Upper panels: relative change of the specific AM with respect to the initial value, Δl_int/l_int = (l_int(t) − l_int(t = 0))/l_int(t = 0), of old stars of a gSb galaxy as a function of initial radius r_ini (scaled by R_d) during a minor merger with a dSb galaxy on a direct orbit (gSbdSb01dir33). Also shown is the average of Δl_int/l_int as a function of r_ini/R_d in each epoch (overlaid solid line). The vertical bar on the left shows the color scale indicating the number of old stars at certain Δl_int/l_int values. Lower panels: the distribution of Δl_int/l_int of old stars of an isolated galaxy with the same initial structure as the primary galaxy in the minor merger case.