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J/ApJ/862/12     Photometric Redshift Catalog (SCUSS, SDSS, WISE)   (Gao+, 2018)

A photometric redshift catalog based on SCUSS, SDSS and WISE surveys. Gao J., Zou H., Zhou X., Kong X. <Astrophys. J. 862, 12 (2018)> =2018ApJ...862...12G (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Redshifts ; Surveys Keywords: galaxies: clusters: general - galaxies: distances and redshifts - galaxies: photometry Abstract: We publish a photometric redshift catalog based on imaging data of the South Galactic Cap u-band Sky Survey, Sloan Digital Sky Survey (SDSS), and Wide-field Infrared Survey Explorer (WISE). A total of 7 photometric bands are used, ranging from near ultraviolet to near infrared. A local linear regression method is adopted to estimate the photometric redshift with a dedicated spectroscopic training set. The photometric redshift catalog contains about 23.1 million galaxies classified by SDSS. Using the training set with redshift up to 0.8 and r-band magnitude down to 22mag, we achieve an average bias of Δznorm=0.000228, standard deviation of σ(Δznorm)=0.019, and 3σ outlier rate of about 4.2%. The bias is less than 0.01 at z<0.6 and goes up to about 0.05 at z∼0.8. Compared with SDSS photometric redshifts, our redshift estimations are more accurate and have less bias. Description: Our photometric redshift catalog is based on SDSS galaxies with r-band positive model flux measurements. The source type is from the SDSS star/galaxy separation. The photometric redshift accuracy is dependent on the photometric error, number of used filters, and completeness of the training set. In our catalog, we only provide the photometric redshifts for galaxies with r<22mag and at least 5 filters with colors within color cuts. Larger photometric errors and fewer colors give much more catastrophic redshift estimations. There are total 23,067,608 galaxies with these constraints. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file scussphz.dat 237 23067608 Photometric redshifts of galaxies
See also: II/311 : WISE All-Sky Data Release (Cutri+ 2012) V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015) Byte-by-byte Description of file: scussphz.dat
Bytes Format Units Label Explanations
1- 19 I19 --- objID SDSS photometric object ID 21- 22 I2 --- Nn Number of the neighbors used for estimating the photometric redshift 24 I1 --- Nf Number of filters having r<22mag and colors within color cuts 26- 34 F9.5 deg RAdeg Right ascension (J2000) 36- 43 F8.5 deg DEdeg Declination (J2000) 45- 51 F7.3 --- zspec ?=-10 Spectroscopic redshift if exist 53- 58 F6.3 --- zphot Estimated photometric redshift by the local linear regression model 60- 64 F5.3 --- e_zphot Estimated error for the photometric redshift 66- 71 F6.3 --- zbias Bias of the photometric redshift estimated by the neighbors 73- 77 F5.3 --- zmean Average spectroscopic redshift of the neighbors 79- 83 F5.3 --- zneareast Spectroscopic redshift of the nearest neighbor in the multi-dimension color space 85- 89 F5.3 --- meanDist Average Euclidean distance of neighbors in the multi-dimension color space 91- 97 F7.4 mag u*magmod ?=99 SCUSS u-band model magnitude 99-105 F7.4 mag umagmod ?=99 SDSS u-band model magnitude 107-113 F7.4 mag gmagmod ?=99 SDSS g-band model magnitude 115-121 F7.4 mag rmagmod ?=99 SDSS r-band model magnitude 123-129 F7.4 mag imagmod ?=99 SDSS i-band model magnitude 131-137 F7.4 mag zmagmod ?=99 SDSS z-band model magnitude 139-145 F7.4 mag W1magmod ?=99 WISE W 1 model magnitude 147-153 F7.4 mag W2magmod ?=99 WISE W 2 model magnitude 155-161 F7.4 mag e_u*magmod ?=99 SCUSS u-band model magnitude error 163-172 F10.4 mag e_umagmod ?=99 SDSS u-band model magnitude error 174-183 F10.4 mag e_gmagmod ?=99 SDSS g-band model magnitude error 185-191 F7.4 mag e_rmagmod ?=99 SDSS r-band model magnitude error 193-202 F10.4 mag e_imagmod ?=99 SDSS i-band model magnitude error 204-213 F10.4 mag e_zmagmod ?=99 SDSS z-band model magnitude error 215-225 F11.4 mag e_W1magmod ?=99 WISE W1 model magnitude error 227-237 F11.4 mag e_W2magmod ?=99 WISE W2 model magnitude error
Acknowledgements: Hu Zou, zouhu(at)nao.cas.cn
(End) Jinghua Gao [NAOC, China], Patricia Vannier [CDS] 09-Jul-2018
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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