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Title: LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745

Abstract

SDSS J2222+2745 is a galaxy cluster at z = 0.49, strongly lensing a quasar at z = 2.805 into six widely separated images. In recent Hubble Space Telescope imaging of the field, we identify additional multiply lensed galaxies and confirm the sixth quasar image that was identified by Dahle et al. We used the Gemini-North telescope to measure a spectroscopic redshift of z = 4.56 of one of the lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image of the quasar host and a lensed galaxy at z = 2.3. This galaxy also appears in absorption in our Gemini spectra of the lensed quasar, at a projected distance of 34 kpc. Our model is in agreement with the recent time delay measurements of Dahle et al., who found τ {sub AB} = 47.7 ± 6.0 days and τ {sub AC} = −722 ± 24 days. We use the observed time delays to further constrain the model, and find that the model-predicted time delays of the three faint images of the quasar are τ {sub AD} = 502 ± 68more » days, τ {sub AE} = 611 ± 75 days, and τ {sub AF} = 415 ± 72 days. We have initiated a follow-up campaign to measure these time delays with Gemini North. Finally, we present initial results from an X-ray monitoring program with Swift , indicating the presence of hard X-ray emission from the lensed quasar, as well as extended X-ray emission from the cluster itself, which is consistent with the lensing mass measurement and the cluster velocity dispersion.« less

Authors:
; ;  [1];  [2];  [3]; ;  [4];  [5];  [6];  [7]
  1. Department of Astronomy, University of Michigan, 1085 S. University Avenue, Ann Arbor, MI 48109 (United States)
  2. Colby College, 5800 Mayflower Hill, Waterville, 04901, Maine (United States)
  3. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, NO-0315 Oslo (Norway)
  4. Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)
  5. Astrophysics Science Division, Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States)
  6. Department of Astronomy, University of Massachusetts-Amherst, Amherst, MA 01003 (United States)
  7. Max-Planck-Institut für extraterrestrische Physik, Giessenbachstr. 1, D-85741 Garching (Germany)
Publication Date:
OSTI Identifier:
22664027
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABSORPTION; DISPERSIONS; EMISSION; GALAXIES; GALAXY CLUSTERS; GRAVITATIONAL LENSES; HARD X RADIATION; MASS; QUASARS; RED SHIFT; SPACE; SPECTRA; TELESCOPES; TIME DELAY; VELOCITY

Citation Formats

Sharon, Keren, Johnson, Traci L., Paterno-Mahler, Rachel, Bayliss, Matthew B., Dahle, Håkon, Florian, Michael K., Gladders, Michael D., Rigby, Jane R., Whitaker, Katherine E., and Wuyts, Eva, E-mail: kerens@umich.edu. LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/1/5.
Sharon, Keren, Johnson, Traci L., Paterno-Mahler, Rachel, Bayliss, Matthew B., Dahle, Håkon, Florian, Michael K., Gladders, Michael D., Rigby, Jane R., Whitaker, Katherine E., & Wuyts, Eva, E-mail: kerens@umich.edu. LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745. United States. doi:10.3847/1538-4357/835/1/5.
Sharon, Keren, Johnson, Traci L., Paterno-Mahler, Rachel, Bayliss, Matthew B., Dahle, Håkon, Florian, Michael K., Gladders, Michael D., Rigby, Jane R., Whitaker, Katherine E., and Wuyts, Eva, E-mail: kerens@umich.edu. Fri . "LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745". United States. doi:10.3847/1538-4357/835/1/5.
@article{osti_22664027,
title = {LENS MODEL AND TIME DELAY PREDICTIONS FOR THE SEXTUPLY LENSED QUASAR SDSS J2222+2745},
author = {Sharon, Keren and Johnson, Traci L. and Paterno-Mahler, Rachel and Bayliss, Matthew B. and Dahle, Håkon and Florian, Michael K. and Gladders, Michael D. and Rigby, Jane R. and Whitaker, Katherine E. and Wuyts, Eva, E-mail: kerens@umich.edu},
abstractNote = {SDSS J2222+2745 is a galaxy cluster at z = 0.49, strongly lensing a quasar at z = 2.805 into six widely separated images. In recent Hubble Space Telescope imaging of the field, we identify additional multiply lensed galaxies and confirm the sixth quasar image that was identified by Dahle et al. We used the Gemini-North telescope to measure a spectroscopic redshift of z = 4.56 of one of the lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image of the quasar host and a lensed galaxy at z = 2.3. This galaxy also appears in absorption in our Gemini spectra of the lensed quasar, at a projected distance of 34 kpc. Our model is in agreement with the recent time delay measurements of Dahle et al., who found τ {sub AB} = 47.7 ± 6.0 days and τ {sub AC} = −722 ± 24 days. We use the observed time delays to further constrain the model, and find that the model-predicted time delays of the three faint images of the quasar are τ {sub AD} = 502 ± 68 days, τ {sub AE} = 611 ± 75 days, and τ {sub AF} = 415 ± 72 days. We have initiated a follow-up campaign to measure these time delays with Gemini North. Finally, we present initial results from an X-ray monitoring program with Swift , indicating the presence of hard X-ray emission from the lensed quasar, as well as extended X-ray emission from the cluster itself, which is consistent with the lensing mass measurement and the cluster velocity dispersion.},
doi = {10.3847/1538-4357/835/1/5},
journal = {Astrophysical Journal},
number = 1,
volume = 835,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2017},
month = {Fri Jan 20 00:00:00 EST 2017}
}
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