J/AJ/163/44 Astrometric parameters of 116 unbound stellar pairs (Hansen, 2022)
Unbound Close Stellar Encounters in the Solar Neighborhood.
Hansen B.M.S.
<Astron. J., 163, 44 (2022)>
=2022AJ....163...44H 2022AJ....163...44H
ADC_Keywords: Stars, double and multiple; Positional data; Optical
Keywords: Technosignatures
Abstract:
We present a catalog of unbound stellar pairs, within 100pc of the
Sun, that are undergoing close, hyperbolic, encounters. The data are
drawn from the GAIA EDR3 catalog, and the limiting factors are errors
in the radial distance and unknown velocities along the line of sight.
Such stellar pairs have been suggested to be possible events
associated with the migration of technological civilizations between
stars. As such, this sample may represent a finite set of targets for
a SETI search based on this hypothesis. Our catalog contains a total
of 132 close passage events, featuring stars from across the entire
main sequence, with 16 pairs featuring at least one main-sequence star
of spectral type between K1 and F3. Many of these stars are also in
binaries, so that we isolate eight single stars as the most likely
candidates to search for an ongoing migration event HD87978, HD92577,
HD50669, HD44006, HD80790, LSPMJ2126+5338, LSPMJ0646+1829 and
HD192486. Among host stars of known planets, the stars GJ433 and HR858
are the best candidates.
Description:
In this paper, we therefore seek to identify pairs of stars that meet
the criterion of being in close physical proximity, but which are
gravitationally unbound. To do this, we draw on the results of the
GAIA satellite, which has provided a detailed map of parallaxes and
proper motions for nearby stars. We search for pairs of stars that
have a finite probability of passing within 104 au of one
another-either in the recent past or near future.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 163 116 The sample of close, unbound pairs featuring lower
mass stars
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
III/252 : Pulkovo radial velocities for 35493 HIP stars (Gontcharov, 2006)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
J/A+A/549/A109 : HARPS XXXI. The M-dwarf sample (Bonfils+, 2013)
J/ApJ/767/94 : 1.1-1.9GHz SETI survey of KOIs. I. (Siemion+, 2013)
J/AJ/147/87 : Binaries to multiples. II. Statistical data (Tokovinin, 2014)
J/AJ/152/181 : SETI observations of exoplanets with the ATA (Harp+, 2016)
J/AJ/153/208 : LCES HIRES/Keck radial velocity ExoplanetSurvey (Butler+, 2017)
J/PASP/129/E4501 : Search for extraterrestrial intelligence (Isaacson+, 2017)
J/A+A/616/A37 : Close encounters to the Sun in Gaia DR2 (Bailer-Jones+, 2018)
J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diagrams (Gaia Collaboration, 2018)
J/A+A/623/A72 : Binarity of Hipparcos stars Gaia pm anomaly (Kervella+, 2019)
J/A+A/636/A74 : HARPS radial velocity database (Trifonov+, 2020)
J/ApJS/246/11 : Search for nearby earth analogs. II. RV analysis. (Feng+, 2020)
J/ApJS/247/66 : SUPERWIDE: wide binaries in Gaia & SUPERBLINK (Hartman+, 2020)
J/A+A/649/A6 : Gaia Catalogue of Nearby Stars-GCNS (Gaia collaboration, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 26 A26 --- Name1 Name of first member of encounter pair (1)
28- 33 F6.3 pc Dist1 [13.9/99.6] Distance to first member
35- 40 F6.3 pc E_Dist1 [0.008/89] Upper uncertainty in Dist1
42- 46 F5.3 pc e_Dist1 [0.008/4] Lower uncertainty in Dist1
48 A1 --- l_Gmag1 Limit flag on Gmag1
49- 53 F5.2 mag Gmag1 [6.24/14.9] Apparent Gaia EDR3 G band magnitude
55- 58 F4.2 mag e_Gmag1 [0.01/0.3]? Uncertainty in Gmag1
60- 65 F6.3 --- B-R1 [-0.24/4.15] Gaia EDR3 B-R color
67- 92 A26 --- Name2 Name of second member of encounter pair (1)
94- 99 F6.3 pc Dist2 [13.7/98.9] Distance to second member
101-106 F6.3 pc E_Dist2 [0.002/66] Upper uncertainty in Dist2
108-112 F5.3 pc e_Dist2 [0.002/3] Lower uncertainty in Dist2
114 A1 --- l_Gmag2 Limit flag on Gmag2
115-119 F5.2 mag Gmag2 [6.53/17.5] Apparent Gaia EDR3 G band magnitude
121-124 F4.2 mag e_Gmag2 [0.01/0.2]? Uncertainty in Gmag2
126-129 F4.2 --- B-R2 [0.59/4.47] Gaia EDR3 B-R color
131-135 I5 AU bmin [22/14210] Minimum Impact Parameter
137-142 I6 yr Tmin [-11850/10800] Time of closest approach for bmin
144-147 F4.2 --- Prob [0/0.37] Probability of b within 10000AU
149-153 F5.2 --- Ratio [0.05/13.2] The (1.e4/bmin)2 ratio
155-163 A9 --- Notes Additional information (2)
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Note (1): Object names that begin with J represent the 2MASS designation.
Object names that begin with S represent the SDSS designation.
Object names what begin with W represent the WISEA designation.
Object names that begin with D represent the Gaia DR2 designation.
The object type is given in parentheses after the designation.
Note (2): Spectral types are indicated in the notes with the notation [1/2],
when known, and those members of the encounter pair that are members
of multiple systems are indicated by (bin-i) in the notes section,
where i indicates either the first or second entry in the row.
1 = GD 84 is referenced in papers about low mass companions.
2 = These sources are in a very confused region in DSS/2MASS.
3 = This star is an X-ray source, which may indicate youth.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 08-Apr-2022