| Re: Geant3 tracking cuts for the EMC [message #9571 is a reply to message #9568] |
Fri, 16 October 2009 17:36   |
Jens Sören Lange
Messages: 193
Registered: June 2005
|
first-grade participant |
From: *physik.uni-giessen.de
|
|
| Bertram Kopf wrote on Fri, 16 October 2009 15:25 |
... range cuts instead of fixed energy cuts (at least for G4). I think that such cuts are more reasonable and more convenient for tuning the parameters with real data in the future.
Cheers,
Bertram.
|
Hi Bertram,
here I have a different opinion.
I think experimentally (for "real data") it is really much easier to set threshold (e.g. discriminator) to energy (e.g. 1 MeV) and not to a particle range (e.g. 1 mm). In fact, so far we were (e.g. for the EMC) always talking about 1 MeV threshold or 3 MeV threshold or whatever value, but never about "threshold of 5 mm for a e-, but 3mm for a pi+ (in the same crystal)".
I also think that "1 mm range cut" gives just one possible result (e.g. for cluster energy), but nobody can say if it gives the correct result or not. Only the comparison to G3 or prototypes (and getting consistent results) can tell us which is the correct result. There was quite some discussion about this when we found the singificant differences between G3 and G4. See e.g.
http://panda-wiki.gsi.de/cgi-bin/view/Computing/Minutes06May2008
http://panda-wiki.gsi.de/cgi-bin/view/Computing/Minutes13May2008
cheers, Soeren
P.S. the equivalent energy threshold values in your table are order of 0.1 eV or even finer, which is most probably too fine for tuning anyway.
|
|
|
|
GSI Forum
Search
Help
Members
Login
Home
