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dc.contributor.authorDiPompeo, M. A.
dc.contributor.authorMyers, A. D.
dc.contributor.authorHickox, R. C.
dc.contributor.authorGeach, J. E.
dc.contributor.authorHainline, K. N.
dc.date.accessioned2017-09-15T14:09:56Z
dc.date.available2017-09-15T14:09:56Z
dc.date.issued2014-08-21
dc.identifier.citationDiPompeo , M A , Myers , A D , Hickox , R C , Geach , J E & Hainline , K N 2014 , ' The angular clustering of infrared-selected obscured and unobscured quasars ' , Monthly Notices of the Royal Astronomical Society , vol. 442 , no. 4 , stu1115 , pp. 3443-3453 . https://doi.org/10.1093/mnras/stu1115
dc.identifier.issn0035-8711
dc.identifier.otherPURE: 11127120
dc.identifier.otherPURE UUID: 1cbf4a63-82d7-4a37-a306-f232e327ca56
dc.identifier.otherScopus: 84904582685
dc.identifier.urihttp://hdl.handle.net/2299/19424
dc.descriptionThis article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. ©: 2014 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
dc.description.abstractRecent studies of luminous infrared-selected active galactic nuclei (AGN) suggest that the reddest, most obscured objects display a higher angular clustering amplitude, and thus reside in higher mass darkmatter haloes. This is a direct contradiction to the prediction of the simplest unification-by-orientation models of AGN and quasars. However, clustering measurements depend strongly on the 'mask' that removes low-quality data and describes the sky and selection function.We find that applying a robust, conservative mask to WISE-selected quasars yields a weaker but still significant difference in the bias between obscured and unobscured quasars. These findings are consistent with results from previous Spitzer surveys, and removes any scale dependence of the bias. For obscured quasars with <z> =0.99, we measure a bias of bq = 2.67 ± 0.16, corresponding to a halo mass of log(Mh/M⊙h-1) = 13.3 ± 0.1, while for unobscured sources with <z> = 1.04 we find bq = 2.04 ± 0.17 with a halo mass log(Mh/M⊙h-1) = 12.8 ± 0.1. This improved measurement indicates that WISE-selected obscured quasars reside in haloes only a few times more massive than the haloes of their unobscured counterparts, a reduction in the factor of ∼10 larger halo mass as has been previously reported using WISE-selected samples. Additionally, an abundance matching analysis yields lifetimes for both obscured and unobscured quasar phases on the order of a few 100 Myr (∼1 per cent of the Hubble time) - however, the obscured phase lasts roughly twice as long, in tension with many model predictions.en
dc.format.extent11
dc.language.isoeng
dc.relation.ispartofMonthly Notices of the Royal Astronomical Society
dc.subjectEvolution
dc.subjectGalaxies
dc.subjectGalaxies active
dc.subjectQuasars general
dc.subjectAstronomy and Astrophysics
dc.subjectSpace and Planetary Science
dc.titleThe angular clustering of infrared-selected obscured and unobscured quasarsen
dc.contributor.institutionCentre for Astrophysics Research
dc.contributor.institutionUniversity of Hertfordshire
dc.description.statusPeer reviewed
dc.identifier.urlhttp://www.scopus.com/inward/record.url?scp=84904582685&partnerID=8YFLogxK
rioxxterms.versionVoR
rioxxterms.versionofrecordhttps://doi.org/10.1093/mnras/stu1115
rioxxterms.typeJournal Article/Review
herts.preservation.rarelyaccessedtrue


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