The Eighth Data Release of the Sloan Digital Sky Survey: First Data From SDSS-Iii

Abstract

The Sloan Digital Sky Survey (SDSS) started a new phase in 2008 August, 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 Lyα 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 Exploration (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 parameter pipeline, which has better determination of metallicity for high-metallicity stars.

TheXMM-Newtonserendipitous survey

“…This release contains point and compact source data extracted from HRC images as well as available ACIS data public at the end of 2009. ACDS accesses the Chandra source catalogue using the VO cone search protocol; ii) the Chandra ACIS survey in 383 nearby galaxies (Liu 2011); iii) the SDSS Photometric Catalog, Release 8 (Aihara et al 2011);…”

The masses of satellites in GAMA galaxy groups from 100 square degrees of KiDS weak lensing data

“…Individual exposures were regridded and co-added using a weighted mean procedure. Photometric zero-points were first derived per CCD by comparing nightly standard star observations to SDSS DR8 (Aihara et al 2011) and zero-point offsets were subsequently applied to the gri data, based on a comparison of the photometry between the CCDs in the five exposures. This yields a homogeneous photometry over 1 deg 2 .…”

NEW HIGH-z FERMI BL LACS WITH THE PHOTOMETRIC DROPOUT TECHNIQUE

“…The point-spread function (PSF) photometric technique was used for ¢ ¢ ¢ ¢ g r i z , , , filters, whereas, due to the undersampled PSF in the near-infrared, the standard aperture extraction technique was applied for J, H, K s photometry. The fouroptical filters were calibrated with the stars in the SDSS Data Release 8 (Aihara et al 2011), which provides the final magnitudes in the AB system. 2MASS stars (Skrutskie et al 2006) were employed for calibration of the near-IR filters.…”