J/ApJ/891/23 Stellar abundances from LAMOST MRS (SPCAnet) (Wang+, 2020)
SPCANet: Stellar Parameters and Chemical Abundances Network for LAMOST-II
Medium Resolution Survey.
Wang R., Luo A.-L., Chen J.-J., Hou W., Zhang S., Zhao Y.-H., Li X.-R.,
Hou Y.-H.
<Astrophys. J., 891, 23 (2020)>
=2020ApJ...891...23W 2020ApJ...891...23W
ADC_Keywords: Abundances; Effective temperatures; Radial velocities;
Spectra, optical; Surveys
Keywords: Stellar atmospheres ; Astronomical methods ; Spectroscopy
Abstract:
The fundamental stellar atmospheric parameters (Teff and logg) and
13 chemical abundances are derived for medium-resolution spectroscopy
from Large Sky Area Multi-Object Fiber Spectroscopic Telescope
(LAMOST) Medium Resolution Survey (MRS) data sets with a deep-learning
method. The neural networks we designed, named SPCANet, precisely map
LAMOST MRS spectra to stellar parameters and chemical abundances. The
stellar labels derived by SPCANet have precisions of 119K for Teff and
0.17dex for logg. The abundance precision of 11 elements including
[C/H], [N/H], [O/H], [Mg/H], [Al/H], [Si/H], [S/H], [Ca/H], [Ti/H],
[Cr/H], [Fe/H], and [Ni/H] are 0.06 ∼ 0.12 dex, while that of
[Cu/H] is 0.19dex. These precisions can be reached even for spectra
with signal-to-noise ratios as low as 10. The results of SPCANet are
consistent with those from other surveys such as APOGEE, GALAH, and
RAVE, and are also validated with the previous literature values
including clusters and field stars.
Description:
The medium-resolution survey with the LAMOST spectrograph in
medium-resolution mode of R∼7500, LAMOST-II MRS, began on
2017 September 1. The wavelength coverage of each MRS spectrum
consists of two parts: the blue part (4950-5350Å) and the red part
(6300-6800Å). LAMOST DR7 internally released 5,635,640
medium-resolution spectra, 2,426,237 of which have signal-to-noise
ratios (S/Ns) higher than 10 for both the blue and red part.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 398 1472211 LAMOST MRS Stellar Parameters and Chemical
Abundances catalog
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See also:
III/279 : RAVE 5th data release (Kunder+, 2017)
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009)
J/AJ/142/193 : RAVE stellar elemental abundances (DR1) (Boeche+, 2011)
J/other/RAA/11.924 : Atmospheric parameters for 771 stars (Wu+, 2011)
J/A+A/562/A71 : Abundances of solar neighbourhood dwarfs (Bensby+, 2014)
J/ApJ/808/16 : Cannon: a new approach to determine abundances (Ness+, 2015)
J/A+A/573/A55 : Gaia-ESO Survey: Tr20, NGC 4815 & 6705 (Tautvaisiene+, 2015)
J/AJ/151/144 : ASPCAP weights for 15 APOGEE elements (Garcia+, 2016)
J/AJ/151/49 : M6 open cluster: star members (Kilicoglu+, 2016)
J/ApJ/833/225 : -2.6≤[Fe/H]≤0.2 F & G dwarfs. II. Abund. (Zhao+, 2016)
J/A+A/603/A2 : Gaia-ESO Survey abund. radial distribution (Magrini+, 2017)
J/MNRAS/478/4513 : GALAH Survey DR2 (Buder+, 2018)
J/AJ/156/142 : Cluster abund. for APOGEE using SDSS DR14 (Donor+, 2018)
J/AJ/156/126 : Stellar abundances from BACCHUS analysis (Jonsson+, 2018)
J/A+A/628/A54 : Fe, Mg, Ti in Galactic clusters (Kovalev+, 2019)
J/A+A/622/A191 : 885 globular cluster giants abundances (Masseron+, 2019)
J/ApJS/244/27 : Radial velocity measurements in LAMOST-II (Wang+, 2019)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- --- [LAMOST_]
8- 26 A19 --- LAMOST LAMOST identifier (JHHMMSS.ss+DDMMSS.s)
28- 46 A19 --- Gaia Gaia DR2 identifier from cross-match
48- 94 A47 --- spIDv LAMOST spectral ID (inform of Date,
PlateID, SpectrographID, FiberID, MJM,
PiplineVersion)
96- 142 A47 --- spID_blue LAMOST spectral ID for the blue part
144- 190 A47 --- spID_red LAMOST spectral ID for the red part
192- 202 F11.7 deg RAdeg Right ascension (J2000)
204- 213 F10.7 deg DEdeg [-10/79.1] Declination (J2000)
215- 220 F6.2 --- S/N_blue [10/722] Signal-to-noise ratio of the
blue part
222- 227 F6.2 --- S/N_red [10/801] Signal-to-noise ratio of the red
part
229- 235 F7.2 km/s RV_blue [-572/571] Uncalibrated radial velocity
of the blue part
237- 243 F7.2 km/s RV_red [-576/618] Uncalibrated radial velocity
of the red part
245- 251 F7.2 K Teff [3587/7983] Effective temperature
253- 256 F4.2 [cm/s2] logg [0.6/5.5] Log of surface gravity
258- 267 F10.4 [Sun] [Fe/H] [-1.92/0.35]?=-9999 Iron abundance with
respect to hydrogen
269- 278 F10.4 [Sun] [C/H] [-1.49/0.85]?=-9999 Carbon abundance with
respect to hydrogen
280- 289 F10.4 [Sun] [N/H] [-1.17/0.46]?=-9999 Nitrogen abundance
with respect to hydrogen
291- 300 F10.4 [Sun] [O/H] [-1.67/0.5]?=-9999 Oxygen abundance with
respect to hydrogen
302- 311 F10.4 [Sun] [Mg/H] [-1.9/0.68]?=-9999 Magnesium abundance
with respect to hydrogen
313- 322 F10.4 [Sun] [Al/H] [-1.32/0.54]?=-9999 Aluminum abundance
with respect to hydrogen
324- 333 F10.4 [Sun] [Si/H] [-1.46/0.5]?=-9999 Silicon abundance
with respect to hydrogen
335- 344 F10.4 [Sun] [S/H] [-1.32/0.46]?=-9999 Sulfur abundance with
respect to hydrogen
346- 355 F10.4 [Sun] [Ca/H] [-1.45/0.49]?=-9999 Calcium abundance
with respect to hydrogen
357- 366 F10.4 [Sun] [Ti/H] [-1.73/0.56]?=-9999 Titanium abundance
with respect to hydrogen
368- 374 F7.4 [Sun] [Cr/H] [-1.45/0.52] Cadmium abundance with
respect to hydrogen
376- 385 F10.4 [Sun] [Ni/H] [-1.63/0.62]?=-9999 Nickel abundance with
respect to hydrogen
387- 396 F10.4 [Sun] [Cu/H] [-1.79/0.64]?=-9999 Copper abundance with
respect to hydrogen
398 I1 --- Qual Quality flag: 1=good, 0=bad
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History:
Downloaded from: http://doi.org/10.12149/101012
(End) Emmanuelle Perret [CDS] 05-Aug-2021