# Stellar-to-halo mass relation of cluster galaxies

## TL;DR

This study investigates how the dark matter halos of satellite galaxies are stripped by tidal forces within clusters, using weak lensing data to compare the stellar-to-halo mass relation at different cluster-centric distances.

## Contribution

It provides empirical evidence of tidal stripping effects on dark matter halos of satellite galaxies by analyzing their stellar-to-halo mass relation across cluster environments.

## Key findings

- Halo mass for satellites decreases towards the cluster center.
- Stellar-to-halo mass relation aligns with theoretical models in outskirts.
- Significant halo mass reduction observed in cluster cores.

## Abstract

In the hierarchical formation model, galaxy clusters grow by accretion of smaller groups or isolated galaxies. During the infall into the centre of a cluster, the properties of accreted galaxies change. In particular, both observations and numerical simulations suggest that its dark matter halo is stripped by the tidal forces of the host. We use galaxy-galaxy weak lensing to measure the average mass of dark matter haloes of satellite galaxies as a function of projected distance to the centre of the host, for different stellar mass bins. Assuming that the stellar component of the galaxy is less disrupted by tidal stripping, stellar mass can be used as a proxy of the infall mass. We study the stellar to halo mass relation of satellites as a function of the cluster-centric distance to measure tidal stripping. We use the shear catalogues of the DES science verification archive, the CFHTLenS and the CFHT Stripe 82 (CS82) surveys, and we select satellites from the redMaPPer catalogue of clusters. For galaxies located in the outskirts of clusters, we find a stellar to halo mass relation in good agreement with the theoretical expectations from \citet{moster2013} for central galaxies. In the centre of the cluster, we find that this relation is shifted to smaller halo mass for a given stellar mass. We interpret this finding as further evidence for tidal stripping of dark matter haloes in high density environments.