J/A+A/692/A247 Gaia orbital and accelerated sources (Bashi+, 2024)
Searching for compact hierarchical triple systems candidates in astrometric
binaries and accelerated solutions.
Bashi D., Tokovinin A.
<Astron. Astrophys. 692, A247 (2024)>
=2024A&A...692A.247B 2024A&A...692A.247B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, distances ;
Radial velocities ; Stars, masses ; Stars, fundamental
Keywords: methods: data analysis - methods: statistical - astrometry -
binaries: general - stars: statistics
Abstract:
Compact hierarchical triple (CHT) systems, where a tertiary component
orbits an inner binary, provide critical insights into stellar
formation and evolution. Despite their importance, the detection of
such systems, especially compact ones, remains challenging due to the
complexity of their orbital dynamics and the limitations of
traditional observational methods.
This study aims to identify new CHT star systems among Gaia astrometric
binaries and accelerated solutions by analysing the radial velocity (RV)
amplitude of these systems, thereby improving our understanding of stellar
hierarchies.
We selected a sample of bright astrometric binaries and accelerated
solutions from the Gaia DR3 Non-Single Star catalogue. The RV
peak-to-peak amplitude was used as an estimator, and we applied a new
method to detect potential triple systems by comparing the RV-based
semi-amplitude with the astrometric semi-amplitude. We used available
binary and triple star catalogues to identify and validate candidates,
with a subset confirmed through further examination of the RV and
astrometric data.
Our analysis involved compiling lists of Gaia orbital and accelerated
sources, sorted by the difference between RV-based and astrometric
semi-amplitudes ({DELTA}K) and by radial velocity standard deviation
(σRV), respectively. These lists (Tables 1 and 4) include all
sources analysed, not only the identified CHT candidates. From these
data, we identified 956 CHT candidates among the orbital sources and
another 3115 probable close binary sources among the accelerated
solutions.
Description:
The data tables contain information on Gaia orbital and accelerated
sources from the Gaia DR3 Non-Single Star catalogue, sorted by the
difference between RV-based and astrometric semi-amplitudes
({DELTA}K) and by radial velocity standard deviation (σRV),
respectively.
Table 1 lists Gaia orbital source IDs sorted by {DELTA}K, including
all sources analysed, not only the CHT candidates. The exact cut used
to identify the 956 CHT candidates is {DELTA}K>5km/s.
Table 4 lists Gaia accelerated source IDs sorted by σRV,
including all sources analysed, not only the close binaries in
accelerated solutions. The exact cut used to identify the 3115 triple
candidates is based on the relation:
log10(RVsig)>0.22356214723314+exp(0.703222411*(grvsmag-12.73160))
+3*10^(0.262670 - 0.0873498006*grvs_mag)
where RV_sig is the radial velocity standard deviation, and grvs_mag
is the integrated GRVS magnitude from Gaia.
For each source, we provide the Gaia DR3 source identifier, right
ascension and declination, various semi-amplitudes derived from
astrometric and radial velocity data, and other relevant parameters.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 104 19858 Gaia orbital sources sorted by {DELTA}K
table4.dat 101 81852 Gaia accelerated sources sorted by σRV
--------------------------------------------------------------------------------
See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source identifier
21- 35 F15.11 deg RAdeg Right Ascension (ICRS) at epoch 2016.0
37- 51 F15.11 deg DEdeg Declination (ICRS) at epoch 2016.0
53- 61 F9.6 km/s K0 Astrometric semi-amplitude
63- 72 F10.6 km/s K1 RV-based semi-amplitude
74- 83 F10.6 km/s e_K0 Error in K0
85- 93 F9.6 km/s e_K1 Error in K1
95-104 F10.6 km/s Kdiff Difference between K0 and K1 in sigmas
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source identifier
21- 35 F15.11 deg RAdeg Right Ascension (ICRS) at epoch 2016.0
37- 51 F15.11 deg DEdeg Declination (ICRS) at epoch 2016.0
53- 60 F8.6 AU/yr2 acc Astrometric acceleration,
derived from Gaia DR3 data
62- 71 F10.6 km/s sK1 Estimated semi-amplitude sK1
73- 81 F9.6 km/s e_sK1 Error in sK1
83- 92 F10.6 km/s RVsig Radial velocity standard deviation
from Gaia DR3 (RV_sig)
94-101 F8.5 mag GmagRVS Gaia integrated GRVS magnitude
--------------------------------------------------------------------------------
Acknowledgements:
Dolev Bashi, db975(at)cam.ac.uk [Cambridge]
Andrei Tokovinin, andrei.tokovinin(at)noirlab.edu [NOIRLab]
We acknowledge the use of data from the European Space Agency (ESA)
mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia
Data Processing and Analysis Consortium (DPAC,
https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the
DPAC has been provided by national institutions, in particular the
institutions participating in the Gaia Multilateral Agreement.
(End) D. Bashi [Cambridge], A. Tokovinin [NOIRLab], P. Vannier [CDS] 25-Nov-2024