The SDSS u-band Galaxy Survey (uGS) and other Southern Survey data

Date release

The SDSS u-band Galaxy Survey (uGS) consists of high signal-to-noise ratio (S/N) magnitude measurements using a coadded catalog, sky-subtraction corrections to u-band Petrosian magnitudes, and spectra selected in a variety of ways with completeness corrections for u-band selected samples. It is part of the Southern Survey region: RA from -50.8 to 58.6 and DEC from -1.26 to 1.26 (an area of 275 square degrees). See the SDSS uGS paper for details (MNRAS, 358, 441).

The following files contain the data for the coadded uGS catalog with additional selection. The catalog combines a u < 21 and r < 19 resolved-object sample (r_psf - r_model > 0.05). Thus it includes both blue- and red-sequence normal galaxies to z~0.4 (and quasars to higher redshift, and some stars). The photometric catalog includes 182646 objects; and the spectroscopic catalog includes 68745 objects (of which, 40208 are Southern program targets). The following figure illustrates the demographics of the spectroscopic catalog:

Links to files:
matchObj-[yymmdd].fits.gz
matchObj-SJ-[yymmdd].fits.gz (match to Scranton & Johnston's catalog)
deriveObj-[yymmdd].fits.gz
spmatchPton-[yymmdd].fits.gz
spmatchFlab-[yymmdd].fits.gz
spmatchMPA-[yymmdd].fits.gz (match to MPA Garching DR4 catalog)
spmatchMPA-[yymmdd].fits.gz (NEW: match to MPA Garching DR7 catalog, mpa_index to 927552 objects in original, not complete, missing SFR, metallicity)
all files

Links to data-model information:
Data model for matchObj.fits (photometric catalog: coadded fluxes, positions and other data, including the standard tsobj flags, for the matched objects in the catalog)
Data model for deriveObj.fits (photometric catalog additional data: including corrected Petrosian counts that were used for object selection; and spectroscopic completeness corrections)
Data model for spmatchPton.fits (spectroscopic catalog using Princeton reductions)
Data model for spmatchFlab.fits (spectroscopic catalog using Fermilab reductions)
Data model for spmatchMPA.fits (spectroscopic catalog match to MPA Garching reductions)

Links to other Southern Survey webpages:
SDSS uGS and other Southern Surveys (more information on targeting and plates; Baldry);
Southern Survey Proposals; (Annis)
Southern Equatorial Survey Plates (Lin);
Southern Mailing List (many authors);
Catalog-level coadds for stripe 82 (Scranton & Johnston);
Magnitudes in the Image Coadd (Annis).

Acknowledgements: Thanks to Michael Blanton (k-correction code), Jarle Brinchmann, Tamas Budavari, Karl Glazebrook and the Southern Survey working group (Huan Lin, Jim Annis for low-z target selection; and others).

Page created by Ivan Baldry, Liverpool JMU, written 2005 June 2nd, last updated 2008 July 16th. If you wish to use these data, please send me an email for updates, suggestions, collaboration etc.