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arXiv · astro-ph/0507360

Discovery of Multiply Imaged Galaxies behind the Cluster and Lensed Quasar SDSS J1004+4112

Keren Sharon·Eran O. Ofek·Graham P. Smith·Tom J. Broadhurst·Dan Maoz·Christopher S. Kochanek·Masamune Oguri·Yasushi Suto·Naohisa Inada·Emilio E. Falco
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Abstract

We have identified three multiply imaged galaxies in Hubble Space Telescope images of the redshift z=0.68 cluster responsible for the large-separation quadruply lensed quasar, SDSS J1004+4112. Spectroscopic redshifts have been secured for two of these systems using the Keck I 10m telescope. The most distant lensed galaxy, at z=3.332, forms at least four images, and an Einstein ring encompassing 3.1 times more area than the Einstein ring of the lensed QSO images at z=1.74, due to the greater source distance. For a second multiply imaged galaxy, we identify Ly_alpha emission at a redshift of z=2.74. The cluster mass profile can be constrained from near the center of the brightest cluster galaxy, where we observe both a radial arc and the fifth image of the lensed quasar, to the Einstein radius of the highest redshift galaxy, ~110 kpc. Our preliminary modeling indicates that the mass approximates an elliptical body, with an average projected logarithmic gradient of ~-0.5. The system is potentially useful for a direct measurement of world models in a previously untested redshift range.

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Keren Sharon, Eran O. Ofek, Graham P. Smith, Tom J. Broadhurst, Dan Maoz, Christopher S. Kochanek, Masamune Oguri, Yasushi Suto, Naohisa Inada, Emilio E. Falco. 2005-07-14. Discovery of Multiply Imaged Galaxies behind the Cluster and Lensed Quasar SDSS J1004+4112. https://doi.org/10.1086/452633

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