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dc.contributor.authorBlackburne, Jeffrey A.
dc.contributor.authorPooley, David
dc.contributor.authorSchechter, Paul L.
dc.contributor.authorRappaport, Saul A
dc.date.accessioned2012-08-06T15:20:23Z
dc.date.available2012-08-06T15:20:23Z
dc.date.issued2011-02
dc.date.submitted2010-07
dc.identifier.issn0004-637X
dc.identifier.issn1538-4357
dc.identifier.urihttp://hdl.handle.net/1721.1/71986
dc.description.abstractMicrolensing perturbations to the flux ratios of gravitationally lensed quasar images can vary with wavelength because of the chromatic dependence of the accretion disk's apparent size. Multiwavelength observations of microlensed quasars can thus constrain the temperature profiles of their accretion disks, a fundamental test of an important astrophysical process which is not currently possible using any other method. We present single-epoch broadband flux ratios for 12 quadruply lensed quasars in 8 bands ranging from 0.36 to 2.2 μm, as well as Chandra 0.5-8 keV flux ratios for five of them. We combine the optical/IR and X-ray ratios, together with X-ray ratios from the literature, using a Bayesian approach to constrain the half-light radii of the quasars in each filter. Comparing the overall disk sizes and wavelength slopes to those predicted by the standard thin accretion disk model, we find that on average the disks are larger than predicted by nearly an order of magnitude, with sizes that grow with wavelength with an average slope of ~0.2 rather than the slope of 4/3 predicted by the standard thin disk theory. Though the error bars on the slope are large for individual quasars, the large sample size lends weight to the overall result. Our results present severe difficulties for a standard thin accretion disk as the main source of UV/optical radiation from quasars.en_US
dc.description.sponsorshipNational Science Foundation (U.S.) (grant AST-0607601)en_US
dc.language.isoen_US
dc.publisherIOP Publishingen_US
dc.relation.isversionofhttp://dx.doi.org/10.1088/0004-637x/729/1/34en_US
dc.rightsCreative Commons Attribution-Noncommercial-Share Alike 3.0en_US
dc.rights.urihttp://creativecommons.org/licenses/by-nc-sa/3.0/en_US
dc.sourceProf. Schechter via Mat Willmotten_US
dc.titleSizes and Temperature Profiles of Quasar Accretion Disks from Chromatic Microlensingen_US
dc.typeArticleen_US
dc.identifier.citationBlackburne, Jeffrey A. et al. “Sizes and Temperature Profiles of Quasar Accretion Disks from Chromatic Microlensing.” The Astrophysical Journal 729.1 (2011): 34.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Physicsen_US
dc.contributor.departmentMIT Kavli Institute for Astrophysics and Space Researchen_US
dc.contributor.approverSchechter, Paul L.
dc.contributor.mitauthorBlackburne, Jeffrey A.
dc.contributor.mitauthorRappaport, Saul A.
dc.contributor.mitauthorSchechter, Paul L.
dc.relation.journalAstrophysical Journalen_US
dc.eprint.versionAuthor's final manuscripten_US
dc.type.urihttp://purl.org/eprint/type/JournalArticleen_US
eprint.statushttp://purl.org/eprint/status/PeerRevieweden_US
dspace.orderedauthorsBlackburne, Jeffrey A.; Pooley, David; Rappaport, Saul; Schechter, Paul L.en
dc.identifier.orcidhttps://orcid.org/0000-0002-5665-4172
dc.identifier.orcidhttps://orcid.org/0000-0003-3182-5569
mit.licenseOPEN_ACCESS_POLICYen_US


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