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arXiv · 0909.5133

Measuring Dark Matter Substructure with Galaxy-Galaxy Flexion Statistics

D. J. Bacon·A. Amara·J. I. Read
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Abstract

It is of great interest to measure the properties of substructures in dark matter halos at galactic and cluster scales. Here we suggest a method to constrain substructure properties using the variance of weak gravitational flexion in a galaxy-galaxy lensing context. We show the effectiveness of flexion variance in measuring substructures in N-body simulations of dark matter halos, and present the expected galaxy-galaxy lensing signals. We show the insensitivity of the method to the overall galaxy halo mass, and predict the method's signal-to-noise for a space-based all-sky survey, showing that the presence of substructure down to 10^9 M_\odot halos can be reliably detected.

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D. J. Bacon, A. Amara, J. I. Read. 2009-09-28. Measuring Dark Matter Substructure with Galaxy-Galaxy Flexion Statistics. https://doi.org/10.1111/j.1365-2966.2010.17316.x

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