Low-mass or dwarf galaxies are particularly compelling laboratories for star formation quenching because they are highly susceptible to quenching effects from both internal stellar feedback and external environment. We explore the role of ram pressure in the environmental regulation of gas content and quenching of low-mass galaxies in zoom-in hydrodynamic simulations of Milky Way (MW) mass hosts. The quiescent fraction of low-mass galaxies increases as their stellar mass decreases and as their distance to a MW-mass host decreases, similar to the Local Group. In addition, the location of a satellite at quenching (in a MW halo, in a low-mass group, or in isolation) and the timing of quenching with respect to different events like infall or pericenter passage depend on the mass of the satellite galaxy. In particular, we find that MW satellites can be efficiently quenched before infall into a MW halo by pre-processing in low-mass groups, where they experience ram pressure comparable to that in a MW halo. Interestingly, the density of halo gas near paired Local Group-like hosts is enhanced at small angles/latitudes off the host galaxy disk versus directly above or below the disk. Preliminary results indicate that both observed and simulated satellites within these low-latitude regions at z=0 may be preferentially quenched, similar to recently reported anisotropic quenching in massive galaxy clusters at low redshift. In addition, we briefly discuss morphological changes to low-mass galaxies induced by the Local Group environment, such as the formation of ultra diffuse galaxies via tidal shocks.
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