Decrease in sSFR in a simple no-infall, no-recycling case as a function of distance to the center of the halo (gray, right axis; arbitrarily starting at r = 150 kpc) and tidal perturbation parameter P_gc (red to blue, left axis), for a low-mass satellite. The horizontal line shows the threshold value at which the gravitational influence of the halo can trigger inflow within satellite galaxies (Byrd & Valtonen 1990). Both quantities are shown for NFW concentration parameters ranging from c = 1 to c = 40.