Galactic star formation enhanced and quenched by ram pressure in groups and clusters

摘要: We investigate how ram pressure of intragroup and intracluster medium can influence the spatial temporal variations star formation (SF) disk galaxies with halo masses (M_h) ranging from 10^10 M_sun to 10^12 (i.e., dwarf irregular Milky Way-type) in groups clusters 10^13 < M_h/M_sun 10^15 by using numerical simulations a new model for time-varying pressure. The long-term evolution SF rates H_alpha morphologies corresponding distributions star-forming regions are particularly investigated different parameters. principal results as follows. Whether enhance or reduce depends on M_h inclination angles gas disks respect their orbital directions given orbit environment. For example, be moderately enhanced M_h=10^12 at pericenter passages cluster M_h=10^14 whereas it completely shut down (`quenching') low-mass M_h=10^10 M_sun. Ram H_alpha-to-optical-disk-size ratios revel reduction orbits Disk under strong show characteristic such ring-like, one-sided, crescent-like distributions.