The AC detectors are the A in our AL, AR, and ALAR rates. Eight rectangular detectors, made at UMD, forming an anti-coincidence cylinder around the stack of D1 through D5. AL and AR presumably correspond to Anti-coincidence Left and Right. Left and right compared to what, I don't know. The output of four of the detectors are summed in AL and the other four in AR. ALAR is the coincidence rate of the two. As you will remember AL and AR in both V1 and V2 became very noisy during the Jupiter encounter. They all gradually quieted down over time until AR on V1 is the only remaining noisy one, ~4000 c/s with D2 off. ALAR on V2 also disappeared around the Jupiter encounter. Maybe a lost register or something. Apparently the high AR rate has an effect on the Ch31 rate, and Rob has come up with some method of correcting it sector by sector, but it is apparently a painful process. SMK would like to quiet down AR so corrections wouldn't be necessary. The 8 detectors are connected in parallel pairs, AI, AII, AIII, AIV. Those pairs can be turned off individually. Unfortunately, no one remembers which two pairs comprise AR. I think it might be a mistake to turn any off since it could change the detected anisotropy in an unknown way, and that's what we're mainly interested in. I'm surprised that 4000 c/s is high enough to require a correction, but maybe it is.