J/A+A/706/A249 Sample of Hertzsprung gap sources (Garcia-Moreno+, 2026)
Analysis of mass-transferring binary candidates in the Milky Way.
Garcia-Moreno G., Blagorodnova N., Anders F., Weiler M., Wichern H.,
Britavskiy N., de Wet S.
<Astron. Astrophys. 706, A249 (2026)>
=2026A&A...706A.249G 2026A&A...706A.249G (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Binaries, eclipsing ; Photometry ; Optical
Keywords: binaries: close - binaries: eclipsing - stars: emission-line, Be -
Hertzsprung-Russell and C-M diagrams
Abstract:
Mass transfer between stars in binary systems profoundly impacts their
evolution, yet many aspects of this process (especially the stability,
mass loss, and eventual fate of such systems) remain poorly
understood. One promising avenue to constrain these processes is
through the identification and characterisation of systems undergoing
active mass transfer. Inspired by the slow brightening preceding
stellar merger transients, we worked on a method to identify Galactic
mass-transferring binaries in which the donor is a Hertzsprung gap
star. We constructed an initial sample of Hertzsprung gap stars using
the Gaia EDR3 contribution Starhorse catalogue, and we identified
candidate mass-transferring systems by selecting sources that exhibit
Balmer emission features (as seen in the low-resolution Gaia XP
spectra), mid-infrared excess (from WISE photometry), and photometric
variability (inferred from the error in the Gaia G-band magnitude).
This multi-criteria selection yielded a sample of 67 candidates, which
we further analysed using complementary photometric and spectroscopic
data, as well as information from cross-matched archival catalogues.
Among our candidates, we identified at least nine eclipsing binaries
and some sources that are potential binaries as well. Three sources in
our sample are strong candidates for mass-transferring binaries with a
yellow component, and three more are binaries with a Be star. Notably,
three sources in our sample are strong candidates for hosting a
compact companion, based on their ultraviolet or X-ray signatures. The
main sources of contamination in our search are hot but highly
reddened stars (primarily Oe and Be stars) as well as regular
pulsating stars such as delta Scuti and Cepheid variables. As an
additional outcome of this work, we present a refined new catalogue of
308 Hertzsprung gap stars, selected using improved extinction
corrections and stricter emission-line criteria. This enhanced sample
is expected to contain a significantly higher fraction of
scientifically valuable mass-transferring binaries.
Description:
In this study, we try to find mass-transferring binaries in the
Hertzsprung gap using the Gaia DR3 (Gaia Collaboration et al.,
2016A&A...595A...1G 2016A&A...595A...1G, Cat. I/337, 2023A&A...674A...1G 2023A&A...674A...1G, Cat. I/355)
catalogue and the Gaia EDR3 collaboration catalogue Starhorse (Anders
et al., 2022A&A...658A..91A 2022A&A...658A..91A, Cat. I/354). During the course of this
work, a new catalogue with improved extinction estimates SHBoost
(Khalatyan et al., 2024A&A...691A..98K 2024A&A...691A..98K, Cat. V/160), became available.
We therefore repeated our selection of Hertzsprung gap stars using
SHBoost parameters. This revised selection resulted in a final sample
of 308 Gaia sources, which are provided in this table. The quantities
listed here are taken directly from Gaia DR3 and from the SHBoost
catalogue.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hg_cat.dat 215 308 Our new sample of Hertzsprung gap sources, with
information from the Gaia DR3 and from the
SHBoost catalogues
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/354 : StarHorse2, Gaia EDR3 photo-astrometric distances (Anders+, 2022)
V/160 : SHBoost 2024 (Khalatyan+, 2024)
https://gea.esac.esa.int/archive/ : Gaia archive
https://gaia.aip.de : Gaia@AIP
Byte-by-byte Description of file: hg_cat.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 unique source identifier
(source_id)
21- 40 F20.16 deg RAdeg Right ascension (ICRS) (ra) (1)
42- 61 F20.16 deg DEdeg Declination (ICRS) (dec) (1)
63- 72 F10.7 mag Gmag G-band mean magnitude
(photgmean_mag) (1)
74- 83 F10.8 mag BP-RP BP-RP colour (bp_rp) (1)
85- 95 F11.8 kpc Dist Distance estimate from the literature
(dist) (2)
97-106 F10.8 kpc b_Dist ?=- 16th distance percentile from the
literature (dist_lower) (2)
108-117 F10.8 kpc B_Dist ?=- 84th distance percentile from the
literature (dist_upper) (2)
119-128 F10.8 mag AVmean Line-of-sight extinction at
lambda=5420Å, AV, xgboost-distribution
mean value (xgbdistavmean) (2)
130-139 F10.8 mag s_AVmean Line-of-sight extinction at
lambda=5420Å, AV, xgboost-distribution
standard deviation (xgbdistavstd) (2)
141-149 F9.7 [K] logTeffmean Effective temperature,
xgboost-distribution mean value
(xgbdistlogteffmean) (2)
151-161 F11.9 [K] s_logTeffmean Effective temperature,
xgboost-distribution standard deviation
(xgbdistlogteffstd) (2)
163-172 F10.8 [cm/s2] loggmean Surface gravity, xgboost-distribution mean
value (xgbdistloggmean) (2)
174-183 F10.8 [cm/s2] s_loggmean Surface gravity, xgboost-distribution
standard deviation (xgbdistloggstd) (2)
185-194 F10.7 Msun Massmean Stellar mass, xgboost-distribution mean
value (xgbdistmassmean) (2)
196-215 F20.8 Msun s_Massmean Stellar mass, xgboost-distribution
standard deviation (xgbdistmassstd) (2)
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Note (1): From the Gaia DR3 catalogue (Gaia Collaboration et al. 2016,
Cat. I/337, 2023, Cat. I/355).
Note (2): From the SHBoost catalogue (Khalatyan et al., 2024, Cat. V/160).
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Acknowledgements:
Gerard Garcia-Moreno, ggarcimo(at)fqa.ub.edu
(End) Patricia Vannier [CDS] 01-Dec-2025