J/AJ/151/144 ASPCAP weights for the 15 APOGEE chemical elements (Garcia+, 2016)
ASPCAP: the APOGEE Stellar Parameter and Chemical Abundances Pipeline.
Garcia Perez A.E., Allende Prieto C., Holtzman J.A., Shetrone M.,
Meszaros S., Bizyaev D., Carrera R., Cunha K., Garcia-Hernandez D.A.,
Johnson J.A., Majewski S.R., Nidever D.L., Schiavon R.P., Shane N.,
Smith V.V., Sobeck J., Troup N., Zamora O., Weinberg D.H., Bovy J.,
Eisenstein D.J., Feuillet D., Frinchaboy P.M., Hayden M.R., Hearty F.R.,
Nguyen D.C., O'Connell R.W., Pinsonneault M.H., Wilson J.C., Zasowski G.
<Astron. J., 151, 144-144 (2016)>
=2016AJ....151..144G 2016AJ....151..144G (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Abundances
Keywords: Galaxy: center - Galaxy: structure - methods: data analysis -
stars: abundances - stars: atmospheres
Abstract:
The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
has built the largest moderately high-resolution (R∼22500)
spectroscopic map of the stars across the Milky Way, and including
dust-obscured areas. The APOGEE Stellar Parameter and Chemical
Abundances Pipeline (ASPCAP) is the software developed for the
automated analysis of these spectra. ASPCAP determines atmospheric
parameters and chemical abundances from observed spectra by comparing
observed spectra to libraries of theoretical spectra, using χ2
minimization in a multidimensional parameter space. The package
consists of a fortran90 code that does the actual minimization and a
wrapper IDL code for book-keeping and data handling. This paper
explains in detail the ASPCAP components and functionality, and
presents results from a number of tests designed to check its
performance. ASPCAP provides stellar effective temperatures, surface
gravities, and metallicities precise to 2%, 0.1dex, and 0.05dex,
respectively, for most APOGEE stars, which are predominantly giants.
It also provides abundances for up to 15 chemical elements with
various levels of precision, typically under 0.1dex. The final data
release (DR12) of the Sloan Digital Sky Survey III contains an APOGEE
database of more than 150,000 stars. ASPCAP development continues in
the SDSS-IV APOGEE-2 survey.
Description:
The Apache Point Observatory Galactic Evolution Experiment (APOGEE)
has built the largest moderately high-resolution (R∼22500)
spectroscopic map of the stars across the Milky Way, and including
dust-obscured areas.
The APOGEE Stellar Parameter and Chemical Abundances Pipeline (ASPCAP)
is the software developed for the automated analysis of these spectra.
The pipeline matches the observations to a set of synthetic spectrum
templates using the χ2 minimization in a multidimensional
parameter space. Stellar parameters are derived first from the entire
APOGEE spectral range, followed by the determination of individual
chemical abundances from spectral windows optimized for each element.
Table3 gives the weights as a function of wavelength, for the 15
APOGEE chemical elements.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 179 7214 ASPCAP spectral windows for chemical abundances
determinations
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See also:
J/ApJS/221/24 : SDSS-III APOGEE H-band spectral line lists (Shetrone+, 2015)
J/AJ/146/133 : Stellar parameters from SDSS-III APOGEE DR10 (Meszaros+, 2013)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 14 F14.12 um lambda [1.5/1.7] Wavelength λ (1)
16- 25 F10.8 --- Fe [0/0.68] Iron abundance weight
27- 36 F10.8 --- C [0/0.6] Carbon abundance weight
38- 47 F10.8 --- N [0/0.6] Nitrogen abundance weight
49- 58 F10.8 --- O [0/0.67] Oxygen abundance weight
60- 69 F10.8 --- Na [0/0.57] Sodium abundance weight
71- 80 F10.8 --- Mg [0/0.29] Magnesium abundance weight
82- 91 F10.8 --- Al [0/0.75] Aluminum abundance weight
93-102 F10.8 --- Si [0/0.71] Silicon abundance weight
104-113 F10.8 --- S [0/0.6] Sulfur abundance weight
115-124 F10.8 --- K [0/0.84] Potassium abundance weight
126-135 F10.8 --- Ca [0/0.88] Calcium abundance weight
137-146 F10.8 --- Ti [0/0.9] Titanium abundance weight
148-157 F10.8 --- V [0/0.58] Vanadium abundance weight
159-168 F10.8 --- Mn [0/0.88] Manganese abundance weight
170-179 F10.8 --- Ni [0/0.55] Nickel abundance weight
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Note (1): Three spectral regions, which correspond to the spectral coverage of
the three APOGEE detectors, are synthesized: λ=1.51681-1.57923µm,
1.58814-1.64166µm, and 1.64995-1.69367µm (vacuum wavelengths).
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 19-Jul-2016