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arXiv · 2109.09439

Catalogues of voids as antihalos in the local Universe

Harry Desmond·Maxwell L. Hutt·Julien Devriendt·Adrianne Slyz
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Abstract

A recently-proposed algorithm identifies voids in simulations as the regions associated with halos when the initial overdensity field is negated. We apply this method to the real Universe by running a suite of constrained simulations of the 2M++ volume with initial conditions inferred by the BORG algorithm, along with the corresponding inverted set. Our 101 inverted and uninverted simulations, spanning the BORG posterior, each identify ~150,000 "voids as antihalos" with mass exceeding $4.38\times10^{11} \: \mathrm{M_\odot}$ (100 particles) at $z=0$ in a full-sky sphere of radius 155 Mpc/h around the Milky Way. We calculate the size function, volume filling fraction, ellipticity, central density, specific angular momentum, clustering and stacked density profile of the voids, and cross-correlate them with those produced by VIDE on the same simulations. We make our antihalo and VIDE catalogues publicly available.

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Harry Desmond, Maxwell L. Hutt, Julien Devriendt, Adrianne Slyz. 2021-09-20. Catalogues of voids as antihalos in the local Universe. https://doi.org/10.1093/mnrasl%2Fslac008

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