J/ApJS/257/22 Early-type star stellar rotations in LAMOST MRS. I. (Sun+, 2021)
Exploring the stellar rotation of early-type stars in the LAMOST
medium-resolution survey.
I. Catalog.
Sun W., Duan X.-W., Deng L., de Grijs R., Zhang Bo, Liu C.
<Astrophys. J. Suppl. Ser., 257, 22 (2021)>
=2021ApJS..257...22S 2021ApJS..257...22S
ADC_Keywords: Stars, early-type; Rotational velocities; Effective temperatures;
Spectra, optical; Radial velocities; Abundances; Stars, masses;
Surveys
Keywords: Stellar rotation ; Astronomy data analysis ; Catalogs ;
Early-type stars ; Stellar properties
Abstract:
We derive stellar parameters and abundances ("stellar labels") of
40034 late-B and A-type main-sequence stars extracted from the Large
Sky Area Multi-Object Fiber Spectroscopic Telescope Medium Resolution
Survey (LAMOST-MRS). The primary selection of our early-type sample
was obtained from LAMOST Data Release 7 based on spectral-line
indices. We employed the Stellar Label Machine to derive their
spectroscopic stellar parameters, drawing on Kurucz spectral synthesis
models with 6000<Teff<15000K and -1<[M/H]<1dex. For a signal-to-noise
ratio of ∼60, the cross validated scatter is ∼75K, 0.06dex, 0.05dex,
and ∼3.5km/s for Teff, logg, [M/H], and vsini, respectively. A
comparison with objects with prior known stellar labels shows great
consistency for all stellar parameters, except for logg. Although this
is an intrinsic caveat that comes from the MRS's narrow wavelength
coverage, it only has a minor effect on estimates of the stellar
rotation rates because of the decent spectral resolution and the
profile-fitting method employed. The masses and ages of our early-type
sample stars were inferred from nonrotating stellar evolution models.
This paves the way for reviewing the properties of stellar rotation
distributions as a function of stellar mass and age.
Description:
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)
is a 4m quasi-meridian reflective Schmidt telescope equipped with
4000 fibers across its 5° field-of-view focal plane. Following the
initial low-spectral-resolution (R∼1800) survey (LRS), conducted from
2011 to 2018, LAMOST has been conducting a medium-resolution survey (MRS),
R∼7500, with its upgraded spectrographs (LAMOST-II;
Liu+ 2020, arXiv:2005.07210). The blue cameras of each spectrograph
cover the wavelength range from 4950 to 5350Å, while the red
cameras cover 6300 to 6800Å.
MRS DR7 contains 11,422,346 single-exposure and 2,968,667 coadded
spectra (encompassing both the blue and red bands), which are
tabulated in the LAMOST MRS General Catalog.
Here, we construct a data-driven model for medium-resolution spectra
based on the Stellar LAbel Machine (SLAM; Zhang+ 2020, J/ApJS/246/9)
model trained by ATLAS12 atmospheric models (Kurucz 2005MSAIS...8..189K 2005MSAIS...8..189K).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 187 40034 Catalog of stellar parameters from LAMOST DR7
medium-resolution survey (MRS) spectra and
Gaia EDR3
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See also:
B/pastel : The PASTEL catalogue (Soubiran+, 2016-)
B/pollux : POLLUX database of synthetic stellar spectra (Palacios+ 2010-2021)
III/226 : Rotational Velocities of Stars (Glebocki+ 2000)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/ApJS/94/687 : Old stellar populations. V. (Worthey+, 1994)
J/A+A/381/105 : Rotational velocities of A-type stars. I. (Royer+, 2002)
J/A+A/393/897 : Rotational velocities of A-type stars II. (Royer+, 2002)
J/ApJ/648/591 : Stellar rotation in young clusters. II. (Huang+, 2006)
J/ApJ/648/580 : Rotational velocities in 19 open clusters (Huang+, 2006)
J/ApJ/718/683 : The edge of the young Galactic disk (Carraro+, 2010)
J/ApJ/722/605 : A stellar rotation census of B stars (Huang+, 2010)
J/A+A/530/A115 : Rotating massive MS stars evolutionary models (Brott+, 2011)
J/A+A/531/A143 : Rotational velocities of HR stars (Diaz+, 2011)
J/A+A/537/A146 : Stellar models with rot. 0.8<M<120, Z=0.014 (Ekstrom+, 2012)
J/A+A/537/A120 : Rotational velocities of A-type stars. IV. (Zorec+, 2012)
J/MNRAS/449/1401 : Am stars candidates from LAMOST DR1 (Hou+, 2015)
J/ApJ/808/16 : Cannon: a new approach to determine abundances (Ness+, 2015)
J/AJ/153/99 : Galactic outer disk: toward Tombaugh 1 (Carraro+, 2017)
J/A+A/616/L15 : Parallaxes and Proper Motions of OB stars (Xu+, 2018)
J/ApJS/241/32 : OB stars from the LAMOST DR5 spectra (Liu+, 2019)
J/ApJS/245/34 : Abund. for 6 million stars from LAMOST DR5 (Xiang+, 2019)
J/ApJS/246/9 : Stellar parameters of LAMOST stars using SLAM (Zhang+, 2020)
J/ApJ/891/23 : Stellar abundances from LAMOST MRS (SPCAnet) (Wang+, 2020)
J/A+A/649/A3 : Gaia EDR3 photometric passbands (Riello+, 2021)
http://dr7.lamost.org/ : LAMOST DR7 home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaEDR3 Gaia EDR3 source identifier
21- 29 I9 --- obsid [588904135/747816243] LAMOST MRS observation
identifier
31- 45 F15.11 deg RAdeg Gaia EDR3 right ascension (ICRS)
at Ep=2016.0
47- 60 F14.11 deg DEdeg Gaia EDR3 declination (ICRS) at Ep=2016.0
62- 65 F4.2 0.1nm EWHa [2.4/10] Line indice, Hα equivalent
width, Angstroms
67- 71 F5.2 0.1nm EWMg [-0.2/10] Line indice, Mg Ib equivalent
width, Angstroms
73- 79 F7.2 km/s RVelb [-249.2/250] Radial velocity, blue arm
81- 87 F7.2 km/s RVelr [-204/184] Radial velocity, red arm
89- 93 I5 K Teff [7000/14499] Effective temperature from SLAM
95- 97 I3 K e_Teff [0/401] Uncertainty in Teff
99-102 F4.2 [cm/s2] logg [3.13/4.84] Surface gravity from SLAM
104-107 F4.2 [cm/s2] e_logg [0/0.5] Uncertainty in logg
109-113 F5.2 [-] [M/H] [-1.34/0.7] Metallicity from SLAM
115-118 F4.2 [-] e_[M/H] [0/0.3] Uncertainty in [M/H]
120-124 F5.1 km/s vsini [3.5/449.5] Projected rotation velocity
from SLAM
126-129 F4.1 km/s e_vsini [0/18] Uncertainty in vsini
131-135 F5.3 [Lsun] logLstar [0.7/3.4] Logarithmic luminosity
137-141 F5.3 [Lsun] e_logLstar [0.012/0.12] Uncertainty in logLstar
143-146 F4.2 Msun Mstar [1.5/6.1] Stellar mass
148-151 F4.2 Msun e_Mstar [0/0.1] Uncertainty in Mstar
153-156 F4.2 --- t/tms [0/1] Life span from the zero-age main
sequence (ZAMS) to the terminal-age main
sequence (TAMS)
158-161 F4.2 --- e_t/tms [0/0.15] Uncertainty in t/tms
163-167 F5.1 --- SNRb [0/999] Signal-to-noise ratio, blue arm
169-173 F5.1 --- SNRr [0/999] Signal-to-noise ratio, red arm
175-180 F6.3 --- chi2b [0/24] χ^2 estimate of best fit of
blue arm
182-187 F6.3 --- chi2r [0.06/28.5] χ^2 estimate of best fit
of red arm
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Feb-2022