Observational Measures of Halo Properties Beyond Mass

Peter Behroozi

Department of Astronomy and Steward Observatory, University of Arizona

Abstract: Different properties of dark matter haloes, including growth rate, concentration, interaction history, and spin, correlate with environment in unique, scale-dependent ways.  While these halo properties are not directly observable, galaxies will inherit their host haloes’ correlations with environment.  As a result, measures of environment have the potential to reveal how galaxy properties are correlated with halo properties beyond halo mass.  We show preliminary results that different halo properties imprint distinct scale-dependent signatures in both the two-point correlation function and the distribution of distances to kth nearest neighbors.  We show that these signatures are strong, and are accessible even with low-resolution (e.g., grism) spectroscopy at higher redshifts.  Comparing observed two-point correlation functions for large and small galaxies at z=0, we use these results to show that classic galaxy size models (i.e., galaxy size being proportional to halo spin) cannot be correct.  Instead, we find that models where galaxy size depends inversely on concentration are a better match to observations.

یکشنبه 30 شهریور 1399، ساعت 19:00

Sunday 20 September 2020 – 19:00 Tehran Time

اتاق سمینار مجازی –Virtual Seminar Room

https://vc.sharif.edu/ch/cosmology

گزینه ورود به صورت مهمان – Enter as a Guest