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arXiv · 1701.04412

A test for skewed distributions of dark matter and a possible detection in galaxy cluster Abell 3827

Peter Taylor·Richard Massey·Mathilde Jauzac·Frédéric Courbin·David Harvey·Rémy Joseph·Andrew Robertson
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Abstract

Simulations of self-interacting dark matter (SIDM) predict that dark matter should lag behind galaxies during a collision. If the interaction is mediated by a high-mass force carrier, the distribution of dark matter can also develop asymmetric dark matter tails. To search for this asymmetry, we compute the gravitational lensing properties of a mass distribution with a free {\em skewness} parameter. We apply this to the dark matter around the four central galaxies in cluster Abell~3827. In the galaxy whose dark matter peak has previously been found to be offset, we tentatively measure a skewness $s=0.23^{+0.05}_{-0.22}$ in the same direction as the peak offset. Our method may be useful in future gravitational lensing analyses of colliding galaxy clusters and merging galaxies.

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Peter Taylor, Richard Massey, Mathilde Jauzac, Frédéric Courbin, David Harvey, Rémy Joseph, Andrew Robertson. 2017-01-16. A test for skewed distributions of dark matter and a possible detection in galaxy cluster Abell 3827. https://doi.org/10.1093/mnras/stx855

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