A neural network trained on simulations infers stripping times for Sagittarius stream stars from phase-space data, measuring a 0.3 dex/Gyr metallicity gradient and estimating ages for globular clusters such as Pal 12 and NGC 2419.
ASPCAP: The Apogee Stellar Parameter and Chemical Abundances Pipeline
3 Pith papers cite this work. Polarity classification is still indexing.
abstract
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has built the largest moderately high-resolution (R=22, 500) 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 chi-2 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%, 0.1 dex, and 0.05 dex, 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 0.1 dex. 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.
years
2026 3verdicts
UNVERDICTED 3representative citing papers
High [Si/Mg] = 0.67 in NGC 1277 cannot be explained by standard models and suggests pair-instability supernovae from very massive early stars.
Observational study of 290 exoplanet-host stars finds higher C, O, S, Fe, Ni abundances in giant-planet hosts than small-planet hosts, with C/O ratios, hot/warm differences, and mass correlations that vary by subpopulation.
citing papers explorer
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Reconstructing the Stripping History of the Sagittarius Stream with Neural Networks
A neural network trained on simulations infers stripping times for Sagittarius stream stars from phase-space data, measuring a 0.3 dex/Gyr metallicity gradient and estimating ages for globular clusters such as Pal 12 and NGC 2419.
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Chemical hints of Population III stars from silicon abundances in massive galaxies
High [Si/Mg] = 0.67 in NGC 1277 cannot be explained by standard models and suggests pair-instability supernovae from very massive early stars.
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Chemical Abundances of the Bioessential Elements C, O and S, and the Refractory Elements Fe and Ni, in Solar-type Exoplanet-hosting Stars from HARPS North and South
Observational study of 290 exoplanet-host stars finds higher C, O, S, Fe, Ni abundances in giant-planet hosts than small-planet hosts, with C/O ratios, hot/warm differences, and mass correlations that vary by subpopulation.