摘要：Data from the SDSS-IV/Apache Point Observatory Galactic Evolution Experiment (APOGEE-2) have beenreleased as part of SDSS Data Releases 13 (DR13) and 14 (DR14). These include high-resolution H-band spectra,radial velocities, and derived stellar parameters and abundances. DR13, released in 2016 August, containedAPOGEE data for roughly 150,000 stars, and DR14, released in 2017 August, added about 110,000 more. Stellarparameters and abundances have been derived with an automated pipeline, the APOGEE Stellar Parameter andChemical Abundance Pipeline (ASPCAP). We evaluate the performance of this pipeline by comparing the derivedstellar parameters and abundances to those inferred from optical spectra and analysis for several hundred stars. Formost elements—C, Na, Mg, Al, Si, S, Ca, Cr, Mn, Ni—the DR14 ASPCAP analyses have systematic differenceswith the comparisons samples of less than 0.05 dex (median), and random differences of less than 0.15 dex(standard deviation). These differences are a combination of the uncertainties in both the comparison samples aswell as the ASPCAP analysis. Compared to the references, magnesium is the most accurate alpha-element derivedby ASPCAP, and shows a very clear thin/thick disk separation, while nickel is the most accurate iron-peakelement (besides iron itself).
