geane propagate((CbmTrackParH *TStart, CbmTrackParP *TEnd, Int_t PDG) [message #6653] |
Fri, 02 May 2008 12:00 |
asanchez
Messages: 350 Registered: March 2006
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first-grade participant |
From: *kph.uni-mainz.de
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Hi to Geane experts,
I have a question concerning the function
Propagate(CbmTrackParH *TStart, CbmTrackParP *TEnd, Int_t PDG)
I would like to calculate the length of a track provided
either by genfit or by lhetrack.
In genfit there is now the possibility to obtain
the Length (from geane)of the track by using
prop = _geane->Propagate(&par,&result,_pdg); //211
double l=_geane->GetLengthAtPCA();
But i see that one should always be able to provide
the pdg of the particle.
If one has already a fitted track, and has still access
to the track hits(first or last hit in the track),
is it possible to propagate to one volume(point, plane) by giving the track parameters and the position information, without giving the pdg code.
Thanks in advance
ALicia.
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Re: geane propagate((CbmTrackParH *TStart, CbmTrackParP *TEnd, Int_t PDG) [message #6655 is a reply to message #6654] |
Fri, 02 May 2008 12:37 |
asanchez
Messages: 350 Registered: March 2006
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first-grade participant |
From: *kph.uni-mainz.de
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Hi again,
i have checked the ertrack.F which is called in
propagate(CbmtrackP, cbmtrackP, pdg) at CbmGeanePro.cxx
and so far i have understood(please let me know if i'm wrong)
the pdg code will be use to obtain
information from the particle which will be used
to do the propagation to a point, plane volume ,etc
let's assume that after the tracking, i have only tracks
and i don't have pdg information any more.
if i don't have the pdg of the particle, means that
geane will not work??.
Is that the case?
Is there any way to use ertrack only providing track parameters
from the fit and the start and end position.?
Thanks
ALicia.
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Re: geane propagate((CbmTrackParH *TStart, CbmTrackParP *TEnd, Int_t PDG) [message #6658 is a reply to message #6655] |
Fri, 02 May 2008 15:10 |
Lia Lavezzi
Messages: 291 Registered: May 2007 Location: Torino
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first-grade participant |
From: *47-151.net24.it
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Hi Alicia,
you need to give the PDG code to GEANE because otherwise GEANE does not know which particle it has to propagate through the detector. The tracking is made just like in the Monte Carlo (geant3) with all the random effects switched off, so GEANE needs to know the PDG code of the particle in order to propagate it with the correct energy loss and so on...
Pay attention to the fact that if you track a particle with the wrong PDG code GEANE results will not be reliable: it will calculate its predictions for the wrong particle.
For the moment I could suggest you to use the MC truth to get the PDG code of the tracks and use it for GEANE.
Ciao,
Lia.
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