J/ApJ/942/109 Hot subdwarf stars from LAMOST DR8 (Lei+, 2023)
Hot subdwarf stars identified in LAMOST DR8 with single-lined and composite
spectra.
Lei Z., He R., Nemeth P., Vos J., Zou X., Hu Ke, Xiao H., Yan H., Zhao J.
<Astrophys. J., 942, 109 (2023)>
=2023ApJ...942..109L 2023ApJ...942..109L
ADC_Keywords: Stars, subdwarf; Spectra, optical; Effective temperatures;
Abundances; Parallaxes, trigonometric
Keywords: B subdwarf stars ; Wide binary stars
Abstract:
A total of 222 hot subdwarf stars were identified with LAMOST DR8
spectra, among which 131 stars show composite spectra and have been
decomposed, while 91 stars present single-lined spectra. Atmospheric
parameters of all sample stars were obtained by fitting hydrogen (H)
and helium (He) line profiles with synthetic spectra. Two long-period
composite sdB binaries were newly discovered by combining our sample
with the non-single-star data from Gaia DR3. One of the new systems
presents the highest eccentricity (i.e., 0.5±0.09) among known wide
sdB binaries, which is beyond model predictions. A total of 15 composite
sdB stars fall in the high-probability binary region of the RUWE-AEN
plane and deserve priority follow-up observations to further study
their binary nature. A distinct gap is clearly presented among
temperatures of cool companions for our composite-spectrum sample, but
we could not come to a conclusion as to whether this feature is
connected to the formation history of hot subdwarf stars before their
binary natures are confirmed.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 151 131 131 hot subdwarf stars identified with
composite spectra
table2.dat 105 91 91 hot subdwarf stars identified by
single-lined spectra
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See also:
VI/65 : Evolutionary models of evolved stars (Dorman+ 1993)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/ApJ/419/596 : Pop I UV radiation models (Dorman+, 1993)
J/A+A/400/939 : Stellar parameters of 115 HQS sdB stars (Edelmann+, 2003)
J/A+A/430/223 : Parameters of cool companions of sdB stars (Lisker+, 2005)
J/MNRAS/421/2798 : Radial velocity monitoring of PG 1018-047 (Deca+, 2012)
J/MNRAS/427/2180 : GALEX survey subdwarf atmospheric parameters (Nemeth+, 2012)
J/ApJ/818/202 : Hot subdwarf stars in LAMOST DR1 (Luo+, 2016)
J/A+A/600/A50 : Catalog of hot subdwarf stars (Geier+, 2017)
J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diag. (Gaia Collaboration, 2018)
J/ApJ/868/70 : Hot subdwarf stars from Gaia DR2 and LAMOST DR5 (Lei+, 2018)
J/A+A/621/A38 : Gaia catalogue of hot subluminous stars (Geier+, 2019)
J/MNRAS/486/2169 : White dwarf and subdwarf stars in SDSS DR14 (Kepler+, 2019)
J/ApJ/881/135 : Hot subdwarf stars from Gaia DR2 & LAMOST. II. (Lei+, 2019)
J/ApJ/881/7 : Hot subdwarf stars from LAMOST DR5 & Gaia DR2 (Luo+, 2019)
J/A+A/635/A193 : Catalogue of hot subdwarf stars DR2 (Geier, 2020)
J/ApJ/889/117 : Hot subdwarf stars from Gaia DR2 & LAMOST. I. (Lei+, 2020)
J/A+A/642/A180 : Hot subdwarf stars binarity (Pelisoli+, 2020)
J/ApJS/256/28 : Hot subdwarf stars with Gaia DR2 & LAMOST DR7 (Luo+, 2021)
J/A+A/662/A40 : Hot subdwarf stars studied with Gaia (Culpan+, 2022)
J/A+A/661/A113 : Hot subdwarf stars Rvel variability (Geier+, 2022)
J/ApJS/259/5 : Hot subdwarf candidates from LAMOST DR7 (Tan+, 2022)
http://www.lamost.org/dr8/v1.0/ : LAMOST DR8 homepage
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 F11.7 deg RAdeg LAMOST Right Ascension (J2000)
13- 14 A2 --- Flags Positional flags (G1)
16- 25 F10.7 deg DEdeg [-3/58] LAMOST Declination (J2000)
27- 35 A9 --- OBSID LAMOST observation identifier
37- 39 I3 --- SNRU [10/328] LAMOST u band signal-to-noise
ratio
41- 59 A19 --- Gaia Gaia DR3 identifier
61- 67 F7.4 mas plx [-0.51/4.02]? Gaia DR3 parallax
69- 74 F6.3 --- RUWE [0.7/14.8]? Gaia DR3 RUWE value
76- 81 F6.3 mas AEN [0/16.7] Gaia DR3 astrometric excess
noise value (epsi)
83- 87 F5.2 mag Gmag [10/17.5] Gaia DR3 G band magnitude
89- 93 I5 K Hot-Teff [23550/74200] Hot primary effective
temperature
95- 99 I5 K e_Hot-Teff [20/19720] Uncertainty in Hot-Teff
101- 104 F4.2 [cm/s2] Hot-logg [5/7] Hot primary log surface gravity
106- 109 F4.2 [cm/s2] e_Hot-logg [0.01/1.5] Uncertainty in Hot-logg
111- 115 F5.2 [-] log(He/H) [-7/2.5] Hot primary log He/H number
abundance
117- 120 F4.2 [-] e_log(He/H) [0.01/1.4] Uncertainty in log(He/H)
122- 128 A7 --- Hot-SpC Hot primary spectral class
130- 133 I4 K Cool-Teff [3749/8035] Cool secondary effective
temperature
135- 138 F4.2 [cm/s2] Cool-logg [2/5] Cool secondary log surface gravity
140- 144 F5.2 [Sun] [Fe/H] [-2.5/0.8] Cool secondary metallicity
146- 151 A6 --- Cool-SpC Cool secondary spectral class
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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- 11 F11.7 deg RAdeg LAMOST Right Ascension (J2000)
13- 14 A2 --- Flags Positional flags (G1)
16- 25 F10.7 deg DEdeg [-6.1/76] LAMOST Declination (J2000)
27- 35 A9 --- OBSID LAMOST observation identifier
37- 39 I3 --- SNRU [10/122] LAMOST signal-to-noise ratio
41- 59 A19 --- Gaia Gaia DR3 identifier
61- 65 F5.2 mag Gmag [11.4/18.4] Gaia DR3 G band magnitude
67- 71 I5 K Teff [21500/72360] Effective temperature
73- 76 I4 K e_Teff [30/4720] Uncertainty in Teff
78- 81 F4.2 [cm/s2] logg [5/7.2] log surface gravity
83- 86 F4.2 [cm/s2] e_logg [0.01/0.6] Uncertainty in logg
88- 92 F5.2 [-] log(He/H) [-6.1/3.9] log He/H number abundance
94- 97 F4.2 [-] e_log(He/H) [0.01/0.6] Uncertainty in log(He/H)
99-105 A7 --- SpC Spectral class
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Global notes:
Note (G1): Flag as follows:
* = common star in the Geier 2020A&A...635A.193G 2020A&A...635A.193G catalog
and also have reported atmospheric parameters.
*d = common star in the Geier 2020A&A...635A.193G 2020A&A...635A.193G catalog without
atmospheric parameters.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Nov-2024