J/A+A/682/A12 ESMORGA, Gaia astrometric binaries masses (Perez-Couto+, 2024)
Methodology for obtaining the relative orbit and individual masses of Gaia
astrometric binaries.
Perez-Couto X., Docobo J.A., Campo P.P
<Astron. Astrophys. 682, A12 (2024)>
=2024A&A...682A..12P 2024A&A...682A..12P (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Binaries, orbits ; Stars, masses ;
Photometry ; Optical ; Parallaxes, trigonometric ;
Proper motions ; Effective temperatures
Keywords: methods: data analysis - methods: numerical - astrometry -
binaries: general
Abstract:
The recent Gaia Data Release 3 has revealed a catalogue of more than
eight hundred thousand binary systems. The release provides orbital
solutions for half of the systems, with the majority of them being
unresolved astrometric binaries. However, some astrophysical
parameters that can only be derived from the relative orbit and
spectroscopic data, such as the spectral type and the mass of each
companion, remain unknown in most of them.
The purpose of this work is to develop a methodology that allows to
obtain those fundamental stellar parameters, and those related to the
geometry and thus ephemeris of the system, in order to know if it can
be optically resolved.
To obtain precise values for each component, we propose an analytic
algorithm to estimate the only two possible relative orbits and pairs
of masses of main-sequence astrometric binaries using all the
available astrometric, photometric and spectroscopic data in the Gaia
DR3. In some cases, it is possible to select the solution that is more
aligned with the rest of the data.
We deduce not only the two possible values of the individual spectral
types, masses and effective temperatures for each binary but also the
size of the telescope necessary to resolve their components. The
workflow of our algorithm as well as the ESMORGA (Ephemeris, Stellar
Masses, and relative ORbits from GAia) catalogue with individual
masses, spectral types, and effective temperatures for 49530 binaries
derived from its application is also presented.
Description:
Here we present the Campbell orbital elements, minimum and maximum
angular separations, individual masses, absolute magnitudes, and
effective temperatures for 49530 Gaia astrometric binaries. The
parameters were obtained by applying the algorithm described in the
paper above to main-sequence Gaia astrometric binaries. The algorithm
provides up to two possible solutions for each binary. If two
solutions are provided, they appear in consecutive rows.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 303 88417 *Catalog of orbital parameters for 49530 binaries
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Note on catalog.dat: Each line corresponds to a solution for the binary.
If two solutions are provided, they appear in consecutive rows.
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 identifier
21- 50 A30 --- NNSmodel Solution type (solution_type)
52- 60 F9.5 deg RAdeg Right ascension (ICRS) at Ep=2016.0
62- 70 F9.5 deg DEdeg Declination (ICRS) at Ep=2016.0
72- 79 F8.5 mas Plx Parallax
81- 85 F5.2 mag Gmag Apparent magnitude (G-band)
87- 91 F5.2 mag GMAG Absolute magnitude (G-band)
93- 96 F4.2 mag dm Magnitude difference (G-band)
98-102 F5.2 mag GMAGA Absolute magnitude of the primary (G-band)
104-108 F5.2 mag GMAGB Absolute magnitude of the secondary (G-band)
110-114 F5.2 Msun MassA Mass of the primary
117-120 F4.2 Msun MassB Mass of the secondary
123-127 I5 K TeffA Effective temperature of the primary
129-133 I5 K TeffB Effective temperature of the secondary
135-142 F8.5 yr P Period
144-153 F10.5 yr T Time of periastron
155-160 F6.4 --- e Eccentricity
162-167 F6.4 arcsec a Semi-major axis of the relative orbit
169-174 F6.2 deg I Inclination
176-181 F6.2 deg Omega Angle of the node
183-188 F6.2 deg omega Argument of the periastron
190-195 F6.4 arcsec rhoMax Maximum angular separation
197-203 F7.2 yr dateMax Date of the maximum angular separation
205-210 F6.4 arcsec rhoMin Minimum angular separation
212-218 F7.2 yr dateMin Date of the minimum angular separation
220-221 A2 --- Grade Grade (1)
223-229 F7.5 mas e_Plx Parallax error
231-234 F4.2 Msun e_MassA Mass of the primary error
236-239 F4.2 Msun e_MassB Mass of the secondary error
241-247 F7.5 yr e_P Period error
249-255 F7.5 yr e_T Time of periastron error
257-262 F6.4 --- e_e Eccentricity error
264-269 F6.4 arcsec e_a Semi-major axis of the relative orbit error
271-275 F5.2 deg e_I Inclination error
277-282 F6.2 deg e_Omega Angle of the node error
284-289 F6.2 deg e_omega Argument of the periastron error
291-296 F6.4 arcsec e_rhoMax Maximum angular separation error
298-303 F6.4 arcsec e_rhoMin Minimum angular separation error
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Note (1): The column "Grade" makes reference to the degree of consonance
between the primary mass in ESMORGA with that of gaiadr3.binarymasses
(Gaia Collaboration et al., 2023) in the case of an astrometric orbit of
between primary and secondary ESMORGA and Gaia masses in the case of an
astrospectroscopic orbit.
Grade ranges from 5 (bad) to 1 (very consonant) and an asterisk (*) is added
next to the grade number if the binary mass functions are similar in both
catalogues in the case of astrospectroscopic solutions.
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Acknowledgements:
Xavier Perez-Couto, xabier.perez.couto(at)usc.es
(End) Patricia Vannier [CDS] 23-Nov-2023