A Galaxy Photometric Redshift Catalog for the Sloan Digital Sky Survey Data Release 6
- 20 February 2008
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 674 (2) , 768-783
- https://doi.org/10.1086/523666
Abstract
We present and describe a catalog of galaxy photometric redshifts (photo-z's) for the Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6). We use the Artificial Neural Network (ANN) technique to calculate photo-z's and the Nearest Neighbor Error (NNE) method to estimate photo-z errors for ~ 77 million objects classified as galaxies in DR6 with r < 22. The photo-z and photo-z error estimators are trained and validated on a sample of ~ 640,000 galaxies that have SDSS photometry and spectroscopic redshifts measured by SDSS, 2SLAQ, CFRS, CNOC2, TKRS, DEEP, and DEEP2. For the two best ANN methods we have tried, we find that 68% of the galaxies in the validation set have a photo-z error smaller than sigma_{68} =0.021 or $0.024. After presenting our results and quality tests, we provide a short guide for users accessing the public data.Comment: 16 pages, 12 figureKeywords
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This publication has 35 references indexed in Scilit:
- The Fifth Data Release of the Sloan Digital Sky SurveyThe Astrophysical Journal Supplement Series, 2007
- The 2dF-SDSS LRG and QSO (2SLAQ) Luminous Red Galaxy SurveyMonthly Notices of the Royal Astronomical Society, 2006
- The Fourth Data Release of the Sloan Digital Sky SurveyThe Astrophysical Journal Supplement Series, 2006
- The Second Data Release of the Sloan Digital Sky SurveyThe Astronomical Journal, 2004
- ANNz: Estimating Photometric Redshifts Using Artificial Neural NetworksPublications of the Astronomical Society of the Pacific, 2004
- An Efficient Targeting Strategy for Multiobject Spectrograph Surveys: the Sloan Digital Sky Survey “Tiling” AlgorithmThe Astronomical Journal, 2003
- The Application of Photometric Redshifts to the SDSS Early Data ReleaseThe Astronomical Journal, 2003
- SExtractor: Software for source extractionAstronomy and Astrophysics Supplement Series, 1996
- Slicing Through Multicolor Space: Galaxy Redshifts from Broadband PhotometryThe Astronomical Journal, 1995
- Colors and magnitudes predicted for high redshift galaxiesThe Astrophysical Journal Supplement Series, 1980