THE ELEVENTH AND TWELFTH DATA RELEASES OF THE SLOAN DIGITAL SKY SURVEY: FINAL DATA FROM SDSS-III

Abstract

The third generation of the Sloan Digital Sky Survey (SDSS-III) took data\nfrom 2008 to 2014 using the original SDSS wide-field imager, the original and\nan upgraded multi-object fiber-fed optical spectrograph, a new near-infrared\nhigh-resolution spectrograph, and a novel optical interferometer. All the data\nfrom SDSS-III are now made public. In particular, this paper describes Data\nRelease 11 (DR11) including all data acquired through 2013 July, and Data\nRelease 12 (DR12) adding data acquired through 2014 July (including all data\nincluded in previous data releases), marking the end of SDSS-III observing.\nRelative to our previous public release (DR10), DR12 adds one million new\nspectra of galaxies and quasars from the Baryon Oscillation Spectroscopic\nSurvey (BOSS) over an additional 3000 sq. deg of sky, more than triples the\nnumber of H-band spectra of stars as part of the Apache Point Observatory (APO)\nGalactic Evolution Experiment (APOGEE), and includes repeated accurate radial\nvelocity measurements of 5500 stars from the Multi-Object APO Radial Velocity\nExoplanet Large-area Survey (MARVELS). The APOGEE outputs now include measured\nabundances of 15 different elements for each star. In total, SDSS-III added\n2350 sq. deg of ugriz imaging; 155,520 spectra of 138,099 stars as part of the\nSloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey;\n2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216\nstars over 9376 sq. deg; 618,080 APOGEE spectra of 156,593 stars; and 197,040\nMARVELS spectra of 5,513 stars. Since its first light in 1998, SDSS has imaged\nover 1/3 of the Celestial sphere in five bands and obtained over five million\nastronomical spectra.\n