J/A+A/674/A10 Gaia DR3 systems with companions (Holl+, 2023)
Gaia Data Release 3.
Astrometric orbit determination with Markov Chain Monte Carlo and genetic
algorithms. Systems with stellar, substellar, and planetary mass companions.
Holl B., Sozzetti A., Sahlmann J., Giacobbe P., Segransan D., Unger N.,
Delisle J.B., Barbato D., Lattanzi M.G., Morbidelli R., Sosnowska D.
<Astron. Astrophys. 674, A10 (2023)>
=2023A&A...674A..10H 2023A&A...674A..10H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Radial velocities ; Optical
Keywords: astrometry - planets and satellites: detection -
techniques: radial velocities - catalogs -
brown dwarfs - binaries: general
Abstract:
Astrometric discovery of sub-stellar mass companions orbiting stars is
exceedingly hard due to the required sub-milliarcsecond precision,
limiting the application of this technique to only a few instruments
on a target-per-target basis as well as the global astrometry space
missions Hipparcos and Gaia. The third Gaia data release includes the
first Gaia astrometric orbital solutions, whose sensitivity in terms
of estimated companion mass extends down into the planetary-mass
regime. We present the contribution of the 'exoplanet pipeline' to the
Gaia DR3 sample of astrometric orbital solutions by describing the
methods used for fitting the orbits, the identification of significant
solutions, and their validation. We then present an overview of the
statistical properties of the solution parameters. Using both a Markov
Chain Monte Carlo and Genetic Algorithm we fit the 34 months of Gaia
DR3 astrometric time series with a single Keplerian astrometric-orbit
model. Verification and validation steps are taken using significance
tests, internal consistency checks using the Gaia radial velocity
measurements (when available), as well as literature radial velocity
and astrometric data, leading to a subset of candidates that are
labelled as 'validated'. We determined astrometric-orbit solutions for
1162 sources and 198 solutions have been assigned the 'validated'
label. Precise companion mass estimates are presented elsewhere. From
internal and external verification and validation we estimate the
level of spurious/incorrect solutions in our sample to be of the order
of ∼5-10% in our non-'validated' candidate samples. We demonstrate
that Gaia is able to confirm and sometimes refine known orbital
companion orbits as well as identify new candidates, providing us with
a positive outlook of the expected harvest from the full mission data
in future data releases.
Description:
refsols.dat: Overview of all sources we published in Gaia DR3 table
"nsstwobody_orbit" (Cat. I/357) for which we have identified
reference data. Asymmetric uncertainties available for some of the
literature sources have been set to the largest absolute uncertainty.
For all radial velocity time series below, the maximum included
observation date is JD 2459519.5 (1 Nov 2021), which is the time at
which the validations for this paper were done:
bd-18113.dat: CORALIE radial velocity time series first published with
this publication.
46_10046.dat: CORALIE radial velocity time series for CD-46 10046
first published with this publication.
gj812a.dat: HARPS03 radial velocity time series from the HARPS- ESO
public archive program id: 183.C-0437(A) (Bonfils).
gj9732.dat: HARPS03 radial velocity time series from the HARPS- ESO
public archive program id: 180.C-0886(A) and 183.C-0437(A) (Bonfils).
hd26596.dat: radial velocity time series from the SOPHIE public
archive http://atlas.obs-hp.fr/sophie/.
hd40503.dat: HARPS03 program id: 085.C-0019(A) (Lo Curto) and CORALIE
radial velocity time series, first published with this publication.
hd68638.dat: ELODIE radial velocity time series from the ELODIE public
archive http://atlas.obs-hp.fr/elodie/
hd89010.dat: ELODIE - SOPHIE - OHP radial velocity time series from
the SOPHIE and ELODIE public archives.
hd134237.dat: CORALIE (prog. 703) radial velocity time series first
published with this publication.
hd183162.dat: radial velocity time series from HIRES Butler et al.
(2017AJ....153..208B 2017AJ....153..208B), as well as SOPHIE public archive.
hip9095.dat: CORALIE (prog. 714) radial velocity time series series
first published with this publication.
toi-288.dat: ORALIE radial velocity time series from Psardi et al.
(2022A&A...664A..94P 2022A&A...664A..94P).
hd40503.dat: HARPS and CORALIE radial velocity time series data of
HD40503 within the time range BJD [2452989.7078, 2459500.8049].
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sources.dat 49 12 List of sources with radial velocity time series
rv/* . 14 Individual radial velocity time series
refsols.dat 403 204 Reference solution table
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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: sources.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Star Star name
13- 14 I2 h RAh Simbad Right ascension (J2000)
16- 17 I2 min RAm Simbad Right ascension (J2000)
19- 23 F5.2 s RAs Simbad Right ascension (J2000)
25 A1 --- DE- Simbad Declination sign (J2000)
26- 27 I2 deg DEd Simbad Declination (J2000)
29- 30 I2 arcmin DEm Simbad Declination (J2000)
32- 35 F4.1 arcsec DEs Simbad Declination (J2000)
38- 49 A12 --- FileName Name of the file with RV data in
subdirectory rv
--------------------------------------------------------------------------------
Byte-by-byte Description of file: rv/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 F12.4 d BJD Epoch of radial velocity
15- 25 F11.4 m/s RV Radial velocity
27- 34 F8.4 m/s e_RV Radial velocity uncertainty
38- 47 A10 --- Inst Instrument name (HARPS, CORALIE07 or CORALIE14)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refsols.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source_id
22- 51 A30 --- NSSmodel NSS solution type (1)
54- 64 F11.6 d Perl ? Reference period
67- 76 F10.6 d e_Perl ? Uncertainty of reference period
79- 89 F11.6 d Per Our period
92-101 F10.6 d e_Per Uncertainty of our period
104-111 F8.6 --- eccl ? Reference eccentricity
114-121 F8.6 --- e_eccl ? Uncertainty of reference eccentricity
124-131 F8.6 --- ecc Our eccentricity
134-141 F8.6 --- e_ecc Uncertainty of our eccentricity
144 I1 --- pseu-m-idx [0/2] Our companion pseudo mass index (2)
147-169 A23 --- Name Target common name resolvable in Simbad
172-281 A110 --- Ref Reference/description of reference data
284-403 A120 --- n_Ref Additional notes related to reference (data)
--------------------------------------------------------------------------------
Note (1): nsssolutiontype in Gaia DR3 table "nsstwobody_orbit", being one of
"OrbitalAlternativeValidated", "OrbitalTargetedSearch", and
"OrbitalTargetedSearchValidated". Note that we did not identify reference
data for any of our published "OrbitalAlternative" sources.
Note (2): Our derived pseudo mass for the companion, i.e., assuming the primary
has 1M☉, separated in 3 categories used in the paper as a rough way to
separate the mass ranges, as follows:
0 = Mcomp < 20 Mjup
1 = 20 Mjup ≤ Mcomp ≤ 120 Mjup
2 = Mcomp > 120 Mjup
Note that proper mass estimates need additional information, see e.g.:
Gaia Collaboration, Arenou, F., Babusiaux, C., et al. 2022, in prep.
--------------------------------------------------------------------------------
Acknowledgements:
Berry Holl, berry.holl(at)unige.ch
(End) B. Holl/D. Barbato [DoA, Geneva, Switzerland] P. Vannier [CDS] 06-Oct-2022