11:00–11:30 am ERC 401
Constraining Dark Matter Halo Truncation In Cluster Galaxies After Infall Through Strong Lensing Perturbations
Advisor: Mike Gladders
The infall of galaxies into clusters is thought to be characterized by intense dynamical interactions between the galaxy and cluster halos. Cosmological simulations predict that tidal friction causes the dark matter halos around infalling galaxies to become truncated. In this study we examine six foreground early type galaxies located inside clusters acting as strong gravitational lenses at a redshift range of 0.4 < z < 0.61. Galaxies were chosen based on their proximity to resolved, multiply-image lensed sources. The mass content associated with each sample member was decomposed into the stellar and dark components using a combination of strong lens analysis and spectral energy density fitting. The dark matter fraction within 5 effective radii was then calculated for each sample member and compared to a sample of field galaxies obtained from Harris et al. (2020). It was found that the cluster sample was systematically lower in stellar mass than the field sample, limiting the ability to compare between samples. The mean dark matter fraction for the cluster sample was found to be 0.65, lower than the mean value for field galaxies at 0.791, however due to sample size this was not found to be statistically significant. The most massive members of the cluster sample were isolated and their mean dark matter fraction was calculated at .403, which was found to be significant at p=.0004.