2022-8-3

Applications of Hydrodynamical Simulations for Clustering of Emission Line Galaxies

speaker: Ken Osato

Abstract:
In order to address the structure formation and evolution at the distant Universe, emission line galaxies (ELGs) are suitable targets for upcoming spectroscopic surveys (PFS, Euclid, DESI). Since the strong emission line is sourced by massive OB-type stars, in general, ELGs are star-forming young galaxies. Thus, the clustering nature of ELGs is expected to be quite different from that of luminous red galaxies, which are widely studied in the past spectroscopic observations. In order to address clustering properties of ELGs, we utilise galaxy formation hydrodynamical simulations: IllustrisTNG. We have developed the method to simulate emission line intensity with stellar population synthesis code PEGASE-3. In simulations, we can directly investigate the relation between properties of ELGs and host halos and measure the cosmological statistics, e.g., correlation function. First, we measure the halo occupation distribution (HOD) and find the signature of infalling distinct halo contribution as suggested by semi-analytic simulations. Next, we meaure the projected correlation function and infer HOD parameters with the correlation function. Finally, we discuss whether the true HOD can be reproduced from the projected correlation function measurement.