Ram Pressure Stripping in High-Density Environments
  Galaxies living in rich environments are suffering different perturbations
able to drastically affect their evolution. Among these, ram pressure
stripping, i.e. the pressure exerted by the hot and dense intracluster medium
(ICM) on galaxies moving at high velocity within the cluster gravitational
potential well, is a key process able to remove their interstellar medium (ISM)
and quench their activity of star formation. This review is aimed at describing
this physical mechanism in different environments, from rich clusters of
galaxies to loose and compact groups. We summarise the effects of this
perturbing process on the baryonic components of galaxies, from the different
gas phases (cold atomic and molecular, ionised, hot) to magnetic fields and
cosmic rays, and describe their induced effects on the different stellar
populations, with a particular attention to its role in the quenching episode
generally observed in high density environments. We also discuss on the
possible fate of the stripped material once removed from the perturbed galaxies
and mixed with the ICM, and we try to estimate its contribution to the
pollution of the surrounding environment. Finally, combining the results of
local and high redshift observations with the prediction of tuned models and
simulations, we try to quantify the importance of this process on the evolution
of galaxies of different mass, from dwarfs to giants, in various environments
and at different epochs.
