Tracking with different particle hypothesis [message #11561] |
Tue, 08 March 2011 17:10 |
StefanoSpataro
Messages: 2736 Registered: June 2005 Location: Torino
|
first-grade participant |
From: *to.infn.it
|
|
Dear all,
I have done a test trying to check tracking performances for different particle hypothesis.
I run 10k events for each particle kind, e mu pi k p, box generator from 0.15 to 3 GeV/c with lhe+kalman.
The following plot show deltap/p versus p for different particle species. The first row is using the default muon hypothesis in the kalman, the second row is using the correct particle hypothesis:
- Muons: nothing to declare
- Pions: no big differences as we suspect
- Kaons: muon hyp introduces systematics for p < 500 MeV/c, which is fixed using the correct hyp
- Protons: even here the systematic is clear, even at a bit larger momenta. The correct particle hyp seems to fix it, but there is still some noise at very low momenta
- Electrons: the electron hypothesis makes things worse, here at present we have to use muon hyp to have a better momentum resolution
After these plots, maybe we could start to think about running only muon hypothesis for p>1 GeV/c, and muon+kaon+proton hypothesis for p<1 GeV/c, to improve the performances.
This plot is only to give an idea on what is happening, of course dedicated studies are needed, theta and chi2 should be also checked, and probably the electron reconstruction needs an improvement.
|
|
|
|