  Reproducing the observed quenched fraction of satellite galaxies has been a
long-standing issue for galaxy formation models. We modify the treatment of
environmental effects in our state-of-the-art GAlaxy Evolution and Assembly
(GAEA) semi-analytic model to improve our modelling of satellite galaxies.
Specifically, we implement gradual stripping of hot gas, ram-pressure stripping
of cold gas, and an updated algorithm to account for angular momentum exchanges
between the gaseous and stellar disc components of model galaxies. Our updated
model is in good agreement with the observed quenched fractions for central and
satellite galaxies, and their dependencies on stellar mass and halo mass. We
also find consistency between model predictions and observational estimates of
quenching time for satellite galaxies; HI, H$_2$ fractions of central galaxies;
and deficiencies of HI, H$_2$, SFR of galaxies in cluster haloes. Analysing
results from our updated model, we find that the dominant quenching mechanisms
are hot-gas stripping for low-mass galaxies, and AGN feedback for massive
galaxies. The Ram-pressure stripping of cold gas has a limited impact on the
predicted quenched fractions, nonetheless, is needed to reproduce the observed
HI deficiencies.
