|Re: Geane interface in PandaRoot [message #4545 is a reply to message #4516]
||Mon, 25 June 2007 09:15
Registered: May 2007
thank you for waiting, I hope it will not take long: this week
Alberto, Pablo and myself will work almost full time on this and
I made some progress in the weekend already! I will keep you
up to date when there are news.
Regarding the virtual detector planes there was a long and very
useful discussion among Mohammad, Christian and myself two VRVS
meetings ago (I seem to remember you were not present that day):
anyway, as I understand it, to use virtual plane with the
extrapolate to the point of closest approach everything can be
done in the SC. In fact we extrapolate to a given length (and
this is in the SC, i.e. with errors projected in the plane
orthogonal to the track) and the virtual plane is by definition
orthogonal to the track. So the conclusion to this was that
the first interpretation (change from SC to SD) as written in
your note is perhaps not necessary. I have to try it to become
sure about this, but I think it might be correct: to be safe
we have also recoded in double precision the Tr.... routines
in case we need them one day.
Concerning the precision issue, I agree with Christian: this
might be a problem, but this depends on the material budget and
it is difficult to predict it now. I am in touch with some
people in CMS that are studying this effect with the native
GEANE and they will let me know if there are problems.
But we can pospone this if it will become an issue...
Talk to you soon...