# The splashback boundary of haloes in hydrodynamic simulations

@article{ONeil2020TheSB,
title={The splashback boundary of haloes in hydrodynamic simulations},
author={Stephanie O'Neil and David J Barnes and Mark Vogelsberger and Benedikt Diemer},
journal={arXiv: Astrophysics of Galaxies},
year={2020}
}
The splashback radius, $R_{\rm sp}$, is a physically motivated halo boundary that separates infalling and collapsed matter of haloes. We study $R_{\rm sp}$ in the hydrodynamic and dark matter only IllustrisTNG simulations. The most commonly adopted signature of $R_{\rm sp}$ is the radius at which the radial density profiles are steepest. Therefore, we explicitly optimise our density profile fit to the profile slope and find that this leads to a $\sim5\%$ larger radius compared to other… Expand
3 Citations

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