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dc.contributor.authorBilicki, Maciej
dc.contributor.authorPeacock, John A.
dc.contributor.authorJarrett, Thomas H.
dc.contributor.authorCluver, Michelle E.
dc.contributor.authorMaddox, Natasha
dc.contributor.authorBrown, Michael J. I.
dc.contributor.authorTaylor, Edward N.
dc.contributor.authorHambly, Nigel C.
dc.contributor.authorSolarz, Aleksandra
dc.contributor.authorHolwerda, Benne W.
dc.contributor.authorBaldry, Ivan
dc.contributor.authorLoveday, Jon
dc.contributor.authorMoffett, Amanda
dc.contributor.authorHopkins, Andrew M.
dc.contributor.authorDriver, Simon P.
dc.contributor.authorAlpaslan, Mehmet
dc.contributor.authorBland-Hawthorn, Joss
dc.identifier.citationBilicki , M , Peacock , J A , Jarrett , T H , Cluver , M E , Maddox , N , Brown , M J I , Taylor , E N , Hambly , N C , Solarz , A , Holwerda , B W , Baldry , I , Loveday , J , Moffett , A , Hopkins , A M , Driver , S P , Alpaslan , M & Bland-Hawthorn , J 2016 , ' WISE × SuperCOSMOS photometric redshift catalog : 20 million Galaxies over 3π steradians ' , Astrophysical Journal Supplement Series , vol. 225 , no. 1 , 5 .
dc.identifier.otherPURE: 245053358
dc.identifier.otherPURE UUID: a1b40550-55a6-4b83-9378-7fe0623f8a21
dc.identifier.otherScopus: 84980322493
dc.identifier.otherWOS: 000382309000005
dc.descriptionM Bilicki was supported through FP7 grant number 279396 from the European Research Council.en
dc.description.abstractWe cross-match the two currently largest all-sky photometric catalogs - mid-infrared Wide-field Infrared Survey Explorer and SuperCOSMOS scans of UKST/POSS-II photographic plates - to obtain a new galaxy sample that covers 3π steradians. In order to characterize and purify the extragalactic data set, we use external GAMA and Sloan Digital Sky Survey spectroscopic information to define quasar and star loci in multicolor space, aiding the removal of contamination from our extended source catalog. After appropriate data cleaning, we obtain a deep wide-angle galaxy sample that is approximately 95% pure and 90% complete at high Galactic latitudes. The catalog contains close to 20 million galaxies over almost 70% of the sky, outside the Zone of Avoidance and other confused regions, with a mean surface density of more than 650 sources per square degree. Using multiwavelength information from two optical and two mid-IR photometric bands, we derive photometric redshifts for all the galaxies in the catalog, using the ANNz framework trained on the final GAMA-II spectroscopic data. Our sample has a median redshift of zmed = 0.2, with a broad dN/dz reaching up to z > 0.4. The photometric redshifts have a mean bias of |δz|, ∼ 10-3 a normalized scatter of σ z = 0.033, and less than 3% outliers beyond 3σ z. Comparison with external data sets shows no significant variation of photo-z quality with sky position. Together with the overall statistics, we also provide a more detailed analysis of photometric redshift accuracy as a function of magnitudes and colors. The final catalog is appropriate for "all-sky" three-dimensional (3D) cosmology to unprecedented depths, in particular through cross-correlations with other large-area surveys. It should also be useful for source preselection and identification in forthcoming surveys, such as TAIPAN or WALLABY.
dc.relation.ispartofAstrophysical Journal Supplement Seriesen
dc.rights© 2016. The American Astronomical Society. All rights reserved. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at:
dc.subjectGalaxies: distances and redshiftsen
dc.subjectLarge-scale structure of universeen
dc.subjectMethods: data analysisen
dc.subjectMethods: statisticalen
dc.subjectQB Astronomyen
dc.subjectQC Physicsen
dc.subjectSpace and Planetary Scienceen
dc.subjectAstronomy and Astrophysicsen
dc.titleWISE × SuperCOSMOS photometric redshift catalog : 20 million Galaxies over 3π steradiansen
dc.typeJournal articleen
dc.description.versionPublisher PDFen
dc.contributor.institutionUniversity of St Andrews.School of Physics and Astronomyen
dc.description.statusPeer revieweden

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