S0 appears to be >99% efficient except for L.tr.x<-0.6 Run 7711 has T3 and T4 triggers
cut definitions TCut cGoodVDC = "L.tr.n==1&&abs(L.tr.x)<1."; TCut cGoodAngles = "abs(L.tr.tg_th)<0.1&&abs(L.tr.tg_ph)<0.05"; TCut cTarget = "abs(L.tr.tg_y)<0.1"; TCut cCleanTrk = cGoodVDC&&cGoodAngles&&cTarget;
L.tr.x and .y distributions for all events and for events with L.s0.nlthit==0 (Blue) and L.s0.nrthit==0 (Red)
S0 is a little shorter than focal plane, and cuts negative y also, but is this a useful region of focal plane?
Figure 1
Figure 2