Physical Correlations of the Scatter between Galaxy Mass, Stellar Content, and Halo Mass
| Autor: | Song Huang, Alexie Leauthaud, Andrew Hearin, Peter Behroozi, Christopher Bradshaw |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physics
Cosmology and Nongalactic Astrophysics (astro-ph.CO) Stellar mass 010308 nuclear & particles physics FOS: Physical sciences Astronomy and Astrophysics Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics - Astrophysics of Galaxies 01 natural sciences Accretion (astrophysics) Redshift Cosmology Galaxy Dark matter halo Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) 0103 physical sciences Cluster (physics) Astrophysics::Solar and Stellar Astrophysics Halo 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics Astrophysics - Cosmology and Nongalactic Astrophysics |
| DOI: | 10.48550/arxiv.1905.09353 |
| Popis: | We use the UniverseMachine to analyze the source of scatter between the central galaxy mass, the total stellar mass in the halo, and the dark matter halo mass. We also propose a new halo mass estimator, the cen+N mass: the sum of the stellar mass of the central and the N most massive satellites. We show that, when real space positions are perfectly known, the cen+N mass has scatter competitive with that of richness-based estimators. However, in redshift space, the cen+N mass suffers less from projection effects in the UniverseMachine model. The cen+N mass is therefore a viable low scatter halo mass estimator, and should be considered an important tool to constrain cosmology with upcoming spectroscopic data from DESI. We analyze the scatter in stellar mass at fixed halo mass and show that the total stellar mass in a halo is uncorrelated with secondary halo properties, but that the central stellar mass is a function of both halo mass and halo age. This is because central galaxies in older halos have had more time to grow via accretion. If the UniverseMachine model is correct, accurate galaxy-halo modeling of mass selected samples therefore needs to consider halo age in addition to mass. Comment: 13 pages, 11 figures, submitted to MNRAS |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|