Allen Pinjic
Pronouns: he/him
Research Mentor(s): Marcelle Soares-Santos
Research Mentor School/College/Department: Physics / LSA
Program: UROP
Session: Session 5 (2:40pm – 3:30pm)
Authors: Marcelle Soares-Santos, Allen Pinjic, Johnny Esteves
Abstract
How can you weigh a dark matter halo with Galaxy Cluster optical images? This question describes the core challenge of our project. In this study, our goal is to infer the scaling relation between the visible and the invisible, through the measurements of galaxies’ stellar mass, mu-star, and the halo mass, Mvir. For this purpose, we use a third party, the Sunyaev-Zeldovich (SZ) signal, to calibrate our measurements. Since the distortions in the CMB signal, called the SZ effect and which are caused by the galaxy cluster environment, have a tight relationship with the halo mass they are a powerful multi-wavelength probe to constrain the information of optical clusters. In this study, we use the South-Pole Telescope (SPT), SPT-SZ, SPTpol-ECS, and SPTpol-100d cluster samples and the Dark Energy Survey (DES) photometric data. Specifically, using DES photometry we measure mu-star, the total cluster galaxy’s stellar mass. Applying a statistical Bayesian treatment with multiple observables (mu-star and SZ-signal) we infer the stellar-to-halo mass relation of our optical proxy, mu-star, and the dark matter, halo mass. For this purpose, we implemented an MCMC script within a NERSC high-performance-based computing environment from which we derived our results. We’re currently validating our methodology and we expect to establish an optimal mu-star definition for cosmological analysis. In the future, the results of this work will be used to measure the dark matter fraction of the Universe and other constraining cosmological parameters.
