The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III

TL;DR

The SDSS-III first data release provides extensive imaging and spectroscopic data, including improved processing and calibration, enabling advanced studies of Galactic structure, chemical evolution, and large-scale cosmic features.

Contribution

This paper presents the first data release of SDSS-III with significant improvements in data processing, calibration, and expanded coverage, supporting diverse astronomical research.

Findings

Imaging of 5200 deg^2 in the Southern Galactic Cap.

Spectroscopy of approximately 118,000 stars from SEGUE-2.

Reprocessed over half a million stellar spectra with improved parameters.

Abstract

The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly alpha forest, and a radial velocity search for planets around ~8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent photometric recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic Understanding and Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars at both high and low Galactic latitudes. All the more than half a million stellar spectra obtained with the SDSS spectrograph have been reprocessed through an improved stellar parameters pipeline, which has better determination of metallicity for high metallicity stars.