  While dwarf galaxies observed in the field are overwhelmingly star-forming,
dwarf galaxies in environments as dense or denser than the Milky Way are
overwhelmingly quenched. In this paper, we explore quenching in the lower
density environment of the Small-Magellanic-Cloud-mass galaxy NGC 3109
($\text{M}_* \sim 10^8 \, \text{M}_\odot$), which hosts two known dwarf
satellite galaxies (Antlia and Antlia B), both of which are HI deficient
compared to similar galaxies in the field and have recently stopped forming
stars. Using a new semi-analytic model in concert with the measured star
formation histories and gas masses of the two dwarf satellite galaxies, we show
that they could not have been quenched solely by direct ram pressure stripping
of their interstellar media, as is common in denser environments. Instead, we
find that separation of the satellites from pristine gas inflows, coupled with
stellar-feedback-driven outflows from the satellites (jointly referred to as
the starvation quenching model), can quench the satellites on timescales
consistent with their likely infall times into NGC 3109's halo. It is currently
believed that starvation is caused by "weak" ram pressure that prevents
low-density, weakly-bound gas from being accreted onto the dwarf satellite, but
cannot directly remove the denser interstellar medium. This suggests that
star-formation-driven outflows serve two purposes in quenching satellites in
low-mass environments: outflows from the host form a low-density circumgalactic
medium that cannot directly strip the interstellar media from its satellites,
but is sufficient to remove loosely-bound gaseous outflows from the dwarf
satellites driven by their own star formation.
