J/other/RAA/19.64 LAMOST spectroscopic binaries & variable stars (Qian+, 2019)
More than two hundred and fifty thousand spectroscopic binary or variable star
candidates discovered by LAMOST.
Qian S.-B., Shi X.-D., Zhu L.-Y., Li L.-J., Zhang J., Zhao E.-G.,
Han Z.-T., Zhou X., Fang X.-H., Liao W.-P.
<Res. Astron. Astrophys., 19, 64 (2019)>
=2019RAA....19...64Q 2019RAA....19...64Q (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, spectroscopic ; Stars, variable ; Radial velocities ;
Effective temperatures
Keywords: stars: fundamental parameters - stars: binaries: spectroscopic -
stars: oscillations - stars: binaries: eclipsing -
stars: variables: other
Abstract:
About 786.4 thousand stars were observed by LAMOST twice or more
during the first stage of its spectroscopic survey. The radial
velocity differences for about 256 thousand targets are larger than
10km/s and they are possible spectroscopic binary or variable
candidates (SBVCs). It is shown that most SBVCs are slightly metal
poorer than the Sun. There are two peaks in the temperature
distribution of SBVCs around 5760K and 4870K, while there are three
peaks in the distribution of the gravitational acceleration at 2.461,
4.171 and 4.621cm/s2. The locations of SBVCs on the [Fe/H]-T,
[Fe/H]-logg, logg-T and H-R diagrams are investigated. It is found
that the detected SBVCs could be classified into four groups. The
first group has higher logg∼4.621 and lower T∼4870K which are
mainly cool red dwarf binaries. The second group of SBVCs has logg
around 4.171cm/s2 that includes binaries and pulsating stars such
as δ Sct and γ Dor variables. The gravitational
accelerations of the third group of SBVCs are higher and some of them
are below the zero-age main sequence. They may be contact binaries in
which the primary components are losing energy to the secondaries in
the common envelopes and are at a special stellar evolutionary stage.
The last group is composed of giants or supergiants with logg around
2.461cm/s2 that may be evolved pulsating stars. One target
(C134624.29+333921.2) is confirmed as an eclipsing binary with a
period of 0.65-days. A preliminary analysis suggests that it is a
detached binary with a mass ratio of 0.46. The primary fills its
critical Roche lobe by about 89%, indicating that mass transfer will
occur between the two components.
Description:
The stellar atmospheric parameters of the first 390 SBVCs are shown in
Table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 192 255943 Stellar atmospheric parameters for new binary
and variable star candidates detected by LAMOST
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See also:
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name Variable star identifier,
CHHMMSS.ss_DDMMSS.s
22- 31 A10 "date" Obs.start Observational date of the beginning dateset
32- 33 A2 --- --- [-]
34- 43 A10 "date" Obs.end Observational date of the end dateset
45- 48 A4 --- N Times of observations
54- 60 F7.2 K Teff Effective temperature
67- 72 F6.2 K e_Teff ?=-1 Error of the effective temperature
80- 84 F5.3 [cm/s2] logg Gravitational acceleration logg
91- 96 F6.3 [cm/s2] e_logg ?=-1 Error of the gravitational acceleration
103-108 F6.3 [-] [Fe/H] Metallicity
115-120 F6.3 [-] e_[Fe/H] ?=-1 Error of Metallicity
126-132 F7.2 km/s RVlow Lowest radial velocity
137-144 F8.2 km/s e_RVlow ?=-9999 Error of the lowest radial velocity
150-156 F7.2 km/s RVhigh Highest radial velocity
161-168 F8.2 km/s e_RVhigh ?=-9999 Error of the highest radial velocity
174-180 F7.2 km/s DRV Differences between the lowest and the
highest radial velocities
185-192 F8.2 km/s e_DRV ? Error of the radial velocities difference
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 06-Aug-2019