A (D. P.): The efficiency is going down probably because the single rate is too high so that this is generating dead time. I remember that the Babar RPC's work in streamer and not in avalanche mode and so the dead area involved is bigger. The real question is why the single rate is high even when no beam is present. More studies should be done to understand this.

A (D. P.): The gas change of the new RPC system is still about 2 volumes per day.