J/ApJ/899/62 Stellar parameters from the 1st release of the MaSTar (Chen+, 2020)
Stellar Parameters for the First Release of the MaSTar Library: An Empirical
Approach.
Chen Y.-P., Yan R., Maraston C., Thomas D., Stringfellow G.S., Bizyaev D.,
Gelfand J.D., Beers T.C., Fernandez-Trincado J.G., Lazarz D., Hill L.,
Drory N., Stassun K.G.
<Astrophys. J., 899, 62 (2020)>
=2020ApJ...899...62C 2020ApJ...899...62C
ADC_Keywords: Surveys; Stars, normal; Spectra, optical; Spectra, infrared;
Abundances, [Fe/H]; Effective temperatures;
Keywords: Stellar atmospheres ; Chemical abundances ; Surveys ;
Astronomical reference materials ; Radial velocity ; Spectroscopy ;
Astronomical techniques
Abstract:
We report the stellar atmospheric parameters for 7503 spectra
contained in the first release of the Mapping Nearby Galaxies at
Apache Point Observatory survey (MaNGA) stellar library (MaStar) in
Sloan Digital Sky Survey DR15. The first release of MaStar contains
8646 spectra measured from 3321 unique stars, each covering the
wavelength range 3622-10354Å with a resolving power of R∼1800. In
this work, we first determined the basic stellar parameters: effective
temperature (Teff), surface gravity (logg), and metallicity ([Fe/H]),
which best fit the data using an empirical interpolator based on the
Medium-resolution Isaac Newton Telescope library of empirical spectra
(MILES), as implemented by the University of Lyon Spectroscopic
analysis Software package. While we analyzed all 8646 spectra from the
first release of MaStar, since MaStar has a wider parameter-space
coverage than MILES, not all of these fits are robust. In addition,
not all parameter regions covered by MILES yield robust results,
likely due to the nonuniform coverage of the parameter space by MILES.
We tested the robustness of the method using the MILES spectra itself
and identified a proxy based on the local density of the training set.
With this proxy, we identified 7503 MaStar spectra with robust fitting
results. They cover the range from 3179 to 20517K in effective
temperature (Teff), from 0.40 to 5.0 in surface gravity (logg), and
from -2.49 to +0.73 in metallicity ([Fe/H]).
Description:
The spectra we used in this work are from the first release of MaStar
(Yan+, 2019, J/ApJ/883/175). These spectra span a wavelength
3622-10354Å with a resolving power of R∼1800, and are provided in
DR15 of SDSS-IV (Aguado+, 2019ApJS..240...23A 2019ApJS..240...23A).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 70 7503 MaStar stellar parameters derived in this work
--------------------------------------------------------------------------------
See also:
III/166 : A New Library of Optical Spectra (Silva + 1992)
III/218 : ELODIE archive (Prugniel+, 2001)
III/232 : STELIB: A library of stellar spectra at R∼2000 (Le Borgne+, 2003)
VI/39 : Model Atmospheres (Kurucz, 1979)
VII/102 : Spectrophotometric Atlas of Standard Stellar Spectra (Pickles, 1985)
VI/120 : High-resolution synthetic stellar library (Coelho+, 2005)
J/ApJS/94/687 : Old stellar populations. V. (Worthey+, 1994)
J/A+AS/130/65 : A standard stellar library. II. (Lejeune+ 1998)
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150 - 25000 A (Pickles,1998)
J/A+AS/146/217 : Library of Spectra (0.5 to 2.5um) of Cool Stars (Lancon+,2000)
J/MNRAS/326/959 : Empirical calibration of near-IR Ca triplet (Cenarro+, 2001)
J/ApJS/152/251 : Indo-US library of coude feed stellar spectra (Valdes+, 2004)
J/A+A/417/1055 : Extensive library of synthetic spectra (Zwitter+, 2004)
J/A+A/442/1127 : Library of 2500-10500Å synthetic spectra (Munari+, 2005)
J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)
J/MNRAS/374/664 : Stellar atmospheric param. in MILES library (Cenarro+, 2007)
J/MNRAS/389/585 : Fundamental parameters of M dwarfs (Casagrande+, 2008)
J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009)
J/MNRAS/404/1639 : MILES base models & new line index system (Vazdekis+, 2010)
J/A+A/531/A165 : MILES atmospheric parameters (Prugniel+, 2011)
J/A+A/525/A71 : Atmospheric parameters for 1273 stars (Wu+, 2011)
J/A+A/551/A36 : Metallicity of M dwarfs. III. (Neves+, 2013)
J/A+A/565/A117 : X-Shooter Spectral Library (XSL). DR1 (Chen+, 2014)
J/AJ/151/144 : ASPCAP weights for 15 APOGEE chemical elements (Garcia+, 2016)
J/A+A/585/A64 : New atmospheric parameters of MILES cool stars (Sharma+, 2016)
J/AJ/156/126 : Stellar param. & abund. from BACCHUS analysis (Jonsson+, 2018)
J/ApJ/883/175 : 1st release of the MaNGA Stellar Library (MaStar) (Yan+, 2019)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name MaNGA identifier
13- 21 F9.5 deg RAdeg [0.76/356] Right Ascension (J2000)
23- 32 F10.6 deg DEdeg [-31/86.5] Declination (J2000)
34- 38 I5 K Teff [3179/20517] Effective temperature
40- 43 F4.2 [cm/s2] logg [0.41/5] log, surface gravity
45- 49 F5.2 [-] [Fe/H] [-2.5/0.73] Metallicity
51- 53 I3 K e_Teff [0/118] Uncertainty in Teff
55- 58 F4.2 [cm/s2] e_logg [0/0.14] Uncertainty in logg
60- 63 F4.2 [-] e_[Fe/H] [0/0.09] Uncertainty in [Fe/H]
65- 70 F6.2 --- chi [0.55/130.46] Reduced χ2 of fit
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 15-Oct-2021