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arXiv · 1108.4929

Cluster-Cluster Lensing and the Case of Abell 383

Adi Zitrin·Yoel Rephaeli·Sharon Sadeh·Elinor Medezinski·Keiichi Umetsu·Jack Sayers·Mario Nonino·Andrea Morandi·Alberto Molino·Nicole Czakon·Sunil R. Golwala
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Abstract

Extensive surveys of galaxy clusters motivate us to assess the likelihood of cluster-cluster lensing (CCL), namely, gravitational-lensing of a background cluster by a foreground cluster. We briefly describe the characteristics of CCLs in optical, X-ray and SZ measurements, and calculate their predicted numbers for $Λ$CDM parameters and a viable range of cluster mass functions and their uncertainties. The predicted number of CCLs in the strong-lensing regime varies from several ($<10$) to as high as a few dozen, depending mainly on whether lensing triaxiality bias is accounted for, through the c-M relation. A much larger number is predicted when taking into account also CCL in the weak-lensing regime. In addition to few previously suggested CCLs, we report a detection of a possible CCL in A383, where background candidate high-$z$ structures are magnified, as seen in deep Subaru observations.

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Adi Zitrin, Yoel Rephaeli, Sharon Sadeh, Elinor Medezinski, Keiichi Umetsu, Jack Sayers, Mario Nonino, Andrea Morandi, Alberto Molino, Nicole Czakon, Sunil R. Golwala. 2011-08-24. Cluster-Cluster Lensing and the Case of Abell 383. https://doi.org/10.1111/j.1365-2966.2011.20155.x

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