Value Added Catalogs

In addition to the primary SDSS photometry and spectroscopy, there are a few extra catalogs created by our collaborators that are distributed through the SAS. These Value-Added Catalogs (VACs) are listed below, and include catalogs that were released in earlier data releases.

Photometric Redshift Distributions

Scientific Analysis Catalog

Redshift probability distributions derived with weighting techniques for photometrically detected galaxies.

Erin S. Sheldon, Carlos E. Cunha, Rachel Mandelbaum, J. Brinkmann, Benjamin A. Weaver


This catalog contains a set of photometric redshift probability distributions for galaxies in the SDSS-III imaging data. We derived weights for a training set of spectroscopically confirmed galaxies such that the distribution of relevant quantities, such as magnitudes or colors, matches that of a set of galaxies without known redshifts (the photometric sample). Assuming these quantities correlate with redshift, and are the only relevant quantities for redshift determination, the resulting weighted redshift histogram is proportional to the redshift distribution of the photometric sample. This technique is also used to derive the redshift probability distribution for individual galaxies. For more details, see Sheldon et al. (2012).

Catalog last modified: 2021-12-06 07:36:54

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