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arXiv · 2403.02111

The radial orbits of ram-pressure-stripped galaxies in clusters from the GASP survey

A. Biviano·B. M. Poggianti·Y. Jaffé·A. C. C. Lourenço·L. Pizzuti·A. Moretti·B. Vulcani
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Abstract

We analyse a sample of 244 ram-pressure-stripped candidate galaxy members within the virial radius of 62 nearby clusters, to determine their velocity anisotropy profile $β(r)$. We use previously determined mass profiles for the 62 clusters to build an ensemble cluster by stacking the 62 cluster samples in projected phase-space. We solve the Jeans equation for dynamical equilibrium by two methods, MAMPOSSt and the Jeans inversion technique, and determine $β(r)$ both in parametric form and non-parametrically. The two methods consistently indicate that the orbits of the ram-pressure-stripped candidates are increasingly radial with distance from the cluster center, from almost isotropic ($β\simeq 0$) at the center, to very radial at the virial radius ($β\simeq 0.7$). The orbits of cluster galaxies undergoing ram-pressure stripping are similar to those of spiral cluster galaxies, but more radially elongated at large radii.

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A. Biviano, B. M. Poggianti, Y. Jaffé, A. C. C. Lourenço, L. Pizzuti, A. Moretti, B. Vulcani. 2024-03-04. The radial orbits of ram-pressure-stripped galaxies in clusters from the GASP survey. https://arxiv.org/abs/2403.02111

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