J/ApJS/235/5 EA-type eclipsing binaries observed by LAMOST (Qian+, 2018)
Physical properties and evolutionary states of EA-type eclipsing binaries
observed by LAMOST.
Qian S.-B., Zhang J., He J.-J., Zhu L.-Y., Zhao E.-G., Shi X.-D., Zhou X.,
Han Z.-T.
<Astrophys. J. Suppl. Ser., 235, 5 (2018)>
=2018ApJS..235....5Q 2018ApJS..235....5Q
ADC_Keywords: Binaries, eclipsing; Effective temperatures; Spectral types;
Abundances, [Fe/H]; Radial velocities
Keywords: binaries: close ; binaries: eclipsing ; binaries: spectroscopic ;
stars: evolution ; stars: fundamental parameters
Abstract:
About 3196 EA-type binaries (EAs) were observed by LAMOST by 2017 June
16 and their spectral types were derived. Meanwhile, the stellar
atmospheric parameters of 2020 EAs were determined. In this paper,
those EAs are cataloged and their physical properties and evolutionary
states are investigated. The period distribution of EAs suggests that
the period limit of tidal locking for the close binaries is about 6
days. It is found that the metallicity of EAs is higher than that of
EW-type binaries (EWs), indicating that EAs are generally younger than
EWs and they are the progenitors of EWs. The metallicities of
long-period EWs (0.4<P<1 days) are the same as those of EAs with the
same periods, while their values of Log (g) are usually smaller than
those of EAs. These support the evolutionary process that EAs evolve
into long-period EWs through the combination of angular momentum loss
(AML) via magnetic braking and case A mass transfer. For short-period
EWs, their metallicities are lower than those of EAs, while their
gravitational accelerations are higher. These reveal that they may be
formed from cool short-period EAs through AML via magnetic braking
with little mass transfer. For some EWs with high metallicities, they
may be contaminated by material from the evolution of unseen neutron
stars and black holes or they have third bodies that may help them to
form rapidly through a short timescale of pre-contact evolution. The
present investigation suggests that the modern EW populations may have
formed through a combination of these mechanisms.
Description:
About 3196 EA-type binaries (EAs) shown in the VSX catalog were
observed by LAMOST in the time interval between 2011 October 24 and
2017 June 16.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 84 62 Mean atmospheric parameters and their standard
errors for 62 EAs observed 4 times or more
table2.dat 170 2956 The catalog of the stellar atmospheric parameters
for EAs observed by LAMOST
table3.dat 105 1748 Spectral types of EAs determined by LAMOST
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
J/MNRAS/357/497 : Kinematics of W UMa-type binaries (Bilir+, 2005)
J/MNRAS/373/1483 : W UMa type and CAB stars dynamical evolution (Eker+, 2006)
J/AJ/131/2986 : Multiplicity of contact binaries (Pribulla+, 2006)
J/AJ/132/769 : Radial velocities of 10 close binaries (Pribulla+, 2006)
J/AJ/133/1977 : Radial velocities of 10 close binaries (Pribulla+, 2007)
J/AJ/136/586 : Radial velocities of 10 close binaries (Rucinski+, 2008)
J/ApJ/696/870 : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)
J/AJ/137/3646 : Radial velocities of 10 close binaries (Pribulla+, 2009)
J/MNRAS/405/1930 : Period changes of EA-, EB- & EW-types bin. (Liao+, 2010)
J/other/RAA/11.924 : Atmospheric parameters for 771 stars (Wu+, 2011)
J/A+A/525/A71 : Atmospheric parameters for 1273 stars (Wu+, 2011)
J/AJ/146/101 : LINEAR. III. Periodic variables (Palaversa+, 2013)
J/AJ/145/39 : Differential BV(RI)c light curves of PY Vir (Zhu+, 2013)
J/ApJS/213/9 : Catalina Surveys periodic variable stars (Drake+, 2014)
J/MNRAS/437/185 : W UMa-type contact binaries ages and masses (Yildiz, 2014)
J/AJ/149/120 : Times of minimum light for TY UMa (Li+, 2015)
J/A+A/594/A39 : LAMOST-Kepler param. & activity indicators (Frasca+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1-30 A30 --- Name Variable star identifier
32-42 F11.6 d Per [0.3/98]? Orbital period
44-44 I1 --- Nobs [4/7] Number of observations
46-52 F7.2 K Teff [4272/7448] Averaged effective temperature
54-59 F6.2 K e_Teff [9/251] Error in Teff
61-65 F5.3 [cm/s2] logg [2.6/4.7] Averaged log of gravitational
acceleration
67-71 F5.3 [cm/s2] e_logg [0.01/0.3] Error in logg
73-78 F6.3 [Sun] [Fe/H] [-0.71/0.4] Metallicity
80-84 F5.3 [Sun] e_[Fe/H] [0.008/0.2] Error in [Fe/H]
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 30 A30 --- Name Variable star identifier
32- 40 F9.5 deg RAdeg VSX right ascension in decimal degrees (J2000)
42- 50 F9.5 deg DEdeg VSX declination in decimal degrees (J2000)
52- 63 A12 --- Type Variability type, as in GCVS catalog
65- 78 F14.9 d Per [0.2/1324.3]? Period of the variable
from the VSX catalog
80 A1 --- f_Per [:N] Flag on Per (G1)
82- 86 F5.3 arcsec Sep [0/2] Distance between VSX and LAMOST
coordinates
88- 97 A10 "Y/M/D" Date Observed date
99-103 A5 --- SpT MK spectral type
105-111 F7.2 K Teff [3880/8490] Effective temperature
113-120 F8.2 K e_Teff [1.4/790]?=-9999 Error in Teff
122-126 F5.3 [cm/s2] logg [1.7/5] Logarithm of acceleration of gravity
128-136 F9.3 [cm/s2] e_logg [0/1.2]?=-9999 Error in logg
138-143 F6.3 [Sun] [Fe/H] [-1.7/0.7] Metallicity
145-153 F9.3 [Sun] e_[Fe/H] [0/0.8]?=-9999 Error in [Fe/H]
155-161 F7.2 km/s RV [-214/176] Radial velocity
163-170 F8.2 km/s e_RV [0.3/91]?=-9999 Error in RV
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 30 A30 --- Name Variable star identifier
32- 40 F9.5 deg RAdeg VSX right ascension in decimal degrees (J2000)
42- 50 F9.5 deg DEdeg VSX declination in decimal degrees (J2000)
52- 63 A12 --- Type Variability type, as in GCVS catalog
65- 80 F16.10 d Per [0.1/25245]? Period of the variable from
the VSX catalog
81- 82 A2 --- f_Per Flag on Per (G1)
84- 88 F5.3 arcsec Sep [0/2] Distance between VSX and LAMOST coordinates
90- 99 A10 "Y/M/D" Date Observed date
101-105 A5 --- SpT MK spectral type
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Global notes:
Note (G1):
: = uncertain value;
N = the real period is likely a multiple of the quoted period.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 17-Aug-2018