Ludovic Van Waerbeke, Jonathan Benjamin, Thomas Erben, Catherine Heymans, Hendrik Hildebrandt, Henk Hoekstra, Thomas D. Kitching, Yannick Mellier, Lance Miller, Jean Coupon, Joachim Harnois-Déraps, Liping Fu, Michael J. Hudson, Martin Kilbinger, Konrad Kuijken, Barnaby T. P. Rowe, Tim Schrabback, Elisabetta Semboloni, Sanaz Vafaei, Edo van Uitert, Malin Velander
We present a quantitative analysis of the largest contiguous maps of projected mass density obtained from gravitational lensing shear. We use data from the 154 deg2 covered by the Canada France Hawaii Telescope Lensing Survey. Our study is the first attempt to quantitatively characterize the scientific value of lensing maps, which could serve in the future as a complementary approach to the study of the dark universe with gravitational lensing. We show that mass maps contain unique cosmological information beyond that of traditional two-points statistical analysis techniques. Using a series of numerical simulations, we first show that gravitational lensing inversion provides a reliable probe of the projected matter distribution of large scale structure. We validate our analysis by quantifying the robustness of the maps with various statistical estimators. The same process is then applied to the CFHTLenS data. It is found that the statistical properties of the projected mass are fully consistent with the cosmological analysis performed on the shear signal discussed in CFHTLenS companion papers. The maps also lead to a significant measurement of the third order moment of the projected mass in agreement with analytic predictions, and to a marginal detection of the fourth order moment. Tests for residual systematics are found to be consistent with zero for the statistical estimators we used. A new approach for the comparison of the reconstructed mass map to that predicted from the galaxy distribution reveals the existence of giant voids in the dark matter maps as large as 3 degrees on the sky. Our analysis shows that lensing mass maps not only is consistent with the results obtained by the traditional shear approach, but also enable new analysis techniques such as peak statistics and the morphological analysis of the projected dark matter distribution.
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http://arxiv.org/abs/1303.1806
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