What process strips a galaxy's cool interstellar gas within the ICM?

Ram-pressure stripping

Ram-pressure stripping is a highly effective mechanism for altering galaxy evolution within dense cluster environments. As a galaxy travels at high speeds, potentially thousands of kilometers per second, through the dense, superheated plasma that constitutes the intracluster medium (ICM), the kinetic pressure exerted by this hot gas acts like a strong cosmic wind. This pressure physically pushes and strips away the galaxy's cooler, lower-density interstellar medium, which is the fuel reservoir necessary for ongoing star formation. The removal of this gas leads directly to the galaxy quickly ceasing star production, a process known as quenching, and often results in the galaxy transforming its morphology, frequently from a spiral type into an elliptical type.