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Probing the Cluster Mass Distribution using Subaru Weak Lensing Data

Keiichi Umetsu·Masahiro Takada·Tom Broadhurst
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Abstract

We present results from a weak lensing analysis of the galaxy cluster A1689 (z=0.183) based on deep wide-field imaging data taken with Suprime-Cam on Subaru telescope. A maximum entropy method has been used to reconstruct directly the projected mass distribution of A1689 from combined lensing distortion and magnification measurements of red background galaxies.The resulting mass distribution is clearly concentrated around the cD galaxy, and mass and light in the cluster are similarly distributed in terms of shape and orientation. The azimuthally-averaged mass profile from the two-dimensional reconstruction is in good agreement with the earlier results from the Subaru one-dimensional analysis of the weak lensing data, supporting the assumption of quasi-circular symmetry in the projected mass distribution of the cluster.

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Keiichi Umetsu, Masahiro Takada, Tom Broadhurst. 2007-09-16. Probing the Cluster Mass Distribution using Subaru Weak Lensing Data. https://doi.org/10.1142/s0217732307025340

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