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A Time Delay for the Cluster-lensed Quasar SDSS J1004+4112

Fohlmeister, J. and Kochanek, C. S. and Falco, E. E. and Wambsganss, J. and Morgan, N. and Morgan, C. W. and Ofek, E. and Maoz, D. and Keeton, C. R. and Barentine, J. C. and Dalton, G. and Dembicky, J. and Ketzeback, W. and McMillan, R. and Peters, C. S. (2007) A Time Delay for the Cluster-lensed Quasar SDSS J1004+4112. Astrophysical Journal, 662 (1). pp. 62-71. ISSN 0004-637X. doi:10.1086/518018.

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We present 426 epochs of optical monitoring data spanning 1000 days from 2003 December to 2006 June for the gravitationally lensed quasar SDSS J1004+4112. The time delay between the A and B images is ΔtBA = 38:4 ± 2:0 days (Δχ^2 = 4) in the expected sense that B leads A and the overall time ordering is C-B-A-D-E. The measured delay invalidates all published models. The models probably failed because they neglected the perturbations from cluster member galaxies. Models including the galaxies can fit the data well, but conclusions about the cluster mass distribution should await the measurement of the longer, and less substructure sensitive, delays of the C and D images. For these images, a delay of ΔtCB ≃ 681 ± 15 days is plausible but requires confirmation, while delays of ΔtCB > 560 days and ΔtAD > 800 days are required. We clearly detect microlensing of the A/B images, with the delay-corrected flux ratios changing from mB - mA = 0:44 ± 0:01 mag in the first season to 0:29 ± 0:01 mag in the second season and 0:32 ± 0:01 mag in the third season.

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Kochanek, C. S.0000-0001-6017-2961
Ofek, E.0000-0002-6786-8774
Additional Information:© 2007. The American Astronomical Society. Received 2006 July 23; accepted 2007 March 5. We thank the Smithsonian Astrophysical Observatory (SAO) and all their participating observers for the support of our observations. This work is based on observations obtained with the Apache Point Observatory 3.5 m telescope, which is owned and operated by the Astrophysical Research Consortium. We thank E. Turner for organizing the APO observations. This work is also based on observations obtained with the MDM 2.4 m Hiltner and 1.3 m McGraw-Hill telescopes, which are owned and operated by a consortium consisting of Columbia University, Dartmouth College, the University of Michigan, the Ohio State University, and Ohio University. We would like to thank J. Halpern, J. Patterson, and S. Tuttle of Columbia University, D. Depoy, J. Eastman, S. Frank, J. Marshall, J. Prieto, K. Stanek, and D. Terndrup of OSU, and J. R. Thorstensen of Dartmouth College for their observations of this system. Observations for this project at Wise Observatory were supported by grants from the German-Israeli Foundation for Research and Development and the Israel Science Foundation. The WIYN Observatory is owned and operated by the WIYN Consortium, which consists of the University of Wisconsin, Indiana University, Yale University, and the National Optical Astronomy Observatory (NOAO). This work is based in part on observations made with the NASA/ESA Hubble Space Telescope as part of programs HST-GO-9744, HST-GO-10509, and HST-GO-10716 of the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. We also acknowledge support by the European Community's Sixth Framework Marie Curie Research Training Network Programme, contract MRTN-CT-2004-505183 “ANGLES.”
Funding AgencyGrant Number
Astrophysical Research ConsortiumUNSPECIFIED
Columbia UniversityUNSPECIFIED
Dartmouth CollegeUNSPECIFIED
University of MichiganUNSPECIFIED
Ohio State UniversityUNSPECIFIED
Ohio UniversityUNSPECIFIED
German-Israeli Foundation for Research and DevelopmentUNSPECIFIED
Israel Science FoundationUNSPECIFIED
European CommunityMRTN-CT-2004-505183 “ANGLES”
Space Telescope Science InstituteUNSPECIFIED
Subject Keywords:cosmology: observations—gravitational lensing—quasars: individual (SDSS J1004+4112)
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ID Code:12745
Deposited By: Archive Administrator
Deposited On:22 Dec 2008 19:06
Last Modified:08 Nov 2021 22:32

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