The problem is the following: I start with 39Ar atoms and let them decay by using the G4RadioactiveDecay class. For 39Ar this is not a problem, but for more complicate things like 222Rn and daughters, the processing speed drops down by more than a factor 1000. I wonder where this unacceptable loss of speed comes from. It should be possible to make the radioactive decay almost as fast as the other physical processes. In fact I cannot use the G4RadioactiveDecay, because it is impossible to get enough statistics. Of course it never can be excluded that I made a mistake in writing my code, but a colleague of mine here at MPIK has observed the same effect independently, and I have heard of other cases as well, so it seems to be a general problem.
Hi Fan, was this already chreaed out in 7.0? Many greetings, Hans-Peter.
In version ealier than 7.0, one needs should use the fast beta decay mode if speed is a concern. This is controlled by the command "/grdm/fBeta true". Since 7.0 a new faster beta decay algorithm is used and there is no more accurate/fast modes.
