proto-PN stage.

Association of IRAS with IR emission:

$K^{\prime}$-band image of the field (Alves et al., 1998).

  * •

IRAS is a young, rich stellar cluster embedded in diffuse emission.

  * •

The cluster contains $\sim 70$ stars within a $30^{\prime\prime}$ radius
around the bright central object.

  * •

The central object is likely a Herbig Be star.

  * •

Spectral variability of the central object attributed to a stellar wind in its
extended atmosphere.

  * •

The coordinates of the central source in the $K^{\prime}$-band image are in
agreement with the CO emission peak.

Figure 27 shows the IRAS 06562$-$0337 field mapped through a continuum filter,
and Fig. 28 shows close-ups of the H$\alpha$ and [S ii] line filter images,
where the stars of the IR cluster have been marked. We did not detect any
nebular, shocked emission from jet structures.

Figure 29:  IRAS 00422+6131: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 30:  IRAS 00422+6131: Close-up of the CAHA image through the H$\alpha$
_(top)_ and [S ii] _(bottom)_ filters showing the field centered in IRAS
00422+6131.

###  4.3 Group III: Point-like sources

####  4.3.1 IRAS 00422+6131

IRAS 00422+6131 is located at a distance of $2400^{+920}_{-520}$ pc, derived
from its parallax (Gaia Collaboration et al., 2018). In the following we
present a short description of the field around the source.

Controversial nature of IRAS:

  * •

The source lies in projection toward the young open cluster NGC~225, although
it is not a member of it (Lattanzi et al., 1991).

  * •

First identified as a TTauri star on he basis of its IRAS colors (García-Lario
et al., 1997).

  * •

Later proposed to be a G giant star, based on its optical spectrum (Pereira &
Miranda, 2007).

Association of IRAS with IR emission:

2MASS $J$, $H$, $K$ images show extended emission surrounding the point-like
source J00450982+6147574.

Figure 29 shows the image of the IRAS 00422+6131 field through a continuum
filter. Close-ups of the narrow-band images in the H$\alpha$ and [S ii] line
filters are shown in Fig. 30.

All the images show a similar morphology of the IRAS optical counterpart. We
did not detect in our narrow-band line images any shocked emission from jet
structures.

Figure 31:  IRAS 02181+6817: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 32:  IRAS 02181+6817: Close-up of the CAHA image through the H$\alpha$
_(top)_ and [S ii] _(bottom)_ filters. The catalogue position of IRAS
02181+6817 is marked in black, the 2MASS source J02222276+6830471 in cyan, and
an additional point-like object in magenta.

####  4.3.2 IRAS 02181+6817

IRAS 02181+6817 is located at a distance of $664\pm 25$ pc (Gaia Collaboration
et al., 2018). In the following we present a short description of the source.

Proposed IRAS counterpart:

An optical/near-IR bright star.

  * •

Classified as a TTauri star, based on the IRAS colors (García-Lario, 1991).

  * •

Reported as a non-periodic variable star, CO Cas (Hoffmeister, 1936; Samus et
al., 2017), with an average $V_{\mathrm{mag}}=15.52$, and a variation
amplitude of 1.15 mag (Kochanek et al., 2017)666 htpps://asa-sn.osu.edu, ASAS-
SN Sky Patrol

  * •

Coincides with the 2MASS star J02222276+6830471, with near-IR colors
compatible with being a Herbig Ae/Be source.

  * •

The 3D dust maps of Green et al. (2019)777 http://argonaut.skymaps.info, 3D
Dust Mapping with Pan-STARRS 1, 2MASS and Gaia give an extinction in the $R$
band $A_{R}=0.93$ at the distance of the source.

Fig. 31 shows the image of the IRAS 02181+6817 field through a continuum
filter. Close-ups of the narrow-band images in the H$\alpha$ and [S ii] line
filters are shown in Fig. 32.

We found two sources located less than $5^{\prime\prime}$ from the IRAS
position, inside the IRAS error ellipse. The brighter source is CO Cas, the
proposed IRAS counterpart. The other source is located a few arcsec southeast
of CO Cas (labeled as 3 in Fig. 32). The source is faint and slightly
elongated in the northwest–southeast direction, and could be tracing a micro-
jet powered by CO Cas.

Figure 33:  IRAS 05426+0903: CAHA image through the continuum filter. The IRAS
source position and error ellipse are shown.

Figure 34:  IRAS 05426+0903: Close-up of the CAHA image through the H$\alpha$
_(top)_ and [S ii] _(bottom)_ filters.

####  4.3.3 IRAS 05426+0903

The optical counterpart of IRAS 05426+0903 is the prototypical, young pre-main
sequence star FU Ori. It is located at a distance of $416\pm 9$ pc (Gaia
Collaboration et al., 2018). In the following we present a short description
of the source.

Binarity:

  * •

The source is a binary system (Wang et al., 2004; Reipurth & Aspin, 2004).

  * •

The companion is a red star, FU Ori S, $\sim 0\aas@@fstack{\prime\prime}5$
south of FU Ori.

FU Ori characteristics:

  * •

Optically thick accretion disk (mid-IR, 8–13 $\mu$m interferometric
observations; Beck & Aspin, 2012).

  * •

Continuum emission at 1 mm detected from circumstellar disk (ALMA Band 7 with
$0\aas@@fstack{\prime\prime}6$ angular resolution; Hales et al., 2015).

FU Ori S characteristics:

  * •

Hints of a disk (mid-IR; Beck & Aspin, 2012).

  * •

FU Ori S is an actively accreting young star, with
$\dot{M}_{\mathrm{acc}}\simeq\mbox{(2--3)}\times 10^{-8}M_{\odot}$ yr-1, and
is the more massive component of the binary system (Beck & Aspin, 2012).

  * •

Continuum emission at 1 mm detected from circumstellar disk (Hales et al.,
2015).

  * •

High-density tracer HCO+ emission-peak close to FU Ori S, indicating that it
is embedded in dense molecular gas (Hales et al., 2015).

Circumbinary reflection nebula:

  * •

Detected through near-IR, high-resolution imaging polarimetry (Liu et al.,
2016; Takami et al., 2018).

  * •

Arc-like morphology, reminiscent of a spiral arm stretching from east to
northeast of the FU Ori system.

  * •

Morphology probably caused by gravitational instabilities in the accretion
disks, in an unstable phase of protoplanetary disk evolution.

Figure 33 shows the IRAS 05426+0903 field mapped through a continuum filter.
Close-ups of the narrow-band images in the H$\alpha$ and [S ii] line filters
are shown in Fig. 34. All the images show a similar morphology of the IRAS
optical counterpart. We did not detect shocked emission from jet structures in
our narrow-band line images.

Figure 35:  IRAS 06471$-$0329: CAHA image through the continuum filter. The
IRAS source position and error ellipse are shown.

Figure 36:  IRAS 06471$-$0329: Close-up of the CAHA image through the
H$\alpha$ _(top)_ and [S ii] _(bottom)_ filters. The positions from the Vizier
Catalogue of the IRAS source (white) and of the 2MASS source J06494021-0332523
(magenta) are marked.

####  4.3.4 IRAS 06471$-$0329

IRAS 06471$-$0329 is located near the CO boundary of G216$-$2.5, at a distance
of $2110\pm 21$ pc (Zucker et al., 2020). In the following we present a short
description of the source.

First proposed counterpart of IRAS:

A red star detected in the $I$-band (Campbell et al., 1989).

Later proposed counterpart of IRAS:

One of the two bright stars in the $K$-band, close to the IRAS position (Lee
et al., 1996).

  * •

Very high reddening, with near-IR colors consistent with those of embedded
YSOs.

  * •

Associated with an IR nebulosity (Ishii et al., 2002).

  * •

Absorption feature at 3.1 $\mu$m from H2O ice, usually present in high-density
interstellar clouds protected from UV radiation, characteristic of embedded
objects.

Figure 35 shows the image of the IRAS 06471$-$0329 field through a continuum
filter. Close-ups of the narrow-band images in the H$\alpha$ and [S ii] line
filters are shown in Fig. 36. We detected in all the images a weak nebular
emission surrounding three point-like sources southwest of the bright star at
the center of the field. This weak reflection nebula should correspond to the
near-IR emission detected by Lee et al. (1996) and Ishii et al. (2002). In the
narrow-band line images (Fig. 36) we show the catalogue positions of the IRAS
source (white) and the 2MASSX source J06494021$-$0332523 (red). As can be seen
in Fig. 36, the position of the 2MASSX source coincides with a weak star
surrounded by nebular emission. Thus, we concluded that the optical
counterpart of IRAS 06471$-$0329, instead of being the bright star at the
center of the field, is most probably the more embedded near-IR source
J06494021$-$0332523.

##  5 Conclusions

We obtained narrow-band images covering a wide FOV around a sample of IRAS
sources that were proposed to be associated with YSOs, based mainly on their
location in CC diagrams. The association of the IRAS source with young stellar
objects has been confirmed from the images obtained. Although these fields
were observed in the past, our survey provides new data both for the IRAS
counterparts themselves and for their environment. In particular:

  * •

In this survey, the first-ever images through the narrow-band, H$\alpha$ and
[S ii], line filters were obtained for nine IRAS sources (all the targets of
groups II and III). The IRAS sources of group II were known to have extended
emission. However, previous imaging was only made through broad-band filters,
which do not allow to distinguish with confidence between reflected and
shocked emission. The narrow-band images obtained confirm the nature of the
extended component of the emission associated with the targets. In IRAS
02181+6817, a point-like target of group III, an elongated emission in the
H$\alpha$ and [S ii] lines was detected, southeast of the source, which could
be tracing a micro-jet powered by the source.

  * •

New images in the two emission lines, H$\alpha$ and [S ii], were obtained for
three sources of group I (IRAS 03220+3035, 04073+3800, and 04239+2436) These
sources were previously mapped only in one of the lines, or through a broad-
band, red continuum filter.

  * •

In six of the mapped fields (group I), extended emission in the H$\alpha$ and
[S ii] lines was detected, with no continuum counterpart, tracing HH jets. In
some targets (IRAS 00087+5833, 02236+7224, and 03220+3034), the jet emission
was not associated with the IRAS target, but with another YSO in the mapped
field.

  * •

The astrometric positions of most of the jet knots were not reported in the
literature. Astrometry of the jet knots mapped in our images was performed,
and is given in the section corresponding to each source. In addition, new
substructures were resolved within the knots of the jets of HH 196A and HH
196B, imaged in the field of IRAS 03220+3035, and HH 300, powered by IRAS
04239+2436. Two new knotty emissions, closer to the IRAS source, labeled HH
300D0 and D1, were identified in the images.

  * •

For three of the observed fields (IRAS 00087+5833, 02236+7224, and 04073+3800)
we were able to identify jet knots in previous optical and near-IR images in
public archives (_HST_ , _Spitzer_). Their positions were compared with our
results from the CAHA observations, and near-IR counterparts of some knots
were identified.

  * •

We confirmed or proposed a different IRAS counterparts for seven targets of
the sample (IRAS 00044+6521, 00087+5833, 04073+3800, 05302$-$0537, 05393+2235,
06249$-$1007, and 06471$-$0329). To sustain these associations, the
astrometric positions of the YSOs in the neighborhood of the target source
were obtained.

###### Acknowledgements.

This work has been partially supported by the Spanish MINECO grants
AYA2014-57369-C3 and AYA2017-84390-C2 (cofunded with FEDER funds), and
MDM-2014-0369 of ICCUB (Unidad de Excelencia ‘María de Maeztu’). This research
has made use of the SIMBAD database, operated at CDS, Strasbourg, France.

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