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arXiv · 2006.03506

Shape, Color and Distance in Weak Gravitational Flexion

Joseph M. Fabritius II·Evan J. Arena·David M. Goldberg
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Abstract

Canonically, elliptical galaxies might be expected to have a perfect rotational symmetry, making them ideal targets for flexion studies - however, this assumption hasn't been tested. We have undertaken an analysis of low and high redshift galaxy catalogs of known morphological type with a new gravitational lensing code, Lenser. Using color measurements in the u-r band and fit Sersic index values, objects with characteristics consistent with early-type galaxies are found to have a lower intrinsic scatter in flexion signal than late-type galaxies. We find this measured flexion noise can be reduced by more than a factor of two at both low and high redshift.

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Joseph M. Fabritius II, Evan J. Arena, David M. Goldberg. 2020-06-05. Shape, Color and Distance in Weak Gravitational Flexion. https://doi.org/10.1093/mnras/staa3928

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