A Dynamical Study of an HST+Chandra Sample of Strong Lensing Clusters
PI:
Matthew Bayliss
Co-I(s):
Raven Gassis, Prasanna Adhikari, Keren Sharon, Michael Gladders, Hakon Dahle, Gourav Khullar, Riley Owens, Keunho Kim, Guillaume Mahler
Abstract
We propose for the next in a planned sequence of programs that will measure spectroscopic redshifts for >=50 cluster member galaxies in each of 32 strong lensing selected galaxy clusters to measure robust dynamical caustic masses out to the virial radii of all clusters. This program builds on archival Hubble and Chandra observations, as well as archival Gemini/GMOS spectroscopy used to measure redshifts of faint lensed sources. From the available HST and Chandra data there are published strong lensing models and hot intra-cluster medium constraints available for the entire sample. This proposal aims to fill in the missing piece: dynamical total/virial mass estimates for each cluster. The dynamical data can be efficiently obtained using Gemini/GMOS to perform multi-object spectroscopy of the lensing clusters, targeting member galaxies down to m*+1.5 to obtain N>=50 member redshifts in each cluster. The proposed dynamical data would allow us to reconstruct the detailed shape of the mass distribution over three decades in radius and test for biases in common mass observable scaling relations (e.g., X-ray vs dynamics) for the strong lensing cluster sample. This project will be the core of one PhD thesis and one undergraduate thesis for students in the PI's research group.