#  The long-term spectral changes of eta Carinae: are they caused by a
dissipating occulter as indicated by cmfgen models?

Damineli, Augusto Universidade de São Paulo, Instituto de Astronomia,
Geofísica e Ciências Atmosféricas,
Rua do Matão 1226, Cidade Universitária, São Paulo, Brasil  Hillier, Desmond
J. Department of Physics and AstronomyFEii & Pittsburgh Particle Physics,
Astrophysics, and Cosmology Center (PITT PACC),
University of Pittsburgh, 3941 O’Hara Street, Pittsburgh, PA 15260, USA
Navarete, Felipe SOAR Telescope/NSF’s NOIRLab, Avda Juan Cisternas 1500,
1700000, La Serena, Chile  Moffat, Anthony F. J Département de Physique and
Centre de Recherche en Astrophysique du Québec (CRAQ)
Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, Québec, H3C
3J7, Canada  Weigelt, Gerd Max Planck Institute for Radio Astronomy, Auf dem
Hügel 69, D-53121 Bonn, Germany  Corcoran, Michael F. CRESST II & X-ray
Astrophysics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD
20771, USA  The Catholic University of America, 620 Michigan Avenue N.E.,
Washington, DC 20064, USA  Gull, Theodore. R. Exoplanets & Stellar
Astrophysics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD
20771, USA  Richardson, Noel D. Department of Physics and Astronomy, Embry-
Riddle Aeronautical University, 3700 Willow Creek Road, Prescott, AZ 86301,
USA  Ho, Peter  Department of Applied Mathematics, University of California,
Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, USA  Madura, Thomas I.
Department of Physics and Astronomy, San José State University, One Washington
Square, San José, CA 95192-0106, USA  Espinoza-Galeas, David Departamento de
Astronomia y Astrofisica, Facultad de Ciencias Espaciales, Universidad
Nacional Autonoma de Honduras, Bulevar Suyapa, TegucigalpFEiia, M.D.C,
Honduras, Centroamerica  Hartman, Henrik Materials Science and Applied
Mathematics, Malmö University, SE-20506 Malmö, Sweden  Morris, Patrick
California Institute of Technology, IPAC, M/C 100-22, Pasadena, CA 91125, USA
Pickett, Connor S  Department of Physics and Astronomy, Embry-Riddle
Aeronautical University, 3700 Willow Creek Road, Prescott, AZ 86301, USA
Stevens, Ian R. School of Physics & Astronomy, University of Birmingham,
Birmingham B15 2TT, UK  Russell, Christopher M. P. Department of Physics and
Astronomy, University of Delaware, Newark, DE 19716, USA  Hamaguchi, Kenji
CRESST II and X-ray Astrophysics Laboratory, NASA/Goddard Space Flight Center,
Greenbelt, MD 20771, USA  Department of Physics, University of Maryland
Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA  Jablonski,
Francisco J. Instituto Nacional de Pesquisas Espaciais/MCTIC Avenida dos
Astronautas 1758, São José dos Campos, SP, 12227-010, Brazil  Teodoro, Mairan
Space Telescope Science Institute, 3700 San Martin Dr, Baltimore, MD 21218
McGee, Padric  Department of Physics, School of Physical Sciences, University
of Adelaide, South Australia, 5005  SASER Team, 269 Domain Road, South Yarra,
Vic 3141, Australia  Cacella, Paulo  SASER Team, 269 Domain Road, South Yarra,
Vic 3141, Australia  Heathcote, Bernard  SASER Team, 269 Domain Road, South
Yarra, Vic 3141, Australia  Harrison, Ken M  SASER Team, 269 Domain Road,
South Yarra, Vic 3141, Australia  Johnston, Mark  SASER Team, 269 Domain Road,
South Yarra, Vic 3141, Australia  Bohlsen, Terry  SASER Team, 269 Domain Road,
South Yarra, Vic 3141, Australia  Di Scala, Giorgio  SASER Team, 269 Domain
Road, South Yarra, Vic 3141, Australia

###### Abstract

Eta Carinae ($\eta$ Car) exhibits a unique set of P Cygni profiles with both
broad and narrow components. Over many decades, the spectrum has changed –
there has been an increase in observed continuum fluxes and a decrease in Fe
ii and H i emission line equivalent widths. The spectrum is evolving towards
that of a P Cygni star such as P Cygni itself and HDE 316285. The spectral
evolution has been attributed to intrinsic variations such as a decrease in
the mass-loss rate of the primary star or differential evolution in a
latitudinal-dependent stellar wind. However intrinsic wind changes conflict
with three observational results: the steady long-term bolometric luminosity;
the repeating X-ray light curve over the binary period; and the constancy of
the dust-scattered spectrum from the Homunculus. We extend previous work that
showed a secular strengthening of P Cygni absorptions by adding more orbital
cycles to overcome temporary instabilities and by examining more atomic
transitions. cmfgen modeling of the primary wind shows that a time-decreasing
mass-loss rate is not the best explanation for the observations. However,
models with a ‘small’ dissipating absorber in our line-of-site can explain
both the increase in brightness and changes in the emission and P Cygni
absorption profiles. If the spectral evolution is caused by the dissipating
circumstellar medium, and not by intrinsic changes in the binary, the
dynamical timescale to recover from the Great Eruption is much less than a
century, different from previous suggestions.

Stars: winds, outflows - stars: individual: $\eta$ Carinae - stars: massive
-stars: mass-loss – stars: binaries

††facilities: HST, AAVSO, CTIO, Gemini/South, HST, LCOGT, ESO, MJUO, OPD/LNA,
SASER

##  1 Introduction

The $\eta$ Car spectrum recorded in the 1980s was very unusual for an LBV (or
P Cygni) star (Hillier et al., 2001a; Humphreys & Davidson, 1994). It
exhibited broad wind lines (FWHM$\sim 800$ km s-1) of H i, Fe ii, and He i
which are now understood to be associated with the primary stellar wind,
although He i is also likely to be influenced by the wind-wind collision (WWC)
zone and the radiation of the secondary star. Very prominent narrow emission
lines (FWHM$\sim$ 20–80 km s-1) of H i, He i, Fe ii and [Fe ii], superimposed
on the spectrum, arise in the Weigelt clumps (Davidson et al., 1995). Both the
Fe ii and [Fe ii] lines exhibited a broad base with similar FWHM values to
that of the primary wind lines. The broad [Fe ii] lines are unusual and are
not seen in other stars with strong stellar winds at similar excitation
regimes (e.g. HDE 316285, Hillier et al., 2001a). They are now understood to
originate in the stellar wind, but their strength relative to the stellar
continuum has been enhanced by the occulter (Hillier et al., 2001b). The same
effect makes the narrow components unexpectedly prominent.

Mehner et al. (2019), using the dusty Homunculus as a calorimeter in the
infrared, demonstrated that the binary luminosity has been reasonably constant
over the period 1968 to 2018 with possible variations associated with the
5.53-year binary orbit. Yet from 2000 to 2020 the stellar brightness increased
by more than a decade in the UV (Gull et al., 2021). The dust in the
Homunculus absorbs the bulk of the radiation from the visible into the FUV
with subsequent re-emission in the infrared. The pronounced stability of the
X-ray light curve over the past five binary cycles (Espinoza Galeas et al.,
2021; Corcoran et al., 2017) confirms that the stellar winds and their
collision have been stable over the past two decades.

Mehner et al. (2012) reported that the stellar continuum at 3950Å reflected by
Weigelt clump D stayed constant over two cycles (1999 to 2010) while the flux
of the central star increased more than ten-fold (their Fig. 12).

Damineli et al. (2019) suggested that a dissipating dusty structure that
partially occulted the central star and the extended winds would explain the
reports by Gull et al. (2009) and by Mehner et al. (2014) that while the
central star brightened in the visible and UV, the Weigelt clumps (Weigelt &
Ebersberger, 1986) remained at constant flux, leading to an effective decrease
in line equivalent widths since the EW is the line flux divided by the
continuum inside the slit.

Long-term strength decreases of some broad emission lines have been reported
based on both ground-based and STIS observations made by Mehner et al. (2010,
2011, 2012, 2015, 2019); Martin et al. (2021); Davidson et al. (2018). Those
authors suggested that the strength decrease might be due to the intrinsic
evolution of the central star and that the secular brightness increase could
be produced by a decrease in $\eta$ Car’s primary wind density or a decrease
in circumstellar extinction. Another suggestion was that the latitude-
dependent wind evolves differently in the equator and polar regions (Mehner et
al., 2015). A latitude-dependent stellar wind was previously proposed by Smith
et al. (2003b), who invoked rotation of the star as the cause. Groh et al.
(2012a) showed that these observations are more likely explained by the
ionization impact of the hot secondary modifying the primary wind structure.
Moreover, the fast-rotator LBVs show S-Doradus instabilities, not seen in slow
rotators and not present in $\eta$ Car, suggesting that $\eta$ Car might be a
slow rotator, although this is not what is expected in a binary star merger.

The trend in the system’s photometric brightness (Damineli et al., 2019) along
with a study of direct versus reflected line emission (Damineli et al., 2021,
see also Mehner et al. 2015) – suggested that the long-term weakening of the
emission lines could be better explained by a drop in circumstellar extinction
along our line-of-sight (LOS) without recourse to intrinsic changes in $\eta$
Car A.

The impact of the dissipating occulter on spectral features is complicated,
since both the line and continuum forming regions in $\eta$ Car are extended,
and since different spectral lines are formed at different locations in the
stellar wind. Thus, we first present a qualitative summary of the impact of an
occulter on the intrinsice spectrum, which is complemented by the semi-
quantitative cmfgen model described in Sect. 4.

Fig. 1 shows a schematic view of the five main regions contributing to the
observed spectrum of $\eta$ Car. Taking advantage of STIS/HST observations
makes it possible to disentangle the spectrum of the Weigelt clumps (region C)
with their nebular emission lines and reflected continuum (which are
relatively small in amplitude) from the central sources. Typical seeing from
the ground of 1 to 2 arcsec (2300 to 4600 au) while HST/STIS spatial
resolution is 0$\farcs$1 (230 au). The spectrum reflected from the Homunculus
(region D) can also be resolved (for example, at the FOS 4 position) even from
ground-based observations (Davidson & Humphreys, 1997). The central region is
unresolved and is composed of $a)$ the central star plus its inner wind
(region A) – the major source of light in the system, the source of both the
stellar continuum and the very broad P Cygni spectral features profiles; and
$b)$ the outer wind (region B) which contributes with relatively broad lines
and some continuum flux. The occulter (region E) partially blocks the wind
region but not the Weigelt clumps.

The occulter apparently blocks the central stellar core and part of the
extended primary wind. As it dissipates, the contribution from the primary
wind increases by a factor $\sim$2 while the core (continuum) increased
$\sim$10-fold.

Figure 1:  Scheme showing the five main components of the $\eta$ Car spectrum.
The $\eta$ Car image is a snapshot from a 3D simulation by Madura et al.
(2013). The structures are not to scale.

The FOS 4 region at the SE pole of the Homunculus is located at 4′′ from the
central stellar core (Davidson et al., 2005). This region receives mostly
unobstructed light from the central object (see the darker line in the upper
plot of Fig. 2), with a spectrum that is typical for an LBV star, with no
significant contribution from narrow-line components. Its spectrum was taken
with the UVES spectrograph in 2006.5 (seeing-limited, ground-based
observations) and has remained very stable since then (see Fig. 4 from
Damineli et al. 2021)111Some intrinsic, low-excitation, line emission (such as
[Ni ii] $\lambda 7378$) arises in the Homunculus but exhibits a distinct
velocity shift from the scattered emission (Hillier & Allen, 1992). A coeval
spectrum was also taken with UVES in direct view, indicated as the red
spectrum in Fig. 2. The year 2006.5 corresponds to the mid-cycle of the $\eta$
Car system ($\phi\,=\,0.52$) and fairly represents its high-excitation phase.
The wavelength range was chosen to show lines from representative ionic
species. The direct view of the star is attenuated by the (semi-transparent)
occulter, which diminishes the flux originating from the central region,
increasing the strength of narrow lines relative to the stellar continuum,
from the perspective of the observer. Gull et al. (2023) suggest that the
occulter is located at $\approx$ 1000 au from the central star and was ejected
around 1890.

Figure 2:  Ground-based (seeing-limited) high-resolution spectra of $\eta$
Car. Upper panel: The thick black line at the top shows the spectrum reflected
off the Homunculus at the FOS 4 position, observed in 2006.5. It represents an
unobstructed view of the system. H$\alpha$ emission profile in reflected light
has been decreasing by a much smaller amount than in direct light and other
emission lines have not changed. The thinner red line shows a coeval spectrum
in direct view toward the central star (presumably impacted by the occulter).
Bottom panel: direct view spectra taken in 1993.5 ( orbital phase 0.18) with
the FEROS spectrograph (thin pink line) and 2021.2 (same phase), taken with
LCOGT/NRES (thick blue line). A broad base on many of the Fe ii lines is
readily apparent. The direct spectrum has evolved towards that reflected at
FOS 4, which has evolved by a small amount.

As the occulter dissipates with time, the spectrum becomes more similar to
that of the reflected view, as shown by comparing the pink line in the bottom
plot of Fig. 2, taken in 1993.5 using ESO/FEROS, with the overplotted blue
spectrum taken in 2021.2 with LCOGT/NRES.)

The effect of the occulter on the line strength is strongly dependent on the
radial density profile of the line-formation zone plus the size, geometry, and
radial opacity profile of the occulter. An approximation of the stellar wind
structure can be inferred from the model of Hillier et al. (2001a, see their
Fig. 9). Broad Fe ii lines are formed in the outer regions of the primary’s
wind. Their intensities relative to the continuum have been decreasing with
time at a slower pace than the narrow lines formed in the Weigelt clumps. The
broad forbidden [Fe ii] lines are formed at typically larger radii than the
permitted Fe ii lines. In addition, their strength (normalized to the
continuum) has also decreased by a significant factor from 1993.5 to 2021.2,
as indicated in the bottom panel of Fig. 2. During the same period
(1993.5–2021.2), the narrow-line fluxes (normalized line strength times the
continuum flux) remained constant (Damineli et al., 2021).

Higher energy excitation lines (e.g., He i, N ii and high members of the H i
line series) are formed close to the central star, and some of them are
entirely covered by the occulter. For instance, the H ${\gamma}$ line shown in
Fig. 2 has not significantly changed over the last 28 years, while the EW of
H$\alpha$ has decreased by a factor of $\sim$2\. High-excitation permitted
lines formed behind the occulter would maintain their normalized intensity if
there was no emission from outside the occulter. However, the wind region
emits both continuum (bound-free and free-free radiation, and electron
scattering) plus line emission, and this can veil absorption lines. Further,
if the occulter extinction is large enough, the observed spectrum will be
dominated by the spectral formation in the region outside the occulter. As the
flux from the occulted region increases (when the extinction decreases), the
contribution from the central region increasingly dominates, making the
absorption lines more visible.

The presence of the hot secondary star complicates this simple scenario, as it
affects both the primary wind structure and its ionization (e.g. Mehner et
al., 2012, 2011). For most of the orbit, the higher-order Balmer lines do not
exhibit a (strong) P Cygni absorption component, which is directly
attributable to the influence of the secondary (Groh et al., 2012b). However,
strong P Cygni absorption just after periastron (i.e., when the companion is
behind the secondary and the trailing arm of the wind-wind collision structure
is in the line-of-sight) have been reported by Nielsen et al. (2007) and
Mehner et al. (2015).

The goals of this work are $a)$ to report the long-term evolution of the P
Cygni absorption components as seen from ground-based spectroscopy; $b)$ to
discuss how the strengthening of the absorption components and the weakening
of the emission line components compare with models of decreasing mass-loss
rate and with a dissipating occulter in front of $\eta$ Car.

This paper is organized as follows. In Sect. 2, we present the sources and
general characteristics of our data; in Sect. 3, we present the measurements
and their analysis; in Sect. 4, we report cmfgen modeling with normal and
enhanced mass-loss rate and two versions of occulter. Sect. 5, we discuss our
findings.

##  2 Data: observations and reduction

Table 1: Observatories

Observ. | telesc. | Res. | 5876 | 6347 | 8750 | 10830
---|---|---|---|---|---|---
| aper. | pow. | # | # | # | #
UVES | 8m | 90K | 1 | 62 | 28 | -
GMOS | 8m | 4.4K | 22 | 22 | - | -
FEROS | 1.5&2.2m | 48K | 186 | 169 | 141 | -
OPD | 1.6m | 22K | 25 | 73 | 32 | 140
Hexapod | 1.5m | 48K | 8 | - | - | -
CHIRON | 1.5m | 90K | 80 | 246 | - | -
SMARTS | 1.5m | 40K | 91 | 83 | - | -
NRES | 1m | 48K | 102 | 102 | 102 | -
HERCULES | 1m | 48K | 9 | 14 | 8 | -
M. Johnston | 0.60m | 17K | - | 5 | - | -
P. mcGee | 0.35m | 11K | 1 | 7 | - | -
P. Cacella | 0.30m | 5.5K | 13 | - | - | -
K. Harrison | 0.28m | 10K | - | 5 | - | -
B. Heatcote | 0.28m | 16K | 10 | 26 | - |
T. Bohlsen | 0.27m | 15K | 3 | 12 | - | -
G. Di Scala | 0.20m | 17K | - | 2 | - | -
STIS | 2.5m | 10K | - | - | - | -

Column 1 is the spectrograph/observer name; col. 2 the telescope aperture in
meters; col. 3 the most frequent resolving power; col. 4–7 the number of
measurements used in this work.

For the modeling, and considering we are interested in looking at the general
behavior of line strengths, it is sufficient to have two or more spectra taken
at the exact same orbital phase over a time interval long enough to enhance
the emission weakening and absorption strengthening effects. For the emission
lines, it is already proven that there is a weakening trend in the long-term
(Mehner et al., 2015; Damineli et al., 2021). For the P Cygni absorptions,
however, the past reports are confined to at most three cycles (Mehner et al.,
2015) and are better sampled around periastron. The fluctuations are large
even at mid-cycle, so the idea that they are strengthening over many cycles is
not completely stabilished. To show this, we require dense monitoring over as
many cycles as possible. The most practical quantity to use for such a time
series is the equivalent width (EW).

The data used to measure EWs in this work are mainly from the facilities
described in Damineli et al. (2021). We list those facilities in Table 1 and,
for details, we direct the reader to Sect. 2 of Damineli et al. (2021). In
addition to the professional facilities, there are a few observations from
amateur astronomers – these also listed in Table 1 and partly described in
Teodoro et al. (2016) (also see the Acknowledgments).

Most of the spectra obtained from other authors and observatories were in 1D
format (in counts versus $\lambda$), reduced with standard procedures. They
are seeing-limited ($>$ 1”), and since most of the signal from the object
originates in the central arcsec, these spectra sample similar nebular
contamination. Data from ESO/UVES and Gemini/GMOS, downloaded as 2D images
from the Treasury Project222http://etacar.umn.edu/, were used to extract 1D
spectra using all the spatial rows along the slit containing the stellar
signal to mimic the worse image quality of the other observations which used a
slit (1” wide) or fiber ($\sim$3” diameter). Even in the case of excellent
seeing, when some contribution to the signal from the Weigelt clumps could be
left outside the slit aperture, they impact only the narrow-line components,
and this work is concerned with the broad components, originating in a smaller
region. The two HST/STIS 2D spectra were downloaded from MAST
site333https://mast.stsci.edu/. To avoid as much as possible contamination by
the Weigelt clumps in STIS spectro-images, we co-added five rows around the
peak of the stellar image (0$\farcs$25-wide). Typical signal-to-noise ratios
(S$/$N) of the ground-based spectra range between 60 and 300 in the central
region, with the most frequent value $\sim$150\. On average, the lowest S$/$N
was observed for the P Cygni absorption component of He i $\lambda$10830 line,
with S/N$\sim$ 80 to 100 per pixel. This is because we use normal CCDs with
very low quantum efficiency at those wavelengths ($\sim$ 1-2%) and a large
impact because of fringing and telluric lines. Despite $\eta$ Car being a very
bright source at that wavelength, observation of a telluric standard star is
required. Other time-consuming procedures are applied in the flat-fielding to
maximize the final S/N, demanding a few hours to get a reliable spectrum.

Spectra spanning a wide wavelength range were normalized to unity by dividing
them by a high-order polynomial fit through line-free spectral windows
representing the stellar continuum. This procedure was mostly used for
visualization purposes like that presented in Fig. 2. A linear fit was used
for estimating the continuum by adopting line-free regions for spectral ranges
shorter than $\sim$ 100Å.

For EWs of absorption components, we fitted a straight line representing the
continuum across each spectral line. Two windows were chosen, one at each side
of the line, spanning sixteen pixels. For He i $\lambda$5875 the continuum
windows are centered at $\lambda$5851 and $\lambda$5930; $\lambda$6329 and
$\lambda$6400 for Si ii $\lambda$6347; $\lambda$8722 and $\lambda$8770 for H i
$\lambda$8752; $\lambda$10760 and $\lambda$11000 for He i $\lambda$10830\. The
S$/$N ratio of the continuum was measured inside the two continuum windows.
The real S$/$N of the EW is lower for the absorption and higher for the
emission, because were measured in the continuum windows.

EWs were measured by direct integration in the area between that line profile
and the projected stellar continuum. The uncertainty of individual EW
measurements ($\sigma_{\rm EW}$) was evaluated using Eq. (3) from Vollmann &
Eversberg (2006), given by:

$\sigma_{\rm
EW}=\sqrt{2}\cdot\left(\frac{\Delta\lambda-\rm{EW}}{\rm{S/N}}\right)$ (1)

where $\Delta$$\lambda$ is the wavelength interval used to integrate the flux
(in Å). Eq. 1 also accounts for the influence of small-scale irregularities
and possible faint lines in the continuum window. EW measurements with
respective errors are reported in Appendix 2, and presented in Fig. 6.

For our high-quality spectra, the largest uncertainties might not be due to
photon statistics, but rather arise from the procedures of continuum
flattening and the bias introduced by the nebular contribution which will not
be identical for each spectrograph. The only way to evaluate these
uncertainties is by comparing the coeval series of measurements taken with
different spectrographs. We did this for the epochs for which it was possible
compare measurements of at least two spectrographs. Only the EWs from the line
Si i $\lambda$6437 had overlaps between different spectrographs that were
frequent enough for this procedure. Unfortunately, the EW curve for this line
is very complicated, with large variations within a couple of months. The
scatter inside each data-sample was larger than the differences between its
average curve and the other group used to compare with it. So, no relative
shifts were applied for any EW groups.

Figure 3:  Comparison of spectral evolution obtained from HST/STIS spectra
taken at phases 10.60 and 13.64, and ground-based spectra taken at 10.73 and
13.80. The broad emission components show similar weakening in space and
ground-based data, as also is the absorption strengthening in He i
$\lambda$5875 (right panel). Narrow emission affects more the ground-based
spectra but also fills most of the N ii absorption P Cyg components (left
panel). N ii $\lambda$5710 is almost free of contamination in space and
ground-based spectra, showing similar time-strengthening behavior in both
datasets. Extraction in a lower number of rows could lead to less
contamination in STIS spectra, but this would have demanded much longer
exposures to achieve a high signal-to-noise ratio.

Line strengths were measured as follows: $a)$ the line depth intensity was
measured directly at the minimum of the P Cygni absorption component relative
to the stellar continuum and reduced by subtracting 1 (negative strength);
$b)$ the peak of broad emission lines was deblended from the narrow component
by a double Gaussian fit (narrow plus broad components) and the peak of the
broad component is the peak of the broader Gaussian. This peak also was
subtracted by the continuum (set at 1.0). This method was applied to pairs of
1993.5 and 2021.2 ground-based spectra and 2001.4 and 2018.2 STIS spectra.

##  3 Results

Previous studies of P Cygni absorption variations on He i $\lambda$6678 line
(Mehner et al., 2010, 2012), He i $\lambda$4713 and N ii $\lambda$4601-46743
(Mehner et al., 2015) have been limited to three orbital cycles. Here, we
examine a larger number of spectral lines with a denser and longer time-
sampling to monitor the spectral evolution in the optical window, using
ground-based observations.

The absorption components exhibit four types of variability: a) variability in
the depth of the P Cygni absorption components around periastron; b)
variations along the orbital cycle due to changes in the distorted shape of
the primary star’s wind caused by the WWC cavit – In most of the lines, these
variations have a relatively low amplitude when compared to the low-excitation
event around periastron; c) episodic low-amplitude variations near mid-cycle,
lasting from days to months; d) continuous, smooth, long-term low-amplitude
modulation.

The events caused by periastron passage are easily identifiable by the strong
peaks in the EW curves – the most noticeable variations start ten days before
phase zero and last for about three months – see Fig. 6. These events are
characterized by an increase in the radial velocities of the absorbing
components beyond the terminal wind speed of the primary star (420 km s-1;
Groh et al., 2012a) \- see Fig. 5.

Episodic variations are difficult to identify as they require frequent
monitoring of the EW over long time scales (years). They do not show changes
in the velocity of the line profiles in absorption at mid-cycle. We identify
those sporadic variations by analyzing the time series after subtracting the
long-term trend.

Long-term variations in absorption lines can be gleaned by comparing spectra
taken at the same phase in high-excitation phases, in different orbital
cycles, as such variations are generally larger than the sporadic low-
amplitude variations. The long-term increase in the strength of the P Cygni
absorption component is easy to see in some lines, such as He i
$\lambda$10830, but more difficult in other lines such as He i $\lambda$5875
and H i Pa12 $\lambda$8752.

Our planned modeling of the spectral evolution is based on comparison of line
profiles of two spectra taken at the same phase, sufficiently separated in
time as to have clear differences. To validate this approach and the selection
of the specific dates we follow three steps. First we compare STIS spectra
with ground-based spectra to show that they deliver compatible results, at
least for the very rare dates when this is feasible. Second, we compare
ground-based line profiles of spectra taken at the same phases in different
cycles to show that the strengthening of the P Cygni absorption is a general
property of of the spectral evolution. Third, we construct long time series of
EWs, to see what phases are most repeatable, except for the long term effect.

###  3.1  Are ground-based spectra comparable to STIS spectra to study long-
term spectral evolution?

Although the ground-based spectra have much more nebular contamination than
the STIS spectra, both data sets display a similar spectral evolution. This
can be shown by comparing the evolution in STIS spectra that were taken at the
same phase during the high-excitation state, with the evolution in ground-
based spectra, shown in Fig. 3. For this exercise, we use STIS observations
that were taken at $\phi\,=\,10.60$ and 13.64. while the almost coeval ground-
based spectra were taken at phases 10.7 and 13.80. The exact amount of line
variation is not important here. The right panel of Fig. 3 shows that the P
Cyg absorption in He i$\lambda$5875 increases with time in both STIS and
ground-based spectra while [N ii]$\lambda$5755 and NaD complex decrease. The
left panel shows the faint lines of N ii. The group member at $\lambda$5712
shows a small degree of increase with time. The other four members also show
the same trend of increase but are contaminated by nebular emissions. We tried
to diminish the length of the extraction window to 0$\farcs$1 to improve the
situation, slightly reducing the central peak of the $\lambda$5776+5680 blend,
but at the expense of decreasing the signal-to-noise ratio. This set of N ii
lines was reported by Mehner et al. (2011), who also analyzed a STIS spectrum.
They are much more evident than in the spectrum we present here. The reader
must take in mind that that spectrum was taken only five months after
periastron passage, when the absorption lines are stronger, with a much longer
time exposure and adopting a smaller( 0$\farcs$1) extraction window, leaving
almost all the nebular contamination outside the slit aperture.

To confirm the trend of strengthening of the absorption in this line, we call
attention to the report made by Davidson et al. (2015), who examined another
set of N ii lines in the range $\lambda$4601-4643 Å. They were not evident in
2003.3 and 2009.0, but appeared as stronger absorption features in 2014.5.
Those lines are stronger than in 2014.5, even in ground-based spectra taken
during the 2020 periastron. Such a comparison indicates that ground-based
spectra show similar trends to those observed from STIS observations, even in
a challenging situation like in the P Cygni absorption of N ii. This study
validates our choice for using the ground-based spectra because they comprise
many cycles with a better time sampling of the mid-cycle phases.

###  3.2  Comparison between line profiles taken at the same phase in
different orbital cycles

Figure 4: Representative line profiles at $\phi$ =9.18 – June 1993 (thin red
lines) and $\phi$ =14.18 – March 2021 (thick blue lines), showing the increase
in P Cygni absorption over the 28-year time interval and a decrease of (almost
all) emission lines at mid-cycle. Also evident is the dramatic weakening of
the narrow nebular lines, and the broad base associated with forbidden and
permitted Fe ii lines. For flux-calibrated spectra, see Fig. 2 of Damineli et
al. (2021). Horizontal dotted lines in panels $b$ and $c$ indicate the
continuum used for EW absorption measurement. Figure 5: Line profiles of Si ii
$\lambda$6347 (panels a and b) and of He i $\lambda$10830 (panel c). The inset
in panel b displays an expanded view of the absorption profile. Panel a shows
variability around periastron. Panels b and c show high-excitation phases. The
horizontal dotted line in the inset indicates the adopted stellar continuum
used for EW absorption measurements. Figure 6: Time series of EWs of the P
Cygni component in absorption. a) Si ii $\lambda$6347: this line indicates
that variability is complex even at high excitation phases; b) He i
$\lambda$10830: strengthens smoothly at high excitation; c)He i $\lambda$5875:
although the general trend is of increasing strength, there are occasional
oscillations outside of periastron; d) Paschen 12: shows transient variations
in the vicinity of periastron. Observations from different facilities are
labeled by letters and colors - a zoomed view shows more clearly the letters.
The two triangles in the upper panel indicate the dates selected for modeling
the spectra - which in reality was replaced by the FOS 4 reflected spectrum
which has no narrow lines.

Visual comparison between (a window of) two high-resolution spectra taken 28
years apart (five orbital cycles) are presented at the bottom plot of Fig. 2.
The two ground-based spectrographs, ESO/FEROS (at the 1.5$-$m ESO telescope)
and LCOGT/NRES (1-m telescope), have equal spectral resolution R $=$ 48,000
and are fiber-fed with projected entrance diameter projected on the sky of
$\sim$ 2$\farcs$7\. They were taken one year after periastron, the first in
June 1993 ($\phi$ $=$ 9.18)444In this work, we adopted the period $P$ $=$
2022.7 d reported by Teodoro et al. (2016), $T0$ $=$ 2456874.4 ($\pm$ 1.3
days) and the Groh & Damineli (2004) orbital cycle numbering scheme, in which
cycle # 14 begins at the last periastron passage on February 18, 2020. and the
second in March 2021 ($\phi\,=\,14.18$). At this phase, the spectrum has
already recovered from the “low-excitation event”. The 1993 spectrum is
representative of what has been called the “$\eta$ Car-like” spectrum.

In the $\phi\,$=$\,9.18$ spectrum, absorption profiles only appeared in lines
from very high-excitation levels of the Balmer and Paschen series, in Si ii
$\lambda$6347, and in He i lines such as He i $\lambda$4026, He i
$\lambda$4712 and He i $\lambda$10830\. During cycles 9 and 10, strong
absorption components appeared only around periastron passage – see Fig. 5.

The long-term strengthening of P Cygni components affects many other lines.
For example, Fig. 4 focuses on line-profile differences at $\phi\,=\,9.18$ and
$\phi\,=\,14.18$ for some representative lines. Panel $d$ (bottom left panel)
shows that the H$\delta$ line did not exhibit P Cygni absorption at
$\phi\,=\,9.18$, but did five orbital cycles later for the same phase. The
top-right panel of Fig. 4 $c$ shows that the P Cyg absorption of Pa 12 line -
(H i $\lambda$8752) - has strengthened, as was the case for H$\delta$,
H$\gamma$, Fe ii $\lambda$6455, He i $\lambda$5875 and He i $\lambda$4712\.
Panels $b$ and $c$ show a dotted line representing the local stellar continuum
used to integrate the EW along the absorption-line profiles.

Some spectral lines, such as Si ii $\lambda$6347 and He i $\lambda$10830, were
monitored sufficiently often to allow a comparison of their line profiles over
five or six orbital cycles. The top panel of Fig. 5 shows that far from
periastron, velocities in the absorption profiles are smaller than the
terminal velocity of $\eta$ Car primary’s wind, which is compatible with line
formation at smaller radii. From 10 days before to a month after periastron,
the profile shows very high speeds, as expected if the trailing arm of the WWC
wall passes through our LOS at those times. The middle panel of Fig. 5 shows
that the P Cygni component of Si ii $\lambda$6347 at phase 0.4 $-$ 0.6
increases with time. The bottom panel of Fig. 5 shows the same strengthening
long-term evolution of He i $\lambda$10830 P Cygni component, in this case at
$\phi$ = 0.85. An expanded view of the P Cygni absorption trend is shown in
the inset of panel c.

The evolution of these two spectral lines shows that the amplitude of both
emission and absorption variations seem to have slowed down in the last three
cycles, consistent with the almost complete disappearance of many
“circumstellar” absorption lines in the UV (Gull et al., 2021, 2023), and with
the disappearance of the blue-shifted narrow absorption of NaD (Pickett et
al., 2022).

###  3.3  EW time series of P Cygni absorption components

The comparison of spectra taken at the same phase in successive cycles is very
useful because, in principle, they would be identical if no long-term
evolution occurred. However, as we are interested in low-amplitude effects,
even minor irregularities in the orbital variations can impact the
comparisons. A more panoramic view would be assembling time series in which
such irregularities could be identified. The number of spectral lines in which
this is possible over five to six cycles is small, especially as only a few
lines show an absorption component at mid-cycle. In addition, since the
measurements come from different instruments, we had planned to scale the
different series in epochs when they are coeval. However, scaling was not
necessary in the case of some lines and not possible for others, as seen
ahead. The plots of the EW time series (Fig. 6) have the identification of
every observational point with a letter indicating its instrumental source - a
zoomed view might be necessary to see clearly the individual points.

The EW-curve of Si ii $\lambda$6347 shows an overall long-term increase but
with plenty of structures repeated over every orbital cycle (panel $a$ of Fig.
6). We call attention that the mid-cycle maximum does not occur at the exact
same phase in every cycle. This exemplifies how careful the choice of dates to
examine long-term evolution must be. The crossing of the trailing arm of the
WWC causes sharp enhancement of Si ii $\lambda$6347 absorption around
periastron passage.

The P Cygni absorption component that has the simplest time variation is that
of He i $\lambda$10830, as shown in panel b of Fig. 6. The low scatter of this
EW-curve is explained by the large intensity of this feature and, in part,
because it is recorded by the same spectrograph (OPD/Coudé) over three
decades, although using several different CCD detectors. The EW-curve shows a
smooth long-term increase at mid-cycle phases, combined with the usual narrow
peaks at periastron.

The He i $\lambda$5875 absorption component strengthens with time, but it
exhibits irregularities even at mid-cycle, differently from He i
$\lambda$10830 (see the middle panel of Fig. 6). This is due to the
contribution of the WWC in this spectral line as shown by Richardson et al.
(2016). These variations are even more pronounced at periastron passages and
are not strictly periodic. Even so, it is possible to identify a long-term
strengthening trend in the mid-cycle from cycle #10 onward. The modulus of the
radial centroid velocity of the P Cygni absorption component is $\sim$ 500 km
s-1 at mid-cycle and up to 1000 km s-1 at periastron – well beyond the
terminal speed of the wind – indicating that they are probably produced in the
WWC walls and are subject to shock instabilities. This finding aligns with the
results from Richardson et al. (2016).

Even though measurements of weak lines are subject to large uncertainties, the
absorption component of the H iPa12$\lambda$8752 line also strengthens with
time, as shown in the bottom panel of Fig. 6. Since this H i line is formed in
the innermost parts of the primary’s wind, the emission contribution from
radii outside the occulter is smaller than in lower H i transitions. Studying
this spectral line is important because it has a permanent and mostly non-
blended absorption component.

Table 2: Sample of Tables A.1 – A.4 in online material

HJD | EW 5875 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| (Å) | (Å) |
48793.994 | 0.18 | 0.09 | OPD/Coudé
48830.020 | 0.07 | 0.06 | OPD/Coudé
48838.996 | 0.05 | 0.04 | OPD/Coudé
48843.988 | 0.32 | 0.06 | OPD/Coudé
49063.609 | 0.05 | 0.04 | ESO/FEROS

HJD | EW 6347 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| (Å) | (Å) |
47918.500 | 0.16 | 0.03 | OPD/Coudé
48780.500 | 0.01 | 0.00 | OPD/Coudé
48793.990 | 0.94 | 0.19 | OPD/Coudé
48798.500 | 0.77 | 0.15 | OPD/Coudé
48825.010 | 0.04 | 0.01 | OPD/Coudé

HJD | EW 10830 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| (Å) | (Å) |
47613.590 | 0.72 | 0.12 | OPD/Coudé
47916.730 | 0.54 | 0.09 | OPD/Coudé
48020.800 | 0.32 | 0.05 | OPD/Coudé
48059.390 | 0.79 | 0.13 | OPD/Coudé
48255.760 | 1.00 | 0.17 | OPD/Coudé

HJD | EW Pa-12 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| (Å) | (Å) |
50833.750 | 0.74 | 0.15 | OPD/Coudé
50854.583 | 1.33 | 0.20 | OPD/Coudé
50946.375 | 0.74 | 0.15 | OPD/Coudé
51131.815 | 0.33 | 0.16 | ESO/FEROS
51135.819 | 0.45 | 0.23 | ESO/FEROS

Note. The first five rows of each table are presented. The full version of the
table is available online.

The EW time series provides a robust method to study the long-term
strengthening of P Cygni absorption features, which was shown in previous
reports (Mehner et al., 2010, 2012, 2015), but were restricted to shorter time
intervals. EW time series are important to track the long-term evolution of
the P Cygni absorption components. Still, many lines exhibit relatively weak
features and/or are severely blended with other spectral components. This is
why we rely on line peak/depth variation for modeling purposes.

The general evolution pattern of the observed spectrum in the last 30 years is
$a$) a strong weakening of the narrow emission lines; $b$) a general weakening
of the broad emission line components by 50% for lines formed up to large
radii in the wind (low excitation lines) and less for lines of high excitation
transitions, formed close to the central stars; $c$) a general strengthening
of P Cygni absorption components. This can be seen for representative lines in
Fig. 8 (magenta and green lines) and quantitatively (rows $1$ and $2$) of
Table 3. In this table, in addition to the line strength (rows 1 to 6), we
present the percent difference between spectra (rows 7 to 12), as indicated in
column 1. Negative numbers are produced when the line in the first spectrum is
weaker than in the second. Numbers printed in red indicate variations in the
contrary sense of observations. Differences smaller than 20% are disregarded.

##  4 cmfgen modeling

The main goal of this paper is to show that the dissipating occulter modulates
the strength of the emission and P Cygni absorption strengths in accordance
with the observed long-term spectral evolution of $\eta$ Car. Since only the
general trend of the $V$-band extinction is available (Damineli et al., 2019),
only the relative line strength is useful, not a time series with every single
EW measurement. After a careful examination of the time series in Sect. 3, we
chose two ground-based spectra taken in 1993.5 ($\phi$ = 9.18) and in 2021.2
($\phi$ = 14.18) to represent the ratio of the line-strength variation. Other
phases in mid-cycle could be used, but 0.18 is the one for which we have the
longest time interval - maximizing the spectral evolution - in addition, at
this phase – one year after the periastron – we look to the primary star
photosphere in a less-disturbed situation than in others (Madura et al.,
2013). The WWC trailing arm has already left our LOS, and the cavity is not
wholly occupying our view. Line peaks/depths offer a cleaner way than EWs to
measure line strength variations as they are less affected by blend effects on
the line wings. We call _line strength_ the peak (or depth) of the broad wind
lines above (or below) the stellar continuum. These are the quantities we use
to compare with the synthetic models and are reported in Table 3.

###  4.1 cmfgen model of the present-day unosbtructed wind

We used the cmfgen code to calculate a full wind model following (Hillier et
al., 2001a, 2006), with the following parameters:
R∗ $=$ 240 $R_{\odot}$;
$\dot{M}$ $=$ 3.9 $\times$ 10-4 $M_{\odot}\,\hbox{yr}^{-1}$;
L $=$ 4 $\times$ 106 $L_{\odot}$; and
N(H)/N(He) $=$ 10
This model is similar to that which fitted the infrared interferometry across
the Brackett alpha emission line (see Weigelt et al. 2021 and references
therein). The N(H)/N(He) ratio was increased from 5 to 10 to better explain
the influence of the occulter on the Fe ii lines. In turn, this required a
slight reduction of the mass-loss rate from 5.0 $\times$ 10-4
$M_{\odot}\,\hbox{yr}^{-1}$ to preserve the H/He i spectrum. When a fixed
solar mass fraction for iron is adopted, the Fe ii lines are weaker in the
model with a high N(H)/N(He) ratio. Qualitatively, the influence of an
occulter on a model with N(H)/N(He) $=$ 10 or 5 is not that different.
Allowing for the radiation field of the binary companion (Damineli, 1996;
Damineli et al., 1997, 2008) would provide an alternative means of weakening
the strength of Fe ii emission lines (Groh et al., 2012a).

The modeling of the unobstructed spectrum is complicated by several factors,
including:

  1. 1.

While we have an estimate of the primary’s luminosity (albeit somewhat
uncertain due to the unknown efficiency of the conversion of optical/UV light
to IR wavelengths and the luminosity of the companion), we do not have a
measurement of the intrinsic optical flux emitted by the system at optical and
UV wavelengths.

Figure 7:  An illustration of the primary star’s fully integrated spectrum
with the specific intensity for different impact parameters, $p$. This
parameter is the projected radius inside which the wind is excluded. As can be
seen from the figures, the spectra vary strongly with the impact parameter.
This variation arises due to radial variations in both ionization and density.
In the spectrum for $p\approx 2\,R_{*}$, the He i lines (.e.g., $\lambda
4471$, $\lambda 5876$) line are much stronger than in the stellar spectrum.
For $p\approx 10\,R_{*}$ H lines dominate the spectrum, while for $p\approx
90\,R_{*}$, Fe ii and [Fe ii] lines are prevalent. Thus spatial variations in
the occulter will have a strong influence on the observed spectrum. Note: If
we assume a spherical source, and ignore the occulter, the observed flux is
proportional to $\int pI(p)dp$.

  2. 2.

There is a degeneracy between the mass-loss rate and the H/He ratio, such that
similar H and He i spectra can be produced for different mass-loss rates and
H/He ratio values (Hillier et al., 2001a). Metal lines, such as He ii, can
break the degeneracy, but there are additional difficulties in modeling these
lines. For example, in models with a higher H/He ratio, the metal lines are
weaker since N(H)/N(Z) is higher (the metals are assumed to have a solar mass
fraction).

  3. 3.

The He i line strengths are most likely affected by the ionizing field of the
companion (Nielsen et al., 2007), limiting our ability to use the strength of
these lines as constraints. Therefore, in the present modeling, we demanded
that the He i lines should be weaker than in the observations.

  4. 4.

The hotter companion star ionizes the outer wind, affecting the strength of
the P Cygni profiles on Balmer lines, with low-series members (such as
H$\alpha$) being the most affected. The P Cyg absorption, especially those
associated with Fe ii lines, is also affected.

  5. 5.

The wind is optically thick, so the core radius is challenging to constrain.
However, values ranging from 60 to 240 R⊙ are roughly compatible with the
observations. In the present modeling, we adopted 240 R⊙ since this allowed us
to get a reasonable match to the higher Balmer series members without having
too much He i emission. Note: At a small core radius, the wind dominates the
formation of the optical spectrum, but as we increase the radius, the
influence of the wind declines, and the shape of the visual continuum changes.

  6. 6.

If the primary associated with $\eta$ Car is a fast rotator, there could be
significant asymmetries as suggested by (Smith et al., 2003a). However, direct
spectra taken of the central star, and those using the reflected light seen at
FOS 4 are now much more similar than in the past.

  7. 7.

The occulter may still be influencing (albeit more weakly than in the past)
the ground-based spectra. Ground-based spectra at FOS 4 are also not clean
since the spectra did show some evidence of “scattered” emission from the
Weigelt clumps (Hillier & Allen, 1992).

The main effect of the complicating factors is that we cannot develop a well-
defined model with realistic error bars. Further, the adopted parameters we
selected are generally strongly correlated. However, the parameter space of
viable models is limited. Even if some spectral lines deviate significantly
from observations, this study can produce valid results by looking at the line
ratios calculated in different astrophysical scenarios: variable mass-loss-
rate, presence or absence of a coronagraphic occulter.

The unobstructed (full wind) model is named as f.w.($\dot{M}_{\rm low}$) in
row #3 of Table 3 and is shown as a black line in Fig.8. It is intended to fit
the present-day spectrum, which we adopted as that observed in reflection at
FOS 4 (green line) - it is very similar to that of 2021.2, except for having
less narrow-line contamination and somewhat deeper absorptions. There is a
good match to emission lines, except for He i$\lambda$5875\. The broad line
component of [Fe ii]$\lambda$4815 is in reasonable agreement with the
observation. The excess emission at the peak of the FOS 4 spectrum is a
reflection from Weigelt clumps. The full wind models produce P Cygni
absorptions stronger than observed. This is a problem not solved in this and
previous papers dealing with spectral modeling with cmfgen. It may be due to
the before-mentioned peculiarities of $\eta$ Car.

###  4.2 How a mass-loss rate that decreases with time contradicts the
observed spectral evolution

To explore the effect of a larger mass-loss rate in the past, as suggested by
other authors (seenDavidson et al. 2018 and references therein) trying to
explain the decrease in emission line strengths with time, we consider a model
with a mass loss rate of 7.8 $\times$ 10-4 $M_{\odot}\,\hbox{yr}^{-1}$– twice
that of the model that fits the present-day spectrum. All other parameters,
including the terminal velocity of the wind, remained fixed. However, LBVs
typically show simultaneous changes in both the mass-loss rate and
$V_{\infty}$. No evolution in $V_{\infty}$ has been observed in the spectral
evolution of $\eta$ Car.

This unobstructed model with a 2$\times$ higher mass-loss rate is hereafter
denoted by f.w.($\dot{M}_{\rm high}$). In Fig. 8 the line profiles of the
2$\times$ mass-loss-rate are represented by the thick grey line, and the
percent difference with the model for the present-day spectrum –
f.w.($\dot{M}_{\rm low}$) – is displayed in the $9^{th}$ row of Table 3.

Figure 8:  Spectral comparisons between observations and models. Earlier dates
are in magenta and later in green. The N ii spectrum was taken with STIS and
the others are ground-based. The full wind model (black) is intended to be
compared with FOS 4 (unobstructed view) - green - the 2x mass-loss rate (grey)
is to be compared with earlier dates; the occulter with 1.6 mag extinction
(blue); and the 2.5 mag extinction occulter (orange), both to be compared with
earlier dates.

A decrease in mass-loss rate with time mimics the observed decrease in the
observed emission-line components of the Hydrogen Balmer but not in the P
Cygni components, which are weakening in the model, but remained stable in the
observations. There is an acceptable agreement between this mass-loss regime
and the 1993.5 spectrum for Fe ii$\lambda$5169, but it predicts a too faint
[Fe ii]$\lambda$4815 emission. The emission components in the model
f.w.($\dot{M}_{\rm high}$) evolve on the contrary sense to the observations
for the lines of He i and N ii. For the absorption lines of Si ii and H i Pa
12, the decreasing mass loss rate also evolves contrary to the observations.
Moreover, a decrease in the mass-loss rate is usually accompanied by an
increase in $V_{\infty}$, as seen for S Doradus stars (Leitherer et al., 1985;
Groh et al., 2009; Hillier et al., 2001a), and it would also change the X-ray
light curve contrary to what has been observed in $\eta$ Car (Espinoza-Galeas
et al., 2022).

###  4.3 cmfgen models with obstruction by the occulter

In this sub-section, we explore the effect of an obscuring ”coronagraphic”
occulter, which is dissipating or is already dissipated. In general (and
assuming the occulter lies outside the spectral formation region) the observed
flux is given by

$F=\frac{1}{d^{2}}\int\int_{\scriptstyle\rm
star\&wind}I_{\nu}(x,y)\exp(-\tau_{\nu}(x,y))dxdy$ (2)

where $I(x,y)$ is the specific intensity of the source and
$\exp(-\tau_{\nu}(x,y))$ allows for the effect of extinction. For a single
star $I_{\nu}(x,y)$ would be azimuthally symmetric on the sky, but the wind-
wind collision zone, and the influence of the radiation field of the
secondary, will break this symmetry. The substantial variation of $I_{\nu}$
with the impact parameter $p$ is shown in Fig 7 (which defines the projected
internal radius of the excluded wind flux). Unfortunately, for the choice of
$\tau_{\nu}(x,y)$ we have a wide degree of freedom. The extinction may not be
uniform, and may not be centered on the star. However, for simplicity in the
paper we limit ourselves to uniform occulters that are centered on the star.

We aim to compare the spectrum of the occulter model with that of the full
wind model. We start with the full wind model and subtract from it the
spectrum of the region obliterated by a disk. The amount subtracted is defined
by the disk size and extinction. We assume that the disk has already
dissipated (zero extinction) so that the extinction in 1993.5 is the magnitude
difference measured for the entire object (central stellar core plus the
Homunculus). The object in 1993.5 was $\Delta$ V $=$ 1.6 mag fainter than in
2021.2 and hence $A_{V}$ = 1.6 mag (Damineli et al., 2019). We adjusted the
radius of the occulter’s disk (r $=$ 22.7 Rstar) to produce a good match to
the observed H$\alpha$ line profile in 1993.5. The distance of the occulter
from the central star cannot be assessed in this work, so we adopted that
suggested by Gull et al. (2023): $d$ $\approx$ 1000 au, formed around 1890 in
the same ejection event as the Little Homunculus.

The occulter models are intended to fit the spectrum taken in 1993.5. Although
the occulter1.6 model did a good job for H$\alpha$, the upper Balmer emission
lines and He i$\lambda$ 5875 are fainter than observed in 1993.5, and the P
Cygni absorptions are stronger than predicted. Both occulter models are
broadly compatible with [Fe ii]$\lambda$4815 but their predictions are too
strong for Fe ii$\lambda$5169 as compared with observations on 1993.5.

The impact of the occulter on the spectrum cannot be guessed – it requires a
calculation using a realistic model. The complications are many: the occulter
is unlikely to be disk causing uniform extinction, and may not be centered on
the star. As different transitions originate in different regions of the wind,
the impact of the occulter is transition dependent. Further, there is
significant free-free emission from the wind which will also be influenced by
the occulter.

Table 3: Line strengths: observations versus models

|  | Emission profiles | Absorption profiles
---|---|---|---
# | Spectral lines | FeII | H$\alpha$ | H$\delta$ | FeII | [FeII] | HeI | SiII | H$\delta$ | HeI | Pa$-$12 | SiII | NII
| observations |  |
|  | 8610 | 6563 | 4101 | 4585 | 4815 | 5876 | 6347 | 4101 | 5876 | 8752 | 6347 | 5712
1 | 1993.5 | 4.6 | 61 | 4.5 | 0.8 | 0.8 | 1.9 | 0.36 | 0.00 | 0.00 |  $-$0.07 |  $-$0.05 |  $-$0.04
2 | FOS4 | 1 | 31 | 2.5 | 0.4 | 0.4 | 1.65 | 0.25 |  $-$0.20 |  $-$0.45 |  $-$0.24 |  $-$0.21 |  $-$0.06
| models |  |
3 | f.w.($\dot{M}_{\rm low}$) |  | 38 | 2.7 | 0.35 | 0.08 | 0.95 | 0.28 |  $-$0.95 |  $-$0.50 |  $-$0.40 |  $-$0.05 |  $-$0.32
4 | f.w.($\dot{M}_{\rm high}$) |  | 55 | 4.7 | 1.00 | 0.09 | 0.37 | 0.22 |  $-$0.85 |  $-$0.49 |  $-$0.55 |  $-$0.44 |  $-$0.07
5 | occulter1.6 |  | 66 | 3.2 | 1.25 | 0.23 | 0.86 | 0.21 |  $-$0.90 |  $-$0.50 |  $-$0.46 |  $-$0.16 |  $-$0.17
6 | occulter2.5 |  | 135 | 4.4 | 3.5 | 0.42 | 0.73 | 0.45 |  $-$0.36 |  $-$0.49 |  $-$0.20 |  $-$0.05 |  $-$0.12
% diff. | comparison |  |
(2$-$1)/2 | FOS4:1993.5 |  $-$360 |  $-$97 |  $-$80 |  $-$100 |  $-$100 |  $-$15 |  $-$44 | 100 | 100 | 71 | 76 | 33
(3$-$2)/3 | f.w.($\dot{M}_{\rm low}$) :FOS4 |  | 18 |  $-$11 |  $-$14 |  $-$900 |  $-$74 | 11 | 79 |  $-$28 | 40 |  $-$320 | 81
(3$-$4)/3 | f.w.($\dot{M}_{\rm low}$):f.w.($\dot{M}_{\rm high}$) |  |  $-$45 |  $-$74 |  $-$254 |  $-$13 | 61 | 21 | 11 | 2 |  $-$38 |  $-$780 | 78
(3$-$5)/3 | f.w.($\dot{M}_{\rm low}$):occulter1.6 |  |  $-$74 |  $-$19 |  $-$257 |  $-$188 | 9 | 25 | 5 | 0 |  $-$15 |  $-$220 | 0
(3$-$6)/3 | f.w.($\dot{M}_{\rm low}$):occulter2.5 |  |  $-$255 |  $-$63 |  $-$900 |  $-$425 | 23 |  $-$61 | 62 | 6 | 50 | 0 | 63
(6$-$5)/6 | occulter1.6:occulter2.5 |  |  $-$640 |  $-$38 |  $-$260 |  $-$83 | 15 |  $-$114 | 60 | 6 | 65 | 69 | 50

Notes: a) The line strength is defined by ($I/I_{c}-1$) at the line peak or
deep, negative $=$ absorption, positive $=$ emission; b)f.w. $=$ full wind;
c)$\dot{M}_{\rm low}$ = 3.9 $\times$ 10-4 $M_{\odot}\,\hbox{yr}^{-1}$,
$\dot{M}_{\rm high}$ = 7.8 $\times$ 10-4 $M_{\odot}\,\hbox{yr}^{-1}$, occulter
$=$ f.w.($\dot{M}_{\rm low}$) - see the main text; d) % differences: positive
$=$ the second is stronger;, negative $=$ the second is weaker). For N ii we
used dates 2001.1 and 2019.1. Red figures indicate line strength ratios
against the observed trend.

Between 1993.5 and 2021.2 the central star has increased in brightness by
$\Delta\,A_{V}\,$=$\,2.5$ mag, in order we consider a model where we increase
the extinction in the core by 2.5 mag, but keep the same sized occulter.
However, this model is unacceptable – it delivers a H$\alpha$ line intensity
that is quite too strong. Keeping the same extinction, we then diminished the
size of the coronagraph, obtaining $I/I_{c}-1\,=\,135$ which is much higher
than the observed value 61 in 1993.5, but not absurd. A disk with r = 10 Rstar
produced a good match to H$\delta$ and the upper Balmer series emission,
although H$\alpha$ is still too strong. The Si ii$\lambda$ 6347 is in
reasonable agreement for the emission and absorption component. N ii$\lambda$
5712 came better than in occulter1.6 model (occulter’s extinction $=$ 1.6
mag), but still too strong. No agreement was found for He i$\lambda$ 5875
emission. We call this model occulter2.5. As a general comparison, occulter2.5
produces stronger emission and weaker absorption than occulter1.6 (see row 12
in Table 3 and orange line in Fig. 8).

Future work could combine these two models with a radial profile of
extinction, decreasing from the center to the periphery. However, designing a
completely different geometry may be necessary, as Gull et al. (2023) shows
extended patterns of narrow absorption lines in the UV, and Falcke et al.
(1996) reported a knife-edge structure crossing over the central star in the
polarization map.

Table 3 offers a global comparison between observations versus models and
between models. Row 7 shows observed variations that are negative for the
emission profiles (weakening) and positive for absorptions (strengthening).
Rows 9 to 11 show differences in models that should follow the same trend as
in row 7, if they do not agree with observational trends, they are printed in
red. Variations smaller than 20% are disregarded. The occulter models with
extinction 1.6 disagree with the observational trend in 2 cases and that with
2.5 magnitudes in one case. The 2x mass-loss rate model performed worse than
the occulter models to explain the emission line weakening (four cases).
Although a complete comparison over the entire spectrum would be more
informative (if we had fine-tunned models), this set of lines representative
of high and low excitation energies validates the occulter models for
explaining the long-term evolution. Although performing worse than the two
cmfgen occulter models, the decreasing mass-loss rate model cannot be
completely ruled out on the basis of spectroscopy alone.

##  5 discussion and conclusions

We have used spectral data taken over 30 years to monitor the long-term
evolution of $\eta$ Car’s spectrum. In particular, we have studied EW time-
series of P Cygni absorption components of He i $\lambda$5875 He i
$\lambda$10830, Si ii $\lambda$6347, and H i Pa12 $\lambda$8752.

Some spectral lines like He i $\lambda$5875 and He i $\lambda$4712 suffer non-
periodic fluctuations (Richardson et al., 2015; Mehner et al., 2015) even
outside periastron. Our ability to distinguish periodic and sporadic
variations from long-term variations is enabled by the large amount of data
analyzed and because of the significant spectral evolution that has occurred
over the last three decades.

We summarize the observational results from the present work, which support
the scenario of a dissipating occulter in front of $\eta$ Car A:

  * •

Absorption P Cygni components of a set of representative lines (e.g.: upper
members of the Balmer series, He i $\lambda$5875, He i $\lambda$10830, Si ii
$\lambda$6347, N ii $\lambda$5665-5712, H i $\lambda$8752 ) have been
strengthening with time.

  * •

P Cygni absorption components are deeper in reflected than in direct light at
high excitation phases, indicating that the stellar wind formed close to the
central star suffers additional extinction along our LOS (by the occulter).

  * •

As the long-term evolution progresses, emission and absorption lines in direct
view become more similar to those reflected in the Homunculus (FOS 4
position), which has decreased much less than in direct light in H$\alpha$
emission and remained constant for other lines.

  * •

Emission lines that are formed at larger radii from the star (e.g., H$\alpha$,
Fe ii) show a stronger decrease in their line strength than those formed at
smaller radii (e.g., the upper members of the Balmer and Paschen series).
Lines formed at very small radii like N ii and to some extent He i suffer much
smaller line strength changes because the spectral line and its stellar
continuum are confined in the same region and change together.

  * •

The observed constancy of the central star while the brightness of the
Homunculus increased by $\sim$1 mag during the 1940s (Thackeray, 1953;
O’Connell & S.J., 1956), indicates that the occulter was already in place at
that time. The photometric light curve of the stellar core since before that
time could be dominated by the occulter’s dissipation.

  * •

The rate of decreasing in the emission line intensity and increasing in the
absorption maximum/minimum taken at the same phases (see Fig. 5) seems to be
decreasing slowly with time, indicating that the occulter’s dissipation might
be already ended or is close to ending. The approaching end of the dissipating
process is also hinted by the similarity between the reflected spectrum at FOS
4 and the present-day direct spectrum as shown in Fig. 2.

  * •

Although the occulter models examined in this work did not fit all the
spectral lines adequately, their percent differences with the full wind evolve
in time in the same sense as in observed spectra taken between 1993.5 and
2021.2 in this set of lines (except for Si ii$\lambda$6347). A refinement of
the occulter’s structure is likely to give better agreement with observations.

  * •

The decrease in mass-loss rate as the primary explanation for the spectral
evolution of $\eta$ Car is not strongly supported by the cmfgen models. It can
be rejected because implies in intrinsic changes in the primary star (i.e.,
changes in terminal wind speed, in the luminosity, in the X-ray light curve,
and in the reflected spectrum, at FOS 4) contrary to observations.

From the Weigelt blob constanc, we know that the occulter provides extinction
on scales of less than 0$\farcs$1 and the occulter should have a smaller
radius. Given that H$\alpha$ emission peaks around 0$\farcs$01, and Fe ii and
[Fe ii] emission at even larger radii, it is not unreasonable to assume that
differential reddening could influence the EW of absorption and emission lines
in the spectrum of $\eta$ Car, as we have demonstrated in this paper. We
speculate that the occulter could be similar to the Weigelt clumps, as it is
massive and small and might have formed in the same event. We did not identify
narrow emission lines of the occulter, probably because they are at our LOS,
differently from the Weigelt clumps which show us their ionized borders. Or it
is just an effect of smaller density?

The importance of the occulter has greatly diminished during the lifetime of
the HST. Since 1993. The visual and UV brightness has increased by roughly a
factor of 10. The increased UV brightness has led to an enhanced ionization of
the circumstellar material surrounding $\eta$ Car, and as a consequence the
disappearance of many narrow absorption lines (Gull et al., 2023). The
increase in visual brightness by a factor of 10 has caused the EW of emission
lines arising in the Weiglet blobs to be reduced by a factor of 10, making
them much less visible in the ground-based spectra. Broad forbidden lines of
Fe ii have also been greatly reduced in strength. As this brightening has
occurred, the direct spectrum has become much more similar to that seen in
reflected light (Mehner et al., 2015; Damineli et al., 2021). It is possible
that the occulter has almost dissipated (at least along our LOS). In
principle, the reddening to $\eta$ Car should then approach that of the
Weigelt blobs.

If the spectral evolution is due to a circumstellar cause, the photometric
light curve must be reviewed. Damineli et al. (2021) claim that the
brightening of the star in the last 30 years was due to the decreasing
circumstellar extinction. At first glance, the long-term photometric light-
curve variability after the 1900s looks contrary to the prediction of a
stellar merger (see Fig. 2 of Schneider et al. 2019) since it predicts a slow
decrease of bolometric luminosity as compared to the rapid increase in $\eta$
Car brightness in the last 30 years. However, suppose these variations are
driven by changes in the circumstellar medium, as suggested by the dissipating
occulter. One additional test would be the disappearance of HCN molecular
absorption in front of the star, reported by Bordiu & Rizzo (2019) using ALMA.

In that case, the star is much more constant than claimed before and would
indicate a dormant LBV, like the other non-S Dor variable LBVs, including P
Cygni, HD 316285, and HD 168625. In this context, there is no contradiction
between the $\eta$ Car light curve and the binary merger scenario as shown by
Schneider et al. (2019). In this scenario, the recovery from the Great
Eruption of the 19th century occurred rapidly, on a timescale of less than a
century.

##  6 Data Availability

The complete versions of Tables 1-4 are available in the online journal in a
machine-readable format following the CDS/Vizier standards.

##  7 Acknowledgments

We thank D.S.C. Damineli for adapting our plots to color-blind people. AD
thanks to CNPq (301490/2019-8) and FAPESP (2011/51680-6) for their support.
The work of FN is supported by NOIRLab, which is managed by the Association of
Universities for Research in Astronomy (AURA) under a cooperative agreement
with the National Science Foundation. AFJM is grateful for financial aid from
NSERC (Canada). This work is partially based on observations collected with
the facilities listed below. DJH gratefully acknowledges support from STScI
grants HST-AR-14568.001-A and HST-AR-16131.001-A. CMPR acknowledges support
from NATA ATP grant 80NSSC22K0628 and NASA Chandra Theory grant TM2-23003X.

Based on observations collected at the European Southern Observatory, Chile
under Prog-IDs: UVES: 60.A-9022(A), 70.D-0607(A), 71.D-0168(A), 072.D-0524(A),
074.D-0141(A), 077.D-0618(A), 380.D-0036(A), 381.D-0004(A),282.D-5073(A, B, C,
D, E), 089.D-0024(A), 592.D-0047(A, B, C). The first three programmes were
described in Stahl et al. (2005) and the others in Mehner et al. (2015); FEROS
(partial list): 00.A-0000(A), 69.D-0378(A),, 69.D-0381(A),
71.D-0554(A),079.D-0564(C), 079.A-9201(A), 081.D-2008(A), 082.A-9208(A),
082.A-9209(A), 082.A-9210(A), 083.D-0589(A), 086.D-0997(A),
087.D-0946(A),089.D-0975(A), 098.A-9007(A). Spectra can be downloaded from the
ESO database by using the instrument name (UVES or FEROS) plus the Julian Date
provided in the Appendix Tables.

Based on observations made at the Coudé focus of the 1.6-m telescope for the
Observatório do Pico dos Dias/LNA (Brazil).

Based in part on data from Mt. John University Observatory: MJUO -University
of Canterbury - New Zealand).

Based in part on observations obtained through NOIR Lab (formerly NOAO)
allocations of NOAO-09B-153, NOAO-12A-216, NOAO-12B-194, NOAO-13B-328,
NOAO-15A-0109, NOAO-18A-0295, NOAO-19B204, NOIRLab-20A-0054, and
NOIRLab-21B-0334. This research has used data from the CTIO/SMARTS 1.5m
telescope, which is operated as part of the SMARTS Consortium by RECONS
(www.recons.org) members Todd Henry, Hodari James, Wei-Chun Jao, and Leonardo
Paredes. At the telescope, observations were carried out by Roberto Aviles and
Rodrigo.

Based on observations obtained at the international Gemini Observatory, a
program of NSF NOIRLab, which is managed by the Association of Universities
for Research in Astronomy (AURA) under a cooperative agreement with the
National Science Foundation on behalf of the Gemini Observatory partnership:
the National Science Foundation (United States), National Research Council
(Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio
de Ciencia, Tecnología e Innovación (Argentina), Ministério da Ciência,
Tecnologia, Inovações e Comunicações (Brazil), and Korea Astronomy and Space
Science Institute (Republic of Korea).

Based on observations with the NASA/ESA Hubble Space Telescope, obtained (from
the Data Archive) at the Space Telescope Science Institute, which is operated
by the Association of Universities for Research in Astronomy, Inc., under NASA
contract NAS 5-26555. These two observations are associated with programmes
8619 and 15067 - PI K. Davidson - link: https://mast.stsci.edu/search/ui/#/hst

The ESO/UVES and Gemini S/GMOS spectra used in this paper were downloaded from
the HST Treasury Project archive at http://etacar.umn.edu/.

We acknowledge with thanks the variable star observations from
https://www.aavso.org/ contributed by observers worldwide and used in this
research.

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##  Appendix A Extended data tables (online material)

Table 4: Equivalent widths of the 5875 Å absorption feature. HJD | EW 5875 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| ((Å)) | ((Å)) |
48793.994 | 0.18 | 0.09 | OPD/Coudé
48830.020 | 0.07 | 0.06 | OPD/Coudé
48838.996 | 0.05 | 0.04 | OPD/Coudé
48843.988 | 0.32 | 0.06 | OPD/Coudé
49063.609 | 0.05 | 0.04 | ESO/FEROS
49063.609 | 0.10 | 0.08 | ESO/FEROS
49065.609 | 0.10 | 0.08 | ESO/FEROS
49066.621 | 0.10 | 0.08 | ESO/FEROS
49067.605 | 0.10 | 0.08 | ESO/FEROS
49068.609 | 0.09 | 0.07 | ESO/FEROS
49069.609 | 0.10 | 0.08 | ESO/FEROS
49071.613 | 0.10 | 0.08 | ESO/FEROS
49072.613 | 0.09 | 0.07 | ESO/FEROS
49073.648 | 0.06 | 0.05 | ESO/FEROS
49074.625 | 0.09 | 0.07 | ESO/FEROS
49075.574 | 0.08 | 0.06 | ESO/FEROS
49076.625 | 0.09 | 0.07 | ESO/FEROS
49077.590 | 0.08 | 0.07 | ESO/FEROS
49078.613 | 0.08 | 0.06 | ESO/FEROS
49079.605 | 0.07 | 0.06 | ESO/FEROS
49080.605 | 0.06 | 0.05 | ESO/FEROS
49081.609 | 0.06 | 0.05 | ESO/FEROS
49082.609 | 0.09 | 0.07 | ESO/FEROS
49083.598 | 0.04 | 0.04 | ESO/FEROS
49084.598 | 0.09 | 0.07 | ESO/FEROS
49085.598 | 0.09 | 0.07 | ESO/FEROS
49086.605 | 0.05 | 0.04 | ESO/FEROS
49087.602 | 0.02 | 0.02 | ESO/FEROS
49088.609 | 0.06 | 0.05 | ESO/FEROS
49089.621 | 0.07 | 0.06 | ESO/FEROS
49089.621 | 0.08 | 0.06 | ESO/FEROS
49090.605 | 0.03 | 0.03 | ESO/FEROS
49095.590 | 0.07 | 0.05 | ESO/FEROS
49098.625 | 0.06 | 0.05 | ESO/FEROS
49098.688 | 0.07 | 0.06 | ESO/FEROS
49100.605 | 0.07 | 0.05 | ESO/FEROS
49101.605 | 0.07 | 0.05 | ESO/FEROS
49102.605 | 0.08 | 0.06 | ESO/FEROS
49104.617 | 0.06 | 0.05 | ESO/FEROS
49105.605 | 0.02 | 0.01 | ESO/FEROS
49106.605 | 0.05 | 0.04 | ESO/FEROS
49108.602 | 0.04 | 0.03 | ESO/FEROS
49110.684 | 0.05 | 0.04 | ESO/FEROS
49110.684 | 0.07 | 0.06 | ESO/FEROS
49112.680 | 0.02 | 0.02 | ESO/FEROS
49113.578 | 0.03 | 0.03 | ESO/FEROS
49118.563 | 0.03 | 0.02 | ESO/FEROS
49120.676 | 0.04 | 0.04 | ESO/FEROS
49122.527 | 0.05 | 0.04 | ESO/FEROS
49122.527 | 0.05 | 0.04 | ESO/FEROS
49123.637 | 0.05 | 0.04 | ESO/FEROS
49124.539 | 0.07 | 0.05 | ESO/FEROS
49125.535 | 0.08 | 0.07 | ESO/FEROS
49127.617 | 0.06 | 0.05 | ESO/FEROS
49129.543 | 0.04 | 0.03 | ESO/FEROS
49130.543 | 0.08 | 0.06 | ESO/FEROS
49132.625 | 0.08 | 0.06 | ESO/FEROS
49134.625 | 0.02 | 0.02 | ESO/FEROS
49134.625 | 0.03 | 0.02 | ESO/FEROS
49137.645 | 0.07 | 0.06 | ESO/FEROS
49138.590 | 0.03 | 0.02 | ESO/FEROS
49395.867 | 0.17 | 0.09 | ESO/FEROS
49408.532 | 0.24 | 0.12 | ESO/FEROS
49424.523 | 0.18 | 0.09 | ESO/FEROS
49448.605 | 0.28 | 0.06 | ESO/FEROS
49467.564 | 0.37 | 0.07 | ESO/FEROS
49472.599 | 0.45 | 0.09 | ESO/FEROS
49514.541 | 0.27 | 0.05 | ESO/FEROS
49520.612 | 0.27 | 0.05 | ESO/FEROS
49522.539 | 0.29 | 0.06 | ESO/FEROS
49525.528 | 0.28 | 0.06 | ESO/FEROS
49527.526 | 0.32 | 0.06 | ESO/FEROS
49532.520 | 0.33 | 0.07 | ESO/FEROS
49534.504 | 0.32 | 0.06 | ESO/FEROS
49751.220 | 0.14 | 0.07 | OPD/Coudé
49770.240 | 0.15 | 0.08 | OPD/Coudé
49786.120 | 0.14 | 0.07 | OPD/Coudé
49786.120 | 0.14 | 0.07 | OPD/Coudé
49800.240 | 0.13 | 0.07 | OPD/Coudé
49800.240 | 0.14 | 0.07 | OPD/Coudé
49821.230 | 0.10 | 0.08 | OPD/Coudé
49846.040 | 0.09 | 0.07 | OPD/Coudé
49860.070 | 0.07 | 0.06 | OPD/Coudé
50120.783 | 0.05 | 0.04 | ESO/FEROS
50146.869 | 0.05 | 0.04 | ESO/FEROS
50160.749 | 0.05 | 0.04 | ESO/FEROS
50174.758 | 0.10 | 0.08 | ESO/FEROS
50188.813 | 0.06 | 0.05 | ESO/FEROS
50201.733 | 0.06 | 0.05 | ESO/FEROS
50238.467 | 0.13 | 0.07 | ESO/FEROS
50238.484 | 0.14 | 0.07 | ESO/FEROS
50238.513 | 0.06 | 0.05 | ESO/FEROS
50242.454 | 0.09 | 0.07 | ESO/FEROS
50242.471 | 0.10 | 0.08 | ESO/FEROS
50242.487 | 0.07 | 0.06 | ESO/FEROS
50244.563 | 0.06 | 0.05 | ESO/FEROS
50244.581 | 0.06 | 0.05 | ESO/FEROS
50244.598 | 0.09 | 0.08 | ESO/FEROS
50449.736 | 0.29 | 0.06 | ESO/FEROS
50449.757 | 0.29 | 0.06 | ESO/FEROS
50450.772 | 0.29 | 0.06 | ESO/FEROS
50450.787 | 0.31 | 0.06 | ESO/FEROS
50451.692 | 0.32 | 0.06 | ESO/FEROS
50451.706 | 0.29 | 0.06 | ESO/FEROS
50451.720 | 0.32 | 0.06 | ESO/FEROS
50453.719 | 0.33 | 0.07 | ESO/FEROS
50454.733 | 0.34 | 0.07 | ESO/FEROS
50455.798 | 0.28 | 0.06 | ESO/FEROS
50455.825 | 0.32 | 0.06 | ESO/FEROS
50456.705 | 0.33 | 0.07 | ESO/FEROS
50456.719 | 0.37 | 0.07 | ESO/FEROS
50456.733 | 0.38 | 0.08 | ESO/FEROS
50457.676 | 0.37 | 0.07 | ESO/FEROS
50457.690 | 0.33 | 0.07 | ESO/FEROS
50457.703 | 0.35 | 0.07 | ESO/FEROS
50464.836 | 0.29 | 0.06 | ESO/FEROS
50464.848 | 0.32 | 0.06 | ESO/FEROS
50464.857 | 0.34 | 0.07 | ESO/FEROS
50464.867 | 0.34 | 0.07 | ESO/FEROS
50472.866 | 0.30 | 0.06 | ESO/FEROS
50472.876 | 0.28 | 0.06 | ESO/FEROS
50476.826 | 0.25 | 0.05 | ESO/FEROS
50476.839 | 0.24 | 0.12 | ESO/FEROS
50476.851 | 0.31 | 0.06 | ESO/FEROS
50476.864 | 0.29 | 0.06 | ESO/FEROS
50472.876 | 0.28 | 0.06 | ESO/FEROS
50476.826 | 0.25 | 0.05 | ESO/FEROS
50476.839 | 0.24 | 0.12 | ESO/FEROS
50476.851 | 0.31 | 0.06 | ESO/FEROS
50476.864 | 0.29 | 0.06 | ESO/FEROS
50516.677 | 0.19 | 0.10 | ESO/FEROS
50516.687 | 0.29 | 0.06 | ESO/FEROS
50518.615 | 0.22 | 0.11 | ESO/FEROS
50518.624 | 0.19 | 0.10 | ESO/FEROS
50518.633 | 0.19 | 0.10 | ESO/FEROS
50520.655 | 0.26 | 0.05 | ESO/FEROS
50527.619 | 0.25 | 0.05 | ESO/FEROS
50527.629 | 0.25 | 0.05 | ESO/FEROS
50527.640 | 0.21 | 0.11 | ESO/FEROS
50531.638 | 0.23 | 0.11 | ESO/FEROS
50531.649 | 0.20 | 0.10 | ESO/FEROS
50531.659 | 0.20 | 0.10 | ESO/FEROS
50533.625 | 0.20 | 0.10 | ESO/FEROS
50533.635 | 0.17 | 0.08 | ESO/FEROS
50535.669 | 0.25 | 0.05 | ESO/FEROS
50535.679 | 0.22 | 0.11 | ESO/FEROS
50535.689 | 0.29 | 0.06 | ESO/FEROS
50537.651 | 0.25 | 0.05 | ESO/FEROS
50537.661 | 0.28 | 0.06 | ESO/FEROS
50537.671 | 0.25 | 0.05 | ESO/FEROS
50539.660 | 0.31 | 0.06 | ESO/FEROS
50539.670 | 0.31 | 0.06 | ESO/FEROS
50541.670 | 0.25 | 0.05 | ESO/FEROS
50545.654 | 0.31 | 0.06 | ESO/FEROS
50545.664 | 0.27 | 0.05 | ESO/FEROS
50547.656 | 0.37 | 0.07 | ESO/FEROS
50547.666 | 0.28 | 0.06 | ESO/FEROS
50549.658 | 0.27 | 0.05 | ESO/FEROS
50549.668 | 0.19 | 0.09 | ESO/FEROS
50551.673 | 0.37 | 0.07 | ESO/FEROS
50551.683 | 0.26 | 0.05 | ESO/FEROS
50553.675 | 0.23 | 0.11 | ESO/FEROS
50556.579 | 0.31 | 0.06 | ESO/FEROS
50556.582 | 0.27 | 0.05 | ESO/FEROS
50556.583 | 0.25 | 0.05 | ESO/FEROS
50557.603 | 0.33 | 0.07 | ESO/FEROS
50557.607 | 0.30 | 0.06 | ESO/FEROS
50559.578 | 0.26 | 0.05 | ESO/FEROS
50559.579 | 0.21 | 0.11 | ESO/FEROS
50559.582 | 0.20 | 0.10 | ESO/FEROS
50561.578 | 0.33 | 0.07 | ESO/FEROS
50563.581 | 0.19 | 0.10 | ESO/FEROS
50563.584 | 0.30 | 0.06 | ESO/FEROS
50563.586 | 0.33 | 0.07 | ESO/FEROS
50565.574 | 0.35 | 0.07 | ESO/FEROS
50565.575 | 0.32 | 0.06 | ESO/FEROS
50762.375 | 0.52 | 0.10 | OPD/Coudé
51131.815 | 0.05 | 0.04 | ESO/FEROS
51131.815 | 0.39 | 0.08 | ESO/FEROS
51131.823 | 0.36 | 0.07 | ESO/FEROS
51131.826 | 0.33 | 0.07 | ESO/FEROS
51135.819 | 0.02 | 0.02 | ESO/FEROS
51142.820 | 0.06 | 0.05 | ESO/FEROS
51148.820 | 0.07 | 0.06 | ESO/FEROS
51150.845 | 0.09 | 0.07 | ESO/FEROS
51153.861 | 0.10 | 0.08 | ESO/FEROS
51154.868 | 0.05 | 0.04 | ESO/FEROS
51155.872 | 0.05 | 0.04 | ESO/FEROS
51156.880 | 0.04 | 0.03 | ESO/FEROS
51171.708 | 0.08 | 0.07 | ESO/FEROS
51173.725 | 0.04 | 0.03 | ESO/FEROS
51175.725 | 0.05 | 0.04 | ESO/FEROS
51178.869 | 0.06 | 0.05 | ESO/FEROS
51181.881 | 0.04 | 0.04 | ESO/FEROS
51183.883 | 0.02 | 0.02 | ESO/FEROS
51187.884 | 0.04 | 0.03 | ESO/FEROS
51196.896 | 0.02 | 0.02 | ESO/FEROS
51373.459 | 0.05 | 0.04 | ESO/FEROS
51374.481 | 0.13 | 0.07 | ESO/FEROS
51375.448 | 0.07 | 0.05 | ESO/FEROS
51376.477 | 0.06 | 0.05 | ESO/FEROS
51379.459 | 0.07 | 0.06 | ESO/FEROS
51380.497 | 0.07 | 0.05 | ESO/FEROS
51381.485 | 0.08 | 0.07 | ESO/FEROS
51382.476 | 0.10 | 0.08 | ESO/FEROS
51383.466 | 0.10 | 0.08 | ESO/FEROS
51384.457 | 0.06 | 0.05 | ESO/FEROS
51385.479 | 0.08 | 0.06 | ESO/FEROS
51386.459 | 0.08 | 0.06 | ESO/FEROS
51387.502 | 0.09 | 0.08 | ESO/FEROS
51388.463 | 0.16 | 0.08 | ESO/FEROS
51389.457 | 0.09 | 0.07 | ESO/FEROS
51390.461 | 0.06 | 0.05 | ESO/FEROS
51391.496 | 0.05 | 0.04 | ESO/FEROS
51392.470 | 0.05 | 0.04 | ESO/FEROS
51393.483 | 0.11 | 0.06 | ESO/FEROS
51394.471 | 0.11 | 0.09 | ESO/FEROS
51873.500 | 0.30 | 0.06 | OPD/Coudé
52459.479 | 0.60 | 0.12 | OPD/Coudé
52818.375 | 0.93 | 0.14 | OPD/Coudé
52825.375 | 1.05 | 0.16 | OPD/Coudé
52825.505 | 0.58 | 0.12 | ESO/UVES
52987.375 | 0.44 | 0.09 | OPD/Coudé
53583.375 | 0.17 | 0.08 | OPD/Coudé
54191.440 | 0.55 | 0.11 | OPD/Coudé
54191.442 | 0.50 | 0.10 | OPD/Coudé
54208.500 | 0.30 | 0.06 | Gemini S/GMOS
54281.500 | 0.32 | 0.06 | Gemini S/GMOS
54550.500 | 0.15 | 0.07 | Gemini S/GMOS
54601.024 | 0.33 | 0.07 | ESO/FEROS
54601.524 | 0.34 | 0.07 | ESO/FEROS
54601.524 | 0.36 | 0.07 | ESO/FEROS
54653.963 | 0.47 | 0.09 | Gemini S/GMOS
54778.500 | 0.40 | 0.08 | Gemini S/GMOS
54797.500 | 0.41 | 0.08 | Gemini S/GMOS
54818.500 | 0.33 | 0.07 | Gemini S/GMOS
54821.830 | 0.44 | 0.09 | ESO/FEROS
54821.834 | 0.34 | 0.07 | ESO/FEROS
54821.835 | 0.35 | 0.07 | ESO/FEROS
54821.840 | 0.24 | 0.12 | ESO/FEROS
54821.844 | 0.35 | 0.07 | ESO/FEROS
54821.848 | 0.29 | 0.06 | ESO/FEROS
54822.868 | 0.26 | 0.05 | ESO/FEROS
54822.869 | 0.37 | 0.07 | ESO/FEROS
54822.871 | 0.32 | 0.06 | ESO/FEROS
54822.873 | 0.30 | 0.06 | ESO/FEROS
54823.792 | 0.40 | 0.08 | ESO/FEROS
54823.793 | 0.34 | 0.07 | ESO/FEROS
54823.797 | 0.31 | 0.06 | ESO/FEROS
54824.815 | 0.30 | 0.06 | ESO/FEROS
54824.816 | 0.28 | 0.06 | ESO/FEROS
54824.818 | 0.34 | 0.07 | ESO/FEROS
54824.821 | 0.37 | 0.07 | ESO/FEROS
54825.500 | 0.39 | 0.08 | Gemini S/GMOS
54825.797 | 0.29 | 0.06 | ESO/FEROS
54825.798 | 0.30 | 0.06 | ESO/FEROS
54825.800 | 0.22 | 0.11 | ESO/FEROS
54825.802 | 0.29 | 0.06 | ESO/FEROS
54827.867 | 0.27 | 0.05 | ESO/FEROS
54827.868 | 0.29 | 0.06 | ESO/FEROS
54827.869 | 0.33 | 0.07 | ESO/FEROS
54827.871 | 0.23 | 0.11 | ESO/FEROS
54828.867 | 0.31 | 0.06 | ESO/FEROS
54829.867 | 0.40 | 0.08 | ESO/FEROS
54829.868 | 0.34 | 0.07 | ESO/FEROS
54829.869 | 0.32 | 0.06 | ESO/FEROS
54829.871 | 0.38 | 0.08 | ESO/FEROS
54830.872 | 0.36 | 0.07 | ESO/FEROS
54830.873 | 0.32 | 0.06 | ESO/FEROS
54830.875 | 0.32 | 0.06 | ESO/FEROS
54830.876 | 0.38 | 0.08 | ESO/FEROS
54831.500 | 0.44 | 0.09 | Gemini S/GMOS
54831.873 | 0.42 | 0.08 | ESO/FEROS
54831.874 | 0.32 | 0.06 | ESO/FEROS
54831.875 | 0.39 | 0.08 | ESO/FEROS
54831.877 | 0.36 | 0.07 | ESO/FEROS
54832.870 | 0.37 | 0.07 | ESO/FEROS
54832.871 | 0.43 | 0.09 | ESO/FEROS
54832.872 | 0.47 | 0.09 | ESO/FEROS
54832.874 | 0.44 | 0.09 | ESO/FEROS
54833.866 | 0.53 | 0.11 | ESO/FEROS
54833.867 | 0.46 | 0.09 | ESO/FEROS
54833.869 | 0.42 | 0.08 | ESO/FEROS
54833.870 | 0.39 | 0.08 | ESO/FEROS
54834.879 | 0.59 | 0.12 | ESO/FEROS
54834.880 | 0.51 | 0.10 | ESO/FEROS
54834.882 | 0.50 | 0.10 | ESO/FEROS
54834.883 | 0.54 | 0.11 | ESO/FEROS
54835.375 | 0.61 | 0.12 | OPD/Coudé
54835.500 | 0.56 | 0.11 | Gemini S/GMOS
54840.500 | 1.14 | 0.17 | Gemini S/GMOS
54843.500 | 1.28 | 0.19 | Gemini S/GMOS
54845.856 | 1.26 | 0.19 | ESO/Hexapod
54851.720 | 0.64 | 0.13 | ESO/Hexapod
54852.500 | 0.22 | 0.11 | Gemini S/GMOS
54852.500 | 0.40 | 0.08 | Gemini S/GMOS
54855.500 | 0.11 | 0.05 | Gemini S/GMOS
54860.500 | 0.02 | 0.02 | Gemini S/GMOS
54867.500 | 0.03 | 0.02 | Gemini S/GMOS
54874.738 | 0.12 | 0.06 | ESO/Hexapod
54877.721 | 0.14 | 0.07 | ESO/Hexapod
54881.500 | 0.19 | 0.09 | Gemini S/GMOS
54882.725 | 0.32 | 0.06 | ESO/Hexapod
54887.688 | 0.39 | 0.08 | ESO/Hexapod
54891.687 | 0.50 | 0.10 | ESO/Hexapod
54896.716 | 0.65 | 0.13 | ESO/Hexapod
54907.500 | 1.17 | 0.18 | Gemini S/GMOS
54949.500 | 0.37 | 0.07 | Gemini S/GMOS
54953.599 | 0.51 | 0.10 | ESO/FEROS
54953.600 | 0.49 | 0.10 | ESO/FEROS
54953.602 | 0.50 | 0.10 | ESO/FEROS
54955.585 | 0.54 | 0.11 | ESO/FEROS
54955.587 | 0.45 | 0.09 | ESO/FEROS
54955.588 | 0.54 | 0.11 | ESO/FEROS
54955.588 | 0.52 | 0.10 | ESO/FEROS
55036.500 | 0.79 | 0.12 | Gemini S/GMOS
55204.500 | 0.62 | 0.12 | Gemini S/GMOS
55989.692 | 0.42 | 0.08 | CTIO/Chiron
55993.755 | 0.46 | 0.09 | CTIO/Chiron
56001.729 | 0.53 | 0.11 | CTIO/Chiron
56013.689 | 0.42 | 0.08 | CTIO/Chiron
56221.888 | 0.66 | 0.13 | CTIO/Chiron
56236.844 | 0.66 | 0.13 | CTIO/Chiron
56238.867 | 0.63 | 0.13 | CTIO/Chiron
56248.812 | 0.70 | 0.14 | CTIO/Chiron
56254.880 | 0.74 | 0.08 | CTIO/Chiron
56260.781 | 0.78 | 0.12 | CTIO/Chiron
56275.818 | 0.89 | 0.13 | CTIO/Chiron
56289.797 | 0.87 | 0.13 | CTIO/Chiron
56361.647 | 1.10 | 0.17 | CTIO/Chiron
56401.591 | 1.04 | 0.16 | CTIO/Chiron
56417.592 | 0.89 | 0.13 | CTIO/Chiron
56607.843 | 1.19 | 0.18 | CTIO/Chiron
56612.865 | 1.07 | 0.16 | CTIO/Chiron
56656.703 | 0.76 | 0.11 | CTIO/Chiron
56659.709 | 0.64 | 0.13 | CTIO/Chiron
56664.675 | 0.63 | 0.13 | CTIO/Chiron
56670.783 | 0.71 | 0.14 | CTIO/Chiron
56672.838 | 0.76 | 0.11 | CTIO/Chiron
56677.760 | 0.81 | 0.12 | CTIO/Chiron
56687.709 | 0.73 | 0.15 | CTIO/Chiron
56690.692 | 0.72 | 0.14 | CTIO/Chiron
56697.727 | 0.72 | 0.14 | CTIO/Chiron
56710.670 | 0.65 | 0.13 | CTIO/Chiron
56712.694 | 0.57 | 0.11 | CTIO/Chiron
56718.712 | 0.74 | 0.11 | CTIO/Chiron
56725.571 | 0.70 | 0.14 | CTIO/Chiron
56729.562 | 0.71 | 0.14 | CTIO/Chiron
56732.606 | 0.39 | 0.08 | CTIO/Chiron
56739.549 | 0.22 | 0.11 | CTIO/Chiron
56746.520 | 0.28 | 0.06 | CTIO/Chiron
56750.542 | 0.32 | 0.06 | CTIO/Chiron
56754.554 | 0.43 | 0.09 | CTIO/Chiron
56765.590 | 0.72 | 0.14 | CTIO/Chiron
56766.546 | 0.79 | 0.12 | CTIO/Chiron
56767.512 | 0.82 | 0.12 | CTIO/Chiron
56774.547 | 0.88 | 0.13 | CTIO/Chiron
56781.474 | 1.03 | 0.15 | CTIO/Chiron
56787.500 | 1.26 | 0.19 | MJUO/Hercules
56788.500 | 1.24 | 0.19 | MJUO/Hercules
56791.553 | 1.25 | 0.19 | CTIO/Chiron
56795.509 | 1.34 | 0.20 | CTIO/Chiron
56800.464 | 1.44 | 0.22 | CTIO/Chiron
56801.500 | 1.43 | 0.21 | CTIO/Chiron
56803.529 | 1.51 | 0.23 | CTIO/Chiron
56810.484 | 1.43 | 0.21 | CTIO/Chiron
56818.506 | 0.63 | 0.13 | CTIO/Chiron
56819.529 | 0.56 | 0.11 | CTIO/Chiron
56822.500 | 0.80 | 0.12 | MJUO/Hercules
56823.540 | 0.51 | 0.10 | CTIO/Chiron
56824.500 | 0.85 | 0.13 | MJUO/Hercules
56824.518 | 0.52 | 0.10 | CTIO/Chiron
56827.500 | 0.88 | 0.13 | MJUO/Hercules
56828.500 | 0.89 | 0.13 | MJUO/Hercules
56829.503 | 0.62 | 0.12 | CTIO/Chiron
56832.502 | 0.85 | 0.13 | CTIO/Chiron
56835.535 | 0.56 | 0.11 | CTIO/Chiron
56836.498 | 0.54 | 0.11 | CTIO/Chiron
56850.510 | 0.80 | 0.12 | CTIO/Chiron
56851.985 | 0.61 | 0.12 | SASER/TB
56855.458 | 0.68 | 0.14 | CTIO/Chiron
56855.500 | 1.07 | 0.16 | MJUO/Hercules
56857.453 | 0.85 | 0.13 | CTIO/Chiron
56858.452 | 0.87 | 0.13 | CTIO/Chiron
56859.465 | 0.94 | 0.14 | CTIO/Chiron
56863.465 | 1.31 | 0.20 | CTIO/Chiron
56864.467 | 1.52 | 0.23 | CTIO/Chiron
56866.511 | 1.49 | 0.22 | CTIO/Chiron
56867.464 | 1.60 | 0.24 | CTIO/Chiron
56870.455 | 0.99 | 0.15 | CTIO/Chiron
56872.463 | 0.75 | 0.11 | CTIO/Chiron
56873.463 | 0.67 | 0.13 | CTIO/Chiron
56874.454 | 0.51 | 0.10 | CTIO/Chiron
56875.500 | 1.24 | 0.19 | MJUO/Hercules
56878.482 | 0.34 | 0.07 | CTIO/Chiron
56879.466 | 0.36 | 0.07 | CTIO/Chiron
56880.466 | 0.36 | 0.07 | CTIO/Chiron
56881.465 | 0.36 | 0.07 | CTIO/Chiron
56882.461 | 0.29 | 0.06 | CTIO/Chiron
56883.465 | 0.29 | 0.06 | CTIO/Chiron
56885.462 | 0.26 | 0.05 | CTIO/Chiron
56886.469 | 0.22 | 0.11 | CTIO/Chiron
56887.460 | 0.18 | 0.09 | CTIO/Chiron
56887.460 | 0.18 | 0.09 | CTIO/Chiron
56941.907 | 0.61 | 0.12 | CTIO/Chiron
56942.907 | 0.66 | 0.13 | CTIO/Chiron
56944.897 | 0.69 | 0.14 | CTIO/Chiron
56950.875 | 0.63 | 0.13 | CTIO/Chiron
56952.865 | 0.71 | 0.14 | CTIO/Chiron
56953.880 | 0.72 | 0.14 | CTIO/Chiron
56954.831 | 0.74 | 0.11 | CTIO/Chiron
56955.861 | 0.71 | 0.14 | CTIO/Chiron
56956.874 | 0.67 | 0.13 | CTIO/Chiron
56957.890 | 0.69 | 0.14 | CTIO/Chiron
56958.864 | 0.72 | 0.14 | CTIO/Chiron
56959.847 | 0.74 | 0.11 | CTIO/Chiron
56961.848 | 0.73 | 0.15 | CTIO/Chiron
56964.865 | 0.73 | 0.15 | CTIO/Chiron
56965.862 | 0.70 | 0.14 | CTIO/Chiron
56968.867 | 0.75 | 0.11 | CTIO/Chiron
56969.863 | 0.70 | 0.14 | CTIO/Chiron
56972.881 | 0.64 | 0.13 | CTIO/Chiron
56974.847 | 0.61 | 0.12 | CTIO/Chiron
56979.839 | 0.61 | 0.12 | CTIO/Chiron
56980.806 | 0.56 | 0.11 | CTIO/Chiron
56984.820 | 0.55 | 0.11 | CTIO/Chiron
56985.828 | 0.55 | 0.11 | CTIO/Chiron
56986.872 | 0.53 | 0.11 | CTIO/Chiron
56988.794 | 0.49 | 0.10 | CTIO/Chiron
56990.764 | 0.50 | 0.10 | CTIO/Chiron
56992.781 | 0.48 | 0.10 | CTIO/Chiron
56994.817 | 0.42 | 0.08 | CTIO/Chiron
56996.852 | 0.40 | 0.08 | CTIO/Chiron
56998.805 | 0.41 | 0.08 | CTIO/Chiron
57000.837 | 0.37 | 0.07 | CTIO/Chiron
57007.853 | 0.34 | 0.07 | CTIO/Chiron
57008.739 | 0.34 | 0.07 | CTIO/Chiron
57009.749 | 0.33 | 0.07 | CTIO/Chiron
57012.817 | 0.34 | 0.07 | CTIO/Chiron
57014.738 | 0.35 | 0.07 | CTIO/Chiron
57015.766 | 0.34 | 0.07 | CTIO/Chiron
57016.796 | 0.30 | 0.06 | CTIO/Chiron
57018.779 | 0.31 | 0.06 | CTIO/Chiron
57021.836 | 0.30 | 0.06 | CTIO/Chiron
57022.752 | 0.30 | 0.06 | CTIO/Chiron
57025.828 | 0.32 | 0.06 | CTIO/Chiron
57026.700 | 0.26 | 0.05 | CTIO/Chiron
57032.818 | 0.18 | 0.09 | CTIO/Chiron
57035.724 | 0.20 | 0.10 | CTIO/Chiron
57038.852 | 0.17 | 0.08 | CTIO/Chiron
57039.834 | 0.14 | 0.07 | CTIO/Chiron
57040.712 | 0.15 | 0.07 | CTIO/Chiron
57043.846 | 0.15 | 0.08 | CTIO/Chiron
57046.685 | 0.17 | 0.09 | CTIO/Chiron
57047.685 | 0.17 | 0.08 | CTIO/Chiron
57048.810 | 0.33 | 0.07 | CTIO/Chiron
57050.732 | 0.21 | 0.10 | CTIO/Chiron
57051.847 | 0.45 | 0.09 | CTIO/Chiron
57060.663 | 0.49 | 0.10 | CTIO/Chiron
57061.851 | 0.47 | 0.09 | CTIO/Chiron
57062.697 | 0.43 | 0.09 | CTIO/Chiron
57063.735 | 0.50 | 0.10 | CTIO/Chiron
57064.776 | 0.48 | 0.10 | CTIO/Chiron
57068.771 | 0.53 | 0.11 | CTIO/Chiron
57070.647 | 0.58 | 0.12 | CTIO/Chiron
57074.800 | 0.65 | 0.13 | CTIO/Chiron
57075.700 | 0.64 | 0.13 | CTIO/Chiron
57078.899 | 0.73 | 0.15 | CTIO/Chiron
57083.662 | 0.74 | 0.11 | CTIO/Chiron
57088.642 | 0.69 | 0.14 | CTIO/Chiron
57091.593 | 0.73 | 0.15 | CTIO/Chiron
57092.723 | 0.71 | 0.14 | CTIO/Chiron
57093.711 | 0.69 | 0.14 | CTIO/Chiron
57095.800 | 0.71 | 0.14 | CTIO/Chiron
57097.696 | 0.68 | 0.14 | CTIO/Chiron
57104.561 | 0.58 | 0.12 | CTIO/Chiron
57115.749 | 0.54 | 0.11 | CTIO/Chiron
57118.557 | 0.56 | 0.11 | CTIO/Chiron
57120.539 | 0.68 | 0.14 | CTIO/Chiron
57124.499 | 0.67 | 0.13 | CTIO/Chiron
57125.524 | 0.68 | 0.14 | CTIO/Chiron
57127.619 | 0.65 | 0.13 | CTIO/Chiron
57130.544 | 0.68 | 0.14 | CTIO/Chiron
57132.516 | 0.66 | 0.13 | CTIO/Chiron
57144.693 | 0.74 | 0.11 | CTIO/Chiron
57145.627 | 0.66 | 0.13 | CTIO/Chiron
57147.629 | 0.76 | 0.11 | CTIO/Chiron
57152.591 | 0.71 | 0.14 | CTIO/Chiron
57155.575 | 0.73 | 0.15 | CTIO/Chiron
57161.553 | 0.71 | 0.14 | CTIO/Chiron
57164.551 | 0.73 | 0.15 | CTIO/Chiron
57166.533 | 0.75 | 0.11 | CTIO/Chiron
57174.594 | 0.79 | 0.12 | CTIO/Chiron
57177.490 | 0.74 | 0.11 | CTIO/Chiron
57181.449 | 0.73 | 0.15 | CTIO/Chiron
57185.503 | 0.75 | 0.11 | CTIO/Chiron
57189.503 | 0.73 | 0.15 | CTIO/Chiron
57191.461 | 0.69 | 0.14 | CTIO/Chiron
57443.957 | 0.67 | 0.13 | SASER/TB
57887.486 | 0.83 | 0.13 | OPD/Coudé
58186.045 | 0.62 | 0.12 | SASER/PMG
58502.447 | 0.58 | 0.12 | LCOGT/NRES
58557.060 | 0.53 | 0.11 | SASER/PMG
58574.933 | 0.75 | 0.11 | SASER/DBH
58584.073 | 0.74 | 0.11 | SASER/PMG
58602.886 | 0.84 | 0.13 | SASER/PMG
58609.981 | 0.82 | 0.12 | SASER/PMG
58614.934 | 0.90 | 0.14 | SASER/DBH
58618.875 | 0.82 | 0.12 | SASER/DBH
58622.886 | 0.90 | 0.14 | SASER/DBH
58625.010 | 0.87 | 0.13 | SASER/PMG
58650.935 | 1.08 | 0.16 | SASER/DBH
58658.870 | 1.07 | 0.16 | SASER/DBH
58668.898 | 0.87 | 0.13 | SASER/PMG
58684.885 | 0.73 | 0.15 | SASER/PMG
58693.882 | 0.71 | 0.14 | SASER/PMG
58757.254 | 0.76 | 0.11 | SASER/PMG
58777.866 | 0.67 | 0.13 | CTIO/Chiron
58782.882 | 0.70 | 0.14 | CTIO/Chiron
58785.874 | 0.73 | 0.15 | CTIO/Chiron
58800.859 | 0.64 | 0.13 | CTIO/Chiron
58803.840 | 0.49 | 0.10 | CTIO/Chiron
58805.831 | 0.44 | 0.09 | CTIO/Chiron
58806.134 | 0.32 | 0.06 | SASER/PMG
58809.861 | 0.33 | 0.07 | CTIO/Chiron
58812.863 | 0.27 | 0.05 | CTIO/Chiron
58814.857 | 0.28 | 0.06 | CTIO/Chiron
58817.861 | 0.25 | 0.05 | CTIO/Chiron
58820.801 | 0.29 | 0.06 | LCOGT/NRES
58820.810 | 0.24 | 0.12 | CTIO/Chiron
58822.813 | 0.27 | 0.05 | CTIO/Chiron
58824.794 | 0.31 | 0.06 | CTIO/Chiron
58827.790 | 0.40 | 0.08 | LCOGT/NRES
58827.860 | 0.36 | 0.07 | CTIO/Chiron
58828.097 | 0.38 | 0.08 | SASER/PMG
58829.753 | 0.40 | 0.08 | LCOGT/NRES
58830.821 | 0.33 | 0.07 | CTIO/Chiron
58832.859 | 0.36 | 0.07 | CTIO/Chiron
58833.793 | 0.47 | 0.09 | LCOGT/NRES
58834.840 | 0.42 | 0.08 | CTIO/Chiron
58836.810 | 0.50 | 0.10 | LCOGT/NRES
58836.817 | 0.41 | 0.08 | CTIO/Chiron
58839.524 | 0.45 | 0.09 | LCOGT/NRES
58841.495 | 0.43 | 0.09 | LCOGT/NRES
58843.506 | 0.47 | 0.09 | LCOGT/NRES
58845.524 | 0.46 | 0.09 | LCOGT/NRES
58847.497 | 0.51 | 0.10 | LCOGT/NRES
58848.720 | 0.56 | 0.11 | LCOGT/NRES
58851.498 | 0.63 | 0.13 | LCOGT/NRES
58851.758 | 0.62 | 0.12 | LCOGT/NRES
58854.790 | 0.64 | 0.13 | LCOGT/NRES
58857.026 | 0.65 | 0.13 | SASER/PMG
58857.786 | 0.70 | 0.14 | LCOGT/NRES
58858.717 | 0.76 | 0.11 | LCOGT/NRES
58859.717 | 0.72 | 0.14 | LCOGT/NRES
58860.479 | 0.69 | 0.14 | LCOGT/NRES
58860.857 | 0.63 | 0.13 | LCOGT/NRES
58861.812 | 0.67 | 0.13 | LCOGT/NRES
58862.750 | 0.69 | 0.14 | LCOGT/NRES
58863.700 | 0.70 | 0.14 | LCOGT/NRES
58866.836 | 0.75 | 0.11 | LCOGT/NRES
58869.840 | 0.74 | 0.11 | LCOGT/NRES
58871.798 | 0.86 | 0.13 | LCOGT/NRES
58874.381 | 0.82 | 0.12 | LCOGT/NRES
58876.853 | 0.95 | 0.14 | LCOGT/NRES
58877.502 | 0.99 | 0.15 | LCOGT/NRES
58878.541 | 0.98 | 0.15 | LCOGT/NRES
58880.847 | 1.03 | 0.15 | LCOGT/NRES
58882.837 | 1.07 | 0.16 | LCOGT/NRES
58883.807 | 1.08 | 0.16 | LCOGT/NRES
58884.598 | 1.26 | 0.19 | LCOGT/NRES
58884.798 | 1.15 | 0.17 | LCOGT/NRES
58884.998 | 1.30 | 0.20 | SASER/PMG
58885.496 | 1.29 | 0.19 | LCOGT/NRES
58885.687 | 1.31 | 0.20 | LCOGT/NRES
58886.823 | 1.39 | 0.21 | LCOGT/NRES
58887.705 | 1.41 | 0.21 | LCOGT/NRES
58888.533 | 1.41 | 0.21 | LCOGT/NRES
58888.671 | 1.35 | 0.20 | LCOGT/NRES
58889.750 | 1.45 | 0.22 | LCOGT/NRES
58890.788 | 1.33 | 0.20 | LCOGT/NRES
58891.646 | 1.27 | 0.19 | LCOGT/NRES
58892.810 | 1.09 | 0.16 | LCOGT/NRES
58893.511 | 0.98 | 0.15 | LCOGT/NRES
58893.796 | 1.04 | 0.16 | LCOGT/NRES
58894.807 | 0.89 | 0.13 | LCOGT/NRES
58896.550 | 0.62 | 0.12 | LCOGT/NRES
58896.851 | 0.60 | 0.12 | LCOGT/NRES
58898.386 | 0.44 | 0.09 | LCOGT/NRES
58898.691 | 0.40 | 0.08 | LCOGT/NRES
58899.795 | 0.39 | 0.08 | LCOGT/NRES
58900.786 | 0.38 | 0.08 | LCOGT/NRES
58901.847 | 0.37 | 0.07 | LCOGT/NRES
58903.715 | 0.35 | 0.07 | LCOGT/NRES
58904.702 | 0.31 | 0.06 | LCOGT/NRES
58906.798 | 0.25 | 0.05 | LCOGT/NRES
58908.725 | 0.26 | 0.05 | LCOGT/NRES
58910.612 | 0.23 | 0.12 | LCOGT/NRES
58912.813 | 0.18 | 0.09 | LCOGT/NRES
58914.638 | 0.22 | 0.11 | LCOGT/NRES
58916.669 | 0.21 | 0.11 | LCOGT/NRES
58918.680 | 0.24 | 0.05 | LCOGT/NRES
58920.736 | 0.25 | 0.05 | LCOGT/NRES
58922.732 | 0.24 | 0.12 | LCOGT/NRES
58924.651 | 0.25 | 0.05 | LCOGT/NRES
58927.501 | 0.24 | 0.12 | LCOGT/NRES
58928.494 | 0.25 | 0.05 | LCOGT/NRES
58930.462 | 0.28 | 0.06 | LCOGT/NRES
58931.260 | 0.31 | 0.06 | LCOGT/NRES
58933.260 | 0.38 | 0.08 | LCOGT/NRES
58935.439 | 0.59 | 0.12 | SASER/DBH
58937.493 | 0.70 | 0.14 | SASER/PC
58939.495 | 0.58 | 0.12 | SASER/DBH
58944.427 | 0.60 | 0.12 | SASER/DBH
58947.947 | 0.75 | 0.11 | SASER/DBH
58948.886 | 0.64 | 0.13 | SASER/DBH
58948.903 | 0.70 | 0.14 | SASER/DBH
58955.988 | 0.83 | 0.12 | SASER/DBH
58958.375 | 0.82 | 0.12 | OPD/Coudé
58959.939 | 0.75 | 0.11 | SASER/DBH
58964.968 | 0.78 | 0.12 | SASER/TB
58985.375 | 0.80 | 0.12 | OPD/Coudé
58987.945 | 0.87 | 0.13 | SASER/DBH
58991.202 | 0.74 | 0.11 | LCOGT/NRES
59000.200 | 0.76 | 0.11 | LCOGT/NRES
59006.320 | 0.77 | 0.11 | LCOGT/NRES
59020.279 | 0.88 | 0.13 | LCOGT/NRES
59025.226 | 0.89 | 0.13 | LCOGT/NRES
59035.243 | 0.79 | 0.12 | LCOGT/NRES
59039.231 | 0.79 | 0.12 | LCOGT/NRES
59051.219 | 0.93 | 0.14 | LCOGT/NRES
59152.598 | 0.63 | 0.13 | LCOGT/NRES
59155.597 | 0.65 | 0.13 | LCOGT/NRES
59174.559 | 0.81 | 0.12 | LCOGT/NRES
59206.510 | 0.80 | 0.12 | LCOGT/NRES
59210.459 | 0.82 | 0.12 | LCOGT/NRES
59216.451 | 0.84 | 0.13 | LCOGT/NRES
59222.481 | 0.81 | 0.12 | LCOGT/NRES
59228.494 | 0.78 | 0.12 | LCOGT/NRES
59236.565 | 0.65 | 0.13 | LCOGT/NRES
59252.611 | 1.12 | 0.17 | LCOGT/NRES
59258.620 | 1.33 | 0.20 | LCOGT/NRES
59265.552 | 1.44 | 0.22 | LCOGT/NRES
59277.447 | 1.38 | 0.21 | LCOGT/NRES
59290.389 | 1.26 | 0.19 | LCOGT/NRES
59304.434 | 1.00 | 0.15 | LCOGT/NRES
59305.302 | 1.01 | 0.15 | LCOGT/NRES
59322.344 | 0.87 | 0.13 | LCOGT/NRES
59337.432 | 0.85 | 0.13 | LCOGT/NRES
59359.382 | 0.91 | 0.14 | LCOGT/NRES
59379.274 | 0.86 | 0.13 | LCOGT/NRES
59406.205 | 0.86 | 0.13 | LCOGT/NRES
59697.976 | 1.13 | 0.12 | SASER/BH

Table 5: Equivalent widths of the 6347 Å absorption feature. HJD | EW 6347 | $\sigma_{\rm{EW}}$ | Facility
---|---|---|---
| ((Å)) | ((Å)) |
47918.500 | 0.16 | 0.03 | OPD/Coudé
48780.500 | 0.01 | 0.00 | OPD/Coudé
48793.990 | 0.94 | 0.19 | OPD/Coudé
48798.500 | 0.77 | 0.15 | OPD/Coudé
48825.010 | 0.04 | 0.01 | OPD/Coudé
48830.010 | 0.03 | 0.01 | OPD/Coudé
48838.300 | 0.01 | 0.00 | OPD/Coudé
48843.990 | 0.02 | 0.00 | OPD/Coudé
49063.100 | 0.12 | 0.02 | OPD/Coudé
49063.109 | 0.11 | 0.02 | ESO/FEROS
49065.109 | 0.14 | 0.03 | ESO/FEROS
49066.120 | 0.13 | 0.03 | ESO/FEROS
49067.100 | 0.10 | 0.02 | ESO/FEROS
49068.100 | 0.13 | 0.03 | ESO/FEROS
49069.100 | 0.11 | 0.02 | ESO/FEROS
49070.100 | 0.09 | 0.02 | ESO/FEROS
49071.110 | 0.09 | 0.02 | ESO/FEROS
49072.110 | 0.10 | 0.02 | ESO/FEROS
49073.140 | 0.08 | 0.02 | ESO/FEROS
49074.120 | 0.08 | 0.02 | ESO/FEROS
49075.070 | 0.07 | 0.01 | ESO/FEROS
49076.120 | 0.10 | 0.02 | ESO/FEROS
49077.080 | 0.08 | 0.02 | ESO/FEROS
49078.110 | 0.07 | 0.01 | ESO/FEROS
49079.100 | 0.08 | 0.02 | ESO/FEROS
49080.100 | 0.08 | 0.02 | ESO/FEROS
49081.100 | 0.07 | 0.01 | ESO/FEROS
49082.100 | 0.08 | 0.02 | ESO/FEROS
49083.090 | 0.08 | 0.02 | ESO/FEROS
49084.090 | 0.08 | 0.02 | ESO/FEROS
49085.090 | 0.05 | 0.01 | ESO/FEROS
49086.100 | 0.07 | 0.01 | ESO/FEROS
49087.100 | 0.08 | 0.02 | ESO/FEROS
49088.100 | 0.10 | 0.02 | ESO/FEROS
49089.120 | 0.11 | 0.02 | ESO/FEROS
49089.120 | 0.10 | 0.02 | ESO/FEROS
49090.100 | 0.09 | 0.02 | ESO/FEROS
49091.120 | 0.15 | 0.03 | ESO/FEROS
49095.080 | 0.13 | 0.03 | ESO/FEROS
49098.120 | 0.15 | 0.03 | ESO/FEROS
49098.180 | 0.15 | 0.03 | ESO/FEROS
49100.100 | 0.15 | 0.03 | ESO/FEROS
49101.100 | 0.16 | 0.03 | ESO/FEROS
49102.100 | 0.16 | 0.03 | ESO/FEROS
49103.100 | 0.15 | 0.03 | ESO/FEROS
49103.230 | 0.14 | 0.03 | ESO/FEROS
49104.110 | 0.13 | 0.03 | ESO/FEROS
49105.100 | 0.15 | 0.03 | ESO/FEROS
49106.100 | 0.17 | 0.03 | ESO/FEROS
49107.100 | 0.14 | 0.03 | ESO/FEROS
49108.100 | 0.13 | 0.03 | ESO/FEROS
49109.100 | 0.13 | 0.03 | ESO/FEROS
49110.180 | 0.14 | 0.03 | ESO/FEROS
49110.180 | 0.06 | 0.01 | ESO/FEROS
49111.180 | 0.17 | 0.03 | ESO/FEROS
49112.170 | 0.11 | 0.02 | ESO/FEROS
49113.070 | 0.12 | 0.02 | ESO/FEROS
49114.170 | 0.16 | 0.03 | ESO/FEROS
49118.060 | 0.11 | 0.02 | ESO/FEROS
49120.170 | 0.08 | 0.02 | ESO/FEROS
49121.050 | 0.08 | 0.02 | ESO/FEROS
49122.020 | 0.11 | 0.02 | ESO/FEROS
49123.130 | 0.07 | 0.01 | ESO/FEROS
49124.030 | 0.08 | 0.02 | ESO/FEROS
49125.030 | 0.05 | 0.01 | ESO/FEROS
49127.110 | 0.09 | 0.02 | ESO/FEROS
49128.030 | 0.06 | 0.01 | ESO/FEROS
49129.040 | 0.06 | 0.01 | ESO/FEROS
49130.040 | 0.06 | 0.01 | ESO/FEROS
49132.040 | 0.05 | 0.01 | ESO/FEROS
49134.120 | 0.03 | 0.01 | ESO/FEROS
49135.120 | 0.03 | 0.01 | ESO/FEROS
49137.144 | 0.06 | 0.01 | ESO/FEROS
49138.080 | 0.02 | 0.00 | ESO/FEROS
49139.140 | 0.03 | 0.01 | ESO/FEROS
49395.370 | 0.09 | 0.02 | ESO/FEROS
49408.030 | 0.10 | 0.02 | ESO/FEROS
49424.020 | 0.17 | 0.03 | ESO/FEROS
49448.100 | 0.22 | 0.04 | ESO/FEROS
49472.100 | 0.28 | 0.06 | ESO/FEROS
49514.040 | 0.30 | 0.06 | ESO/FEROS
49520.110 | 0.30 | 0.06 | ESO/FEROS
49522.040 | 0.31 | 0.06 | ESO/FEROS
49525.030 | 0.36 | 0.07 | ESO/FEROS
49530.410 | 0.37 | 0.07 | ESO/FEROS
49532.040 | 0.38 | 0.08 | ESO/FEROS
49534.000 | 0.38 | 0.08 | ESO/FEROS
49549.410 | 0.44 | 0.09 | ESO/FEROS
49727.000 | 0.25 | 0.05 | ESO/FEROS
49751.220 | 0.18 | 0.04 | OPD/Coudé
49770.240 | 0.09 | 0.02 | OPD/Coudé
49786.120 | 0.06 | 0.01 | OPD/Coudé
49786.500 | 0.13 | 0.03 | OPD/Coudé
49800.240 | 0.10 | 0.02 | OPD/Coudé
49821.230 | 0.16 | 0.03 | OPD/Coudé
49836.050 | 0.11 | 0.02 | OPD/Coudé
49846.040 | 0.09 | 0.02 | OPD/Coudé
49860.070 | 0.05 | 0.01 | OPD/Coudé
49861.410 | 0.08 | 0.02 | OPD/Coudé
50120.280 | 0.09 | 0.02 | ESO/FEROS
50794.500 | 0.01 | 0.00 | ESO/FEROS
50804.260 | 0.07 | 0.01 | ESO/FEROS
50833.400 | 0.55 | 0.11 | ESO/FEROS
50834.500 | 0.52 | 0.10 | ESO/FEROS
50843.220 | 0.44 | 0.09 | ESO/FEROS
50847.300 | 0.37 | 0.07 | ESO/FEROS
50878.120 | 0.24 | 0.05 | ESO/FEROS
50892.150 | 0.17 | 0.03 | ESO/FEROS
50919.300 | 0.20 | 0.04 | ESO/FEROS
50942.300 | 0.34 | 0.07 | ESO/FEROS
51004.500 | 0.26 | 0.05 | ESO/FEROS
51131.323 | 0.33 | 0.07 | ESO/FEROS
51135.320 | 0.34 | 0.07 | ESO/FEROS
51142.320 | 0.30 | 0.06 | ESO/FEROS
51148.320 | 0.27 | 0.05 | ESO/FEROS
51150.350 | 0.29 | 0.06 | ESO/FEROS
51154.370 | 0.30 | 0.06 | ESO/FEROS
51155.370 | 0.29 | 0.06 | ESO/FEROS
51156.370 | 0.28 | 0.06 | ESO/FEROS
51173.225 | 0.32 | 0.06 | ESO/FEROS
51175.225 | 0.32 | 0.06 | ESO/FEROS
51178.370 | 0.34 | 0.07 | ESO/FEROS
51181.380 | 0.35 | 0.07 | ESO/FEROS
51183.383 | 0.32 | 0.06 | ESO/FEROS
51187.383 | 0.37 | 0.07 | ESO/FEROS
51196.396 | 0.37 | 0.07 | ESO/FEROS
51226.500 | 0.32 | 0.06 | ESO/FEROS
51231.070 | 0.39 | 0.08 | ESO/FEROS
51247.180 | 0.27 | 0.05 | ESO/FEROS
51291.069 | 0.24 | 0.05 | ESO/FEROS
51291.075 | 0.24 | 0.05 | ESO/FEROS
51530.299 | 0.48 | 0.10 | OPD/Coudé
51532.352 | 0.47 | 0.09 | OPD/Coudé
51533.293 | 0.46 | 0.09 | ESO/UVES
51594.400 | 0.41 | 0.08 | ESO/FEROS
51654.049 | 0.46 | 0.09 | ESO/FEROS
52017.330 | 0.50 | 0.10 | ESO/FEROS
52067.000 | 0.34 | 0.07 | ESO/FEROS
52067.500 | 0.38 | 0.08 | ESO/FEROS
52068.500 | 0.35 | 0.07 | ESO/FEROS
52075.885 | 0.36 | 0.07 | ESO/FEROS
52077.500 | 0.38 | 0.08 | ESO/FEROS
52294.600 | 0.17 | 0.03 | ESO/FEROS
52301.190 | 0.19 | 0.04 | ESO/FEROS
52458.980 | 0.22 | 0.04 | ESO/FEROS
52459.500 | 0.21 | 0.04 | ESO/FEROS
52460.160 | 0.21 | 0.04 | ESO/FEROS
52615.311 | 0.08 | 0.02 | ESO/UVES
52620.344 | 0.09 | 0.02 | ESO/UVES
52683.390 | 0.10 | 0.02 | OPD/Coudé
52684.128 | 0.06 | 0.01 | ESO/UVES
52713.500 | 0.01 | 0.00 | ESO/FEROS
52734.500 | 0.02 | 0.00 | ESO/FEROS
52773.500 | 0.01 | 0.00 | ESO/FEROS
52777.120 | 0.01 | 0.00 | ESO/FEROS
52788.063 | 0.00 | 0.00 | ESO/UVES
52789.500 | 0.02 | 0.00 | ESO/FEROS
52792.460 | 0.01 | 0.00 | ESO/FEROS
52793.986 | 0.00 | 0.00 | ESO/UVES
52808.000 | 0.03 | 0.01 | ESO/FEROS
52811.500 | 0.04 | 0.01 | ESO/FEROS
52812.500 | 0.04 | 0.01 | ESO/FEROS
52812.730 | 0.07 | 0.01 | ESO/FEROS
52813.500 | 0.07 | 0.01 | ESO/FEROS
52814.500 | 0.09 | 0.02 | ESO/FEROS
52815.500 | 0.11 | 0.02 | ESO/FEROS
52816.500 | 0.14 | 0.03 | ESO/FEROS
52817.500 | 0.19 | 0.04 | ESO/FEROS
52818.500 | 0.23 | 0.05 | ESO/FEROS
52820.500 | 0.34 | 0.07 | ESO/FEROS
52821.500 | 0.41 | 0.08 | ESO/FEROS
52822.500 | 0.56 | 0.11 | ESO/FEROS
52823.500 | 0.70 | 0.14 | ESO/FEROS
52824.500 | 0.79 | 0.16 | ESO/FEROS
52825.005 | 0.84 | 0.17 | ESO/UVES
52826.500 | 0.90 | 0.18 | ESO/FEROS
52829.410 | 1.01 | 0.20 | ESO/FEROS
52840.500 | 1.20 | 0.24 | ESO/FEROS
52852.470 | 1.12 | 0.22 | ESO/FEROS
52867.500 | 0.99 | 0.20 | ESO/FEROS
52904.980 | 0.60 | 0.12 | ESO/FEROS
52985.500 | 0.38 | 0.08 | ESO/FEROS
52987.500 | 0.37 | 0.07 | ESO/FEROS
53049.500 | 0.28 | 0.06 | ESO/FEROS
53053.000 | 0.24 | 0.05 | ESO/FEROS
53054.500 | 0.26 | 0.05 | ESO/FEROS
53055.127 | 0.21 | 0.04 | ESO/UVES
53066.500 | 0.22 | 0.04 | OPD/Coudé
53071.840 | 0.38 | 0.08 | OPD/Coudé
53413.381 | 0.50 | 0.10 | ESO/UVES
53448.134 | 0.39 | 0.08 | ESO/UVES
53453.500 | 0.39 | 0.08 | ESO/FEROS
53454.500 | 0.38 | 0.08 | ESO/FEROS
53579.000 | 0.38 | 0.08 | ESO/FEROS
53580.500 | 0.37 | 0.07 | ESO/FEROS
53718.000 | 0.71 | 0.14 | ESO/FEROS
53718.500 | 0.60 | 0.12 | ESO/FEROS
53720.500 | 0.63 | 0.13 | ESO/FEROS
53834.108 | 0.56 | 0.11 | ESO/UVES
53894.014 | 0.60 | 0.12 | ESO/UVES
53923.500 | 0.41 | 0.08 | ESO/FEROS
53924.500 | 0.39 | 0.08 | ESO/FEROS
54190.000 | 0.18 | 0.04 | OPD/Coudé
54190.530 | 0.17 | 0.03 | OPD/Coudé
54190.540 | 0.16 | 0.03 | OPD/Coudé
54278.000 | 0.19 | 0.04 | ESO/FEROS
54278.490 | 0.20 | 0.04 | ESO/FEROS
54280.950 | 0.21 | 0.04 | Gemini S/GMOS
54475.262 | 0.10 | 0.02 | ESO/UVES
54510.130 | 0.13 | 0.03 | Gemini S/GMOS
54513.301 | 0.18 | 0.04 | ESO/UVES
54517.215 | 0.14 | 0.03 | ESO/UVES
54535.231 | 0.14 | 0.03 | ESO/UVES
54535.269 | 0.13 | 0.03 | ESO/UVES
54554.276 | 0.09 | 0.02 | ESO/UVES
54567.011 | 0.10 | 0.02 | ESO/UVES
54583.017 | 0.18 | 0.04 | ESO/UVES
54598.968 | 0.13 | 0.03 | ESO/UVES
54601.420 | 0.11 | 0.02 | ESO/FEROS
54601.430 | 0.09 | 0.02 | ESO/FEROS
54616.029 | 0.09 | 0.02 | ESO/UVES
54617.096 | 0.08 | 0.02 | ESO/UVES
54620.960 | 0.08 | 0.02 | Gemini S/GMOS
54628.982 | 0.10 | 0.02 | ESO/UVES
54652.990 | 0.10 | 0.02 | Gemini S/GMOS
54656.028 | 0.08 | 0.02 | ESO/UVES
54755.864 | 0.01 | 0.00 | CTIO/Chiron
54779.280 | 0.00 | 0.00 | Gemini S/GMOS
54784.860 | 0.00 | 0.00 | CTIO/Chiron
54798.280 | 0.00 | 0.00 | Gemini S/GMOS
54816.845 | 0.00 | 0.00 | CTIO/Chiron
54818.807 | 0.01 | 0.00 | CTIO/Chiron
54819.290 | 0.00 | 0.00 | Gemini S/GMOS
54819.812 | 0.01 | 0.00 | CTIO/Chiron
54821.330 | 0.00 | 0.00 | ESO/FEROS
54821.853 | 0.01 | 0.00 | CTIO/Chiron
54822.370 | 0.00 | 0.00 | ESO/FEROS
54823.802 | 0.01 | 0.00 | CTIO/Chiron
54824.300 | 0.00 | 0.00 | ESO/FEROS
54824.755 | 0.00 | 0.00 | CTIO/Chiron
54826.300 | 0.00 | 0.00 | Gemini S/GMOS
54828.300 | 0.00 | 0.00 | ESO/FEROS
54829.785 | 0.00 | 0.00 | CTIO/Chiron
54830.300 | 0.00 | 0.00 | ESO/FEROS
54831.754 | 0.01 | 0.00 | CTIO/Chiron
54832.300 | 0.00 | 0.00 | ESO/FEROS
54832.300 | 0.00 | 0.00 | Gemini S/GMOS
54834.300 | 0.00 | 0.00 | ESO/FEROS
54835.270 | 0.00 | 0.00 | Gemini S/GMOS
54836.739 | 0.01 | 0.00 | CTIO/Chiron
54836.752 | 0.01 | 0.00 | CTIO/Chiron
54837.733 | 0.00 | 0.00 | CTIO/Chiron
54838.758 | 0.01 | 0.00 | CTIO/Chiron
54839.788 | 0.00 | 0.00 | CTIO/Chiron
54840.180 | 0.02 | 0.00 | Gemini S/GMOS
54840.780 | 0.02 | 0.00 | CTIO/Chiron
54841.360 | 0.03 | 0.01 | ESO/UVES
54842.775 | 0.07 | 0.01 | CTIO/Chiron
54843.280 | 0.14 | 0.03 | Gemini S/GMOS
54843.740 | 0.16 | 0.03 | OPD/Coudé
54843.774 | 0.13 | 0.03 | CTIO/Chiron
54844.750 | 0.19 | 0.04 | OPD/Coudé
54844.777 | 0.27 | 0.05 | CTIO/Chiron
54845.766 | 0.29 | 0.06 | CTIO/Chiron
54845.850 | 0.25 | 0.05 | OPD/Coudé
54845.850 | 0.23 | 0.05 | OPD/Coudé
54846.180 | 0.44 | 0.09 | Gemini S/GMOS
54846.771 | 0.58 | 0.12 | CTIO/Chiron
54848.741 | 0.75 | 0.15 | CTIO/Chiron
54849.726 | 0.78 | 0.16 | CTIO/Chiron
54850.734 | 0.80 | 0.16 | CTIO/Chiron
54851.700 | 0.82 | 0.16 | OPD/Coudé
54851.719 | 0.84 | 0.17 | CTIO/Chiron
54851.720 | 0.85 | 0.17 | OPD/Coudé
54852.742 | 0.86 | 0.17 | CTIO/Chiron
54853.280 | 0.83 | 0.17 | Gemini S/GMOS
54853.729 | 0.80 | 0.16 | CTIO/Chiron
54854.740 | 0.90 | 0.18 | CTIO/Chiron
54855.320 | 0.86 | 0.17 | Gemini S/GMOS
54855.736 | 0.80 | 0.16 | CTIO/Chiron
54857.786 | 0.79 | 0.16 | CTIO/Chiron
54858.768 | 0.78 | 0.16 | CTIO/Chiron
54859.775 | 0.78 | 0.16 | CTIO/Chiron
54860.300 | 0.84 | 0.17 | Gemini S/GMOS
54861.726 | 0.76 | 0.15 | CTIO/Chiron
54862.739 | 0.81 | 0.16 | CTIO/Chiron
54863.759 | 0.73 | 0.15 | CTIO/Chiron
54864.728 | 0.74 | 0.15 | CTIO/Chiron
54866.716 | 0.75 | 0.15 | CTIO/Chiron
54867.200 | 0.72 | 0.14 | Gemini S/GMOS
54867.249 | 0.74 | 0.15 | ESO/UVES
54867.707 | 0.75 | 0.15 | CTIO/Chiron
54871.700 | 0.65 | 0.13 | OPD/Coudé
54871.720 | 0.65 | 0.13 | OPD/Coudé
54874.730 | 0.58 | 0.12 | OPD/Coudé
54874.730 | 0.58 | 0.12 | OPD/Coudé
54875.651 | 0.58 | 0.12 | CTIO/Chiron
54877.720 | 0.44 | 0.09 | OPD/Coudé
54879.660 | 0.47 | 0.09 | CTIO/Chiron
54881.200 | 0.40 | 0.08 | Gemini S/GMOS
54882.660 | 0.37 | 0.07 | OPD/Coudé
54883.680 | 0.35 | 0.07 | OPD/Coudé
54887.680 | 0.37 | 0.07 | OPD/Coudé
54891.680 | 0.42 | 0.08 | OPD/Coudé
54896.710 | 0.39 | 0.08 | OPD/Coudé
54907.260 | 0.40 | 0.08 | Gemini S/GMOS
54923.242 | 0.40 | 0.08 | ESO/UVES
54940.000 | 0.43 | 0.09 | OPD/Coudé
54940.600 | 0.43 | 0.09 | OPD/Coudé
54946.078 | 0.41 | 0.08 | ESO/UVES
54949.040 | 0.40 | 0.08 | Gemini S/GMOS
54953.100 | 0.45 | 0.09 | ESO/FEROS
54953.102 | 0.46 | 0.09 | ESO/FEROS
54955.085 | 0.46 | 0.09 | ESO/FEROS
54955.087 | 0.46 | 0.09 | ESO/FEROS
54955.088 | 0.46 | 0.09 | ESO/FEROS
54987.000 | 0.41 | 0.08 | OPD/Coudé
54987.410 | 0.46 | 0.09 | OPD/Coudé
55035.970 | 0.39 | 0.08 | Gemini S/GMOS
55125.873 | 0.31 | 0.06 | CTIO/Chiron
55139.848 | 0.36 | 0.07 | CTIO/Chiron
55140.829 | 0.36 | 0.07 | CTIO/Chiron
55164.815 | 0.33 | 0.07 | CTIO/Chiron
55172.210 | 0.50 | 0.10 | OPD/Coudé
55204.300 | 0.38 | 0.08 | Gemini S/GMOS
55207.708 | 0.43 | 0.09 | CTIO/Chiron
55213.760 | 0.41 | 0.08 | CTIO/Chiron
55226.741 | 0.52 | 0.10 | CTIO/Chiron
55230.625 | 0.46 | 0.09 | CTIO/Chiron
55240.647 | 0.48 | 0.10 | CTIO/Chiron
55250.614 | 0.53 | 0.11 | CTIO/Chiron
55254.575 | 0.53 | 0.11 | CTIO/Chiron
55259.603 | 0.59 | 0.12 | CTIO/Chiron
55270.555 | 0.47 | 0.09 | CTIO/Chiron
55278.497 | 0.47 | 0.09 | CTIO/Chiron
55284.533 | 0.57 | 0.11 | CTIO/Chiron
55293.508 | 0.64 | 0.13 | CTIO/Chiron
55306.499 | 0.67 | 0.13 | CTIO/Chiron
55311.518 | 0.71 | 0.14 | CTIO/Chiron
55314.595 | 0.64 | 0.13 | CTIO/Chiron
55317.485 | 0.69 | 0.14 | CTIO/Chiron
55327.461 | 0.79 | 0.16 | CTIO/Chiron
55335.474 | 0.75 | 0.15 | CTIO/Chiron
55360.374 | 0.72 | 0.14 | CTIO/Chiron
55735.000 | 0.41 | 0.08 | OPD/Coudé
55754.000 | 0.46 | 0.09 | OPD/Coudé
55755.400 | 0.44 | 0.09 | OPD/Coudé
55755.402 | 0.41 | 0.08 | OPD/Coudé
55960.000 | 0.43 | 0.09 | OPD/Coudé
55989.692 | 0.49 | 0.10 | CTIO/Chiron
55993.755 | 0.50 | 0.10 | CTIO/Chiron
56001.729 | 0.46 | 0.09 | CTIO/Chiron
56013.689 | 0.40 | 0.08 | CTIO/Chiron
56098.108 | 0.40 | 0.08 | ESO/FEROS
56221.888 | 0.40 | 0.08 | CTIO/Chiron
56236.844 | 0.40 | 0.08 | CTIO/Chiron
56238.867 | 0.45 | 0.09 | CTIO/Chiron
56248.812 | 0.46 | 0.09 | CTIO/Chiron
56254.880 | 0.48 | 0.10 | CTIO/Chiron
56260.781 | 0.46 | 0.09 | CTIO/Chiron
56275.818 | 0.55 | 0.11 | CTIO/Chiron
56289.797 | 0.51 | 0.10 | CTIO/Chiron
56361.647 | 0.43 | 0.09 | CTIO/Chiron
56401.591 | 0.43 | 0.09 | CTIO/Chiron
56417.592 | 0.42 | 0.08 | CTIO/Chiron
56607.843 | 0.22 | 0.04 | CTIO/Chiron
56612.865 | 0.18 | 0.04 | CTIO/Chiron
56621.282 | 0.19 | 0.04 | ESO/UVES
56621.282 | 0.21 | 0.04 | ESO/UVES
56650.347 | 0.23 | 0.05 | ESO/UVES
56656.703 | 0.23 | 0.05 | CTIO/Chiron
56659.709 | 0.20 | 0.04 | CTIO/Chiron
56664.675 | 0.18 | 0.04 | CTIO/Chiron
56670.783 | 0.13 | 0.03 | CTIO/Chiron
56672.838 | 0.14 | 0.03 | CTIO/Chiron
56677.760 | 0.12 | 0.02 | CTIO/Chiron
56684.200 | 0.09 | 0.02 | ESO/UVES
56684.201 | 0.08 | 0.02 | ESO/UVES
56687.709 | 0.06 | 0.01 | CTIO/Chiron
56690.692 | 0.05 | 0.01 | CTIO/Chiron
56697.727 | 0.02 | 0.00 | CTIO/Chiron
56710.670 | 0.04 | 0.01 | CTIO/Chiron
56712.165 | 0.05 | 0.01 | ESO/UVES
56712.166 | 0.05 | 0.01 | ESO/UVES
56712.694 | 0.07 | 0.01 | CTIO/Chiron
56718.712 | 0.05 | 0.01 | CTIO/Chiron
56725.571 | 0.06 | 0.01 | CTIO/Chiron
56729.562 | 0.07 | 0.01 | CTIO/Chiron
56732.606 | 0.07 | 0.01 | CTIO/Chiron
56737.143 | 0.06 | 0.01 | ESO/UVES
56737.144 | 0.05 | 0.01 | ESO/UVES
56739.549 | 0.07 | 0.01 | CTIO/Chiron
56746.520 | 0.04 | 0.01 | CTIO/Chiron
56750.542 | 0.03 | 0.01 | CTIO/Chiron
56754.554 | 0.02 | 0.00 | CTIO/Chiron
56762.997 | 0.00 | 0.00 | ESO/UVES
56762.997 | 0.00 | 0.00 | ESO/UVES
56765.590 | 0.01 | 0.00 | CTIO/Chiron
56766.546 | 0.01 | 0.00 | CTIO/Chiron
56767.512 | 0.01 | 0.00 | CTIO/Chiron
56774.547 | 0.01 | 0.00 | CTIO/Chiron
56781.474 | 0.03 | 0.01 | CTIO/Chiron
56784.800 | 0.03 | 0.01 | MJUO/Hercules
56786.800 | 0.02 | 0.00 | MJUO/Hercules
56787.800 | 0.02 | 0.00 | MJUO/Hercules
56791.553 | 0.02 | 0.00 | CTIO/Chiron
56795.509 | 0.02 | 0.00 | CTIO/Chiron
56800.464 | 0.00 | 0.00 | CTIO/Chiron
56801.500 | 0.00 | 0.00 | CTIO/Chiron
56802.999 | 0.02 | 0.00 | ESO/UVES
56803.000 | 0.02 | 0.00 | ESO/UVES
56803.049 | 0.01 | 0.00 | ESO/UVES
56803.049 | 0.01 | 0.00 | ESO/UVES
56803.107 | 0.02 | 0.00 | ESO/UVES
56803.529 | 0.01 | 0.00 | CTIO/Chiron
56803.976 | 0.03 | 0.01 | ESO/UVES
56803.976 | 0.02 | 0.00 | ESO/UVES
56810.484 | 0.01 | 0.00 | CTIO/Chiron
56818.506 | 0.00 | 0.00 | CTIO/Chiron
56819.529 | 0.00 | 0.00 | CTIO/Chiron
56821.800 | 0.00 | 0.00 | MJUO/Hercules
56823.540 | 0.00 | 0.00 | CTIO/Chiron
56823.800 | 0.00 | 0.00 | MJUO/Hercules
56824.518 | 0.00 | 0.00 | CTIO/Chiron
56826.030 | 0.00 | 0.00 | ESO/UVES
56826.030 | 0.00 | 0.00 | ESO/UVES
56826.800 | 0.00 | 0.00 | MJUO/Hercules
56827.800 | 0.00 | 0.00 | MJUO/Hercules
56829.503 | 0.00 | 0.00 | CTIO/Chiron
56832.502 | 0.00 | 0.00 | CTIO/Chiron
56835.535 | 0.00 | 0.00 | CTIO/Chiron
56836.498 | 0.00 | 0.00 | CTIO/Chiron
56839.983 | 0.00 | 0.00 | ESO/UVES
56839.984 | 0.00 | 0.00 | ESO/UVES
56845.462 | 0.00 | 0.00 | CTIO/Chiron
56850.510 | 0.00 | 0.00 | CTIO/Chiron
56854.800 | 0.00 | 0.00 | MJUO/Hercules
56855.458 | 0.00 | 0.00 | CTIO/Chiron
56857.453 | 0.00 | 0.00 | CTIO/Chiron
56858.452 | 0.00 | 0.00 | CTIO/Chiron
56859.465 | 0.00 | 0.00 | CTIO/Chiron
56860.994 | 0.00 | 0.00 | ESO/UVES
56860.995 | 0.00 | 0.00 | ESO/UVES
56863.465 | 0.03 | 0.01 | CTIO/Chiron
56864.467 | 0.09 | 0.02 | CTIO/Chiron
56866.511 | 0.21 | 0.04 | CTIO/Chiron
56867.464 | 0.35 | 0.07 | CTIO/Chiron
56867.800 | 0.43 | 0.09 | MJUO/Hercules
56867.987 | 0.47 | 0.09 | ESO/UVES
56867.988 | 0.48 | 0.10 | ESO/UVES
56869.493 | 0.53 | 0.11 | CTIO/Chiron
56869.800 | 0.57 | 0.11 | MJUO/Hercules
56870.455 | 0.59 | 0.12 | CTIO/Chiron
56871.463 | 0.69 | 0.14 | CTIO/Chiron
56872.463 | 0.76 | 0.15 | CTIO/Chiron
56873.463 | 0.86 | 0.17 | CTIO/Chiron
56874.000 | 0.90 | 0.18 | OPD/Coudé
56874.454 | 0.92 | 0.18 | CTIO/Chiron
56876.458 | 1.03 | 0.21 | CTIO/Chiron
56878.482 | 0.94 | 0.19 | CTIO/Chiron
56879.466 | 0.95 | 0.19 | CTIO/Chiron
56880.466 | 0.97 | 0.19 | CTIO/Chiron
56881.465 | 0.93 | 0.19 | CTIO/Chiron
56882.461 | 0.94 | 0.19 | CTIO/Chiron
56883.465 | 0.92 | 0.18 | CTIO/Chiron
56883.800 | 0.92 | 0.18 | MJUO/Hercules
56885.462 | 0.86 | 0.17 | CTIO/Chiron
56886.469 | 0.80 | 0.16 | CTIO/Chiron
56887.460 | 0.73 | 0.15 | CTIO/SMARTS
56895.800 | 0.62 | 0.12 | MJUO/Hercules
56896.800 | 0.57 | 0.11 | MJUO/Hercules
56897.800 | 0.51 | 0.10 | MJUO/Hercules
56898.800 | 0.47 | 0.09 | MJUO/Hercules
56899.800 | 0.43 | 0.09 | MJUO/Hercules
56900.800 | 0.37 | 0.07 | MJUO/Hercules
56901.800 | 0.33 | 0.07 | MJUO/Hercules
56902.800 | 0.32 | 0.06 | MJUO/Hercules
56903.800 | 0.27 | 0.05 | MJUO/Hercules
56904.800 | 0.26 | 0.05 | MJUO/Hercules
56905.800 | 0.25 | 0.05 | MJUO/Hercules
56906.800 | 0.23 | 0.05 | MJUO/Hercules
56907.800 | 0.22 | 0.04 | MJUO/Hercules
56908.800 | 0.21 | 0.04 | MJUO/Hercules
56941.907 | 0.13 | 0.03 | CTIO/SMARTS
56942.373 | 0.24 | 0.05 | ESO/UVES
56942.374 | 0.22 | 0.04 | ESO/UVES
56942.907 | 0.16 | 0.03 | CTIO/SMARTS
56943.904 | 0.17 | 0.03 | CTIO/SMARTS
56944.897 | 0.18 | 0.04 | CTIO/SMARTS
56950.875 | 0.16 | 0.03 | CTIO/SMARTS
56951.873 | 0.19 | 0.04 | CTIO/SMARTS
56952.865 | 0.20 | 0.04 | CTIO/SMARTS
56953.880 | 0.20 | 0.04 | CTIO/SMARTS
56954.371 | 0.24 | 0.05 | ESO/UVES
56954.372 | 0.24 | 0.05 | ESO/UVES
56954.831 | 0.19 | 0.04 | CTIO/SMARTS
56955.861 | 0.22 | 0.04 | CTIO/SMARTS
56956.874 | 0.19 | 0.04 | CTIO/SMARTS
56957.890 | 0.21 | 0.04 | CTIO/SMARTS
56958.864 | 0.22 | 0.04 | CTIO/SMARTS
56959.847 | 0.20 | 0.04 | CTIO/SMARTS
56961.848 | 0.21 | 0.04 | CTIO/SMARTS
56964.865 | 0.25 | 0.05 | CTIO/SMARTS
56965.862 | 0.22 | 0.04 | CTIO/SMARTS
56968.867 | 0.25 | 0.05 | CTIO/SMARTS
56969.863 | 0.24 | 0.05 | CTIO/SMARTS
56972.881 | 0.25 | 0.05 | CTIO/SMARTS
56974.847 | 0.31 | 0.06 | CTIO/SMARTS
56977.323 | 0.33 | 0.07 | ESO/UVES
56977.323 | 0.33 | 0.07 | ESO/UVES
56977.846 | 0.30 | 0.06 | CTIO/SMARTS
56979.839 | 0.29 | 0.06 | CTIO/SMARTS
56980.806 | 0.30 | 0.06 | CTIO/SMARTS
56982.813 | 0.29 | 0.06 | CTIO/SMARTS
56984.820 | 0.29 | 0.06 | CTIO/SMARTS
56985.828 | 0.27 | 0.05 | CTIO/SMARTS
56986.872 | 0.28 | 0.06 | CTIO/SMARTS
56988.794 | 0.28 | 0.06 | CTIO/SMARTS
56990.764 | 0.30 | 0.06 | CTIO/SMARTS
56992.781 | 0.31 | 0.06 | CTIO/SMARTS
56994.817 | 0.33 | 0.07 | CTIO/SMARTS
56996.852 | 0.38 | 0.08 | CTIO/SMARTS
56998.805 | 0.34 | 0.07 | CTIO/SMARTS
57000.837 | 0.37 | 0.07 | CTIO/SMARTS
57007.853 | 0.41 | 0.08 | CTIO/Chiron
57008.739 | 0.40 | 0.08 | CTIO/Chiron
57009.749 | 0.40 | 0.08 | CTIO/Chiron
57012.289 | 0.45 | 0.09 | ESO/UVES
57012.290 | 0.45 | 0.09 | ESO/UVES
57012.817 | 0.41 | 0.08 | CTIO/Chiron
57013.811 | 0.41 | 0.08 | CTIO/SMARTS
57014.738 | 0.43 | 0.09 | CTIO/SMARTS
57015.766 | 0.43 | 0.09 | CTIO/SMARTS
57016.796 | 0.44 | 0.09 | CTIO/SMARTS
57018.779 | 0.44 | 0.09 | CTIO/SMARTS
57021.836 | 0.40 | 0.08 | CTIO/SMARTS
57022.752 | 0.46 | 0.09 | CTIO/SMARTS
57025.828 | 0.41 | 0.08 | CTIO/SMARTS
57026.700 | 0.45 | 0.09 | CTIO/Chiron
57027.351 | 0.45 | 0.09 | ESO/UVES
57027.352 | 0.44 | 0.09 | ESO/UVES
57030.691 | 0.41 | 0.08 | CTIO/SMARTS
57032.818 | 0.41 | 0.08 | CTIO/SMARTS
57035.729 | 0.35 | 0.07 | CTIO/SMARTS
57037.816 | 0.31 | 0.06 | CTIO/SMARTS
57038.852 | 0.29 | 0.06 | CTIO/SMARTS
57039.834 | 0.33 | 0.07 | CTIO/Chiron
57040.712 | 0.32 | 0.06 | CTIO/SMARTS
57043.846 | 0.31 | 0.06 | CTIO/SMARTS
57046.685 | 0.29 | 0.06 | CTIO/SMARTS
57047.306 | 0.33 | 0.07 | ESO/UVES
57047.685 | 0.31 | 0.06 | CTIO/SMARTS
57048.810 | 0.29 | 0.06 | CTIO/SMARTS
57050.732 | 0.30 | 0.06 | CTIO/SMARTS
57051.847 | 0.33 | 0.07 | CTIO/Chiron
57059.790 | 0.37 | 0.07 | CTIO/Chiron
57060.663 | 0.37 | 0.07 | CTIO/Chiron
57061.851 | 0.37 | 0.07 | CTIO/Chiron
57062.697 | 0.36 | 0.07 | CTIO/Chiron
57063.735 | 0.37 | 0.07 | CTIO/Chiron
57064.776 | 0.38 | 0.08 | CTIO/SMARTS
57068.771 | 0.33 | 0.07 | CTIO/SMARTS
57070.647 | 0.37 | 0.07 | CTIO/Chiron
57074.800 | 0.34 | 0.07 | CTIO/Chiron
57075.700 | 0.35 | 0.07 | CTIO/Chiron
57078.899 | 0.31 | 0.06 | CTIO/SMARTS
57083.662 | 0.37 | 0.07 | CTIO/SMARTS
57088.642 | 0.33 | 0.07 | CTIO/SMARTS
57091.593 | 0.39 | 0.08 | CTIO/SMARTS
57092.723 | 0.37 | 0.07 | CTIO/SMARTS
57093.711 | 0.37 | 0.07 | CTIO/SMARTS
57095.800 | 0.34 | 0.07 | CTIO/Chiron
57097.696 | 0.32 | 0.06 | CTIO/Chiron
57104.561 | 0.36 | 0.07 | CTIO/Chiron
57115.749 | 0.40 | 0.08 | CTIO/SMARTS
57118.557 | 0.41 | 0.08 | CTIO/SMARTS
57120.539 | 0.40 | 0.08 | CTIO/SMARTS
57124.499 | 0.42 | 0.08 | CTIO/Chiron
57125.524 | 0.39 | 0.08 | CTIO/Chiron
57127.619 | 0.41 | 0.08 | CTIO/Chiron
57130.544 | 0.43 | 0.09 | CTIO/SMARTS
57132.516 | 0.43 | 0.09 | CTIO/SMARTS
57134.626 | 0.43 | 0.09 | CTIO/SMARTS
57145.627 | 0.41 | 0.08 | CTIO/SMARTS
57147.629 | 0.46 | 0.09 | CTIO/SMARTS
57150.617 | 0.44 | 0.09 | CTIO/Chiron
57155.575 | 0.40 | 0.08 | CTIO/SMARTS
57161.553 | 0.46 | 0.09 | CTIO/SMARTS
57164.551 | 0.44 | 0.09 | CTIO/SMARTS
57166.534 | 0.45 | 0.09 | CTIO/SMARTS
57172.521 | 0.51 | 0.10 | CTIO/SMARTS
57174.594 | 0.52 | 0.10 | CTIO/Chiron
57177.490 | 0.48 | 0.10 | CTIO/SMARTS
57181.449 | 0.44 | 0.09 | CTIO/SMARTS
57185.503 | 0.38 | 0.08 | CTIO/SMARTS
57189.503 | 0.39 | 0.08 | CTIO/SMARTS
57191.461 | 0.36 | 0.07 | CTIO/SMARTS
57194.500 | 0.39 | 0.08 | CTIO/Chiron
57195.400 | 0.41 | 0.08 | OPD/Coudé
57212.445 | 0.43 | 0.09 | CTIO/SMARTS
57553.000 | 0.62 | 0.12 | ESO/FEROS
57554.451 | 0.63 | 0.13 | CTIO/Chiron
57732.342 | 0.65 | 0.13 | OPD/Coudé
57887.463 | 0.80 | 0.16 | OPD/Coudé
57912.409 | 0.85 | 0.17 | OPD/Coudé
58097.250 | 0.50 | 0.10 | OPD/Coudé
58200.600 | 0.44 | 0.09 | OPD/Coudé
58474.626 | 0.41 | 0.08 | SASER/PC
58480.996 | 0.43 | 0.09 | SASER/TB
58485.014 | 0.47 | 0.09 | SASER/TB
58502.445 | 0.46 | 0.09 | LCOGT/NRES
58502.452 | 0.38 | 0.08 | LCOGT/NRES
58502.452 | 0.35 | 0.07 | CTIO/Chiron
58515.051 | 0.30 | 0.06 | SASER/PMG
58521.981 | 0.27 | 0.05 | SASER/TB
58529.006 | 0.27 | 0.05 | SASER/KH
58534.458 | 0.27 | 0.05 | OPD/Coudé
58534.740 | 0.25 | 0.05 | OPD/Coudé
58541.014 | 0.26 | 0.05 | OPD/Coudé
58545.898 | 0.25 | 0.05 | SASER/TB
58550.458 | 0.23 | 0.05 | OPD/Coudé
58554.925 | 0.33 | 0.07 | SASER/TB
58556.508 | 0.37 | 0.07 | OPD/Coudé
58557.422 | 0.39 | 0.08 | SASER/KH
58557.920 | 0.38 | 0.08 | SASER/KH
58558.422 | 0.39 | 0.08 | SASER/KH
58558.958 | 0.38 | 0.08 | SASER/KH
58559.938 | 0.40 | 0.08 | SASER/DBH