A PRECISION MULTI- BAND TWO-EPOCH PHOTOMETRIC CATALOG OF 44 MILLION SOURCES IN THE NORTHERN SKY FROM A COMBINATION OF THE USNO-B AND SLOAN DIGITAL SKY SURVEY CATALOGS

作者：Madsen G J^*; Gaensler B M

来源：Astrophysical Journal, The - Supplement Series, 2013, 209(2).

DOI：10.1088/0067-0049/209/2/33

• catalogs
• methods: data analysis
• quasars: general
• stars: variables: general
• techniques: photometric

A key science driver for the next generation of wide-field optical and radio surveys is the exploration of the time variable sky. These surveys will have unprecedented sensitivity and areal coverage, but will be limited in their ability to detect variability on time scales longer than the lifetime of the surveys. We present a new precision, multi-epoch photometric catalog that spans 60 yr by combining the US Naval Observatory-B (USNO-B) and Sloan Digital Sky Survey (SDSS) Data Release 9 (DR9) catalogs. We recalibrate the photometry of the original USNO-B catalog and create a catalog with two epochs of photometry in up to five different bands for 43,647,887 optical point sources that lie in the DR9 footprint of the northern sky. The recalibrated objects span a magnitude range 14 less than or similar to m less than or similar to 20 and are accurate to approximate to 0.1 mag. We minimize the presence of spurious objects and those with inaccurate magnitudes by identifying and removing several sources of systematic errors in the two originating catalogs, with a focus on spurious objects that exhibit large apparent magnitude variations. After accounting for these effects, we find approximate to 250,000 stars and quasars that show significant (>= 4 sigma) changes in brightness between the USNO-B and SDSS DR9 epochs. We discuss the historical value of the catalog and its application to the study of long time scale, large amplitude variable stars and quasars.

• 出版日期2013-12