Revealing the role of environmental and mass quenching with SAG

CORA, SOFÍA A; HOUGH , TOMAS; VEGA-MARTÍNEZ, CRISTIAN A; ORSI, ÁLVARO A

Santiago de Chile

Congreso; Segunda Reunión Binacional AAA-SOCHIAS; 2018

AAA-SOCHIAS

We study the relevance of mass and environmental quenching on the star formation (SF) history of z = 0 passive satellite galaxies by analysing a galaxy catalogue generated from the combination of the semianalytic model of galaxy formation sag and the MultiDark simulation mdpl2. We find M ≈ 10^10.5 Msun to be the stellar mass scale where mass quenching becomes important. Environmental processes dominate the SF quenching of low-mass satellite galaxies (M = 10^10.1 Msun). High-mass galaxies are more likely to quench as centrals, and those that remain active after first infall are mainly affected by mass quenching. The whole quenching process iswell described by a delay-then-fade quenching scenario. During the first phase of this two-stage process, the star formation rate of satellites declines as they were centrals in a delay time that ranges from ≈ 3 Gyr to ≈ 1 Gyr for low-mass (M ≈ 10^10 Msun) and high-mass (M ≈ 10^11 Msun) satellites, respectively. During the second stage, the gas cooling rate and, consequently, the star formation rate decay more abruptly until the satellite becomes passive. The time span of this fading phase is ≈ 1 Gyr, largely independent of stellar mass.