GSI Forum
GSI Helmholtzzentrum für Schwerionenforschung

Home » PANDA » PandaRoot » Tracking » WirepointHitPolicy detplane implementation
Re: WirepointHitPolicy detplane implementation [message #8132 is a reply to message #8129] Mon, 23 March 2009 13:32 Go to previous messageGo to previous message
Anonymous Poster From: *e18.physik.tu-muenchen.de
Hi Ola & Lia,

on second thought, I think it is necessary to have two hit policies for detectors which can measure a position along the wire and those which can not. The reason is the dimensionality of the hit. The DCH hit is only a 1-D information. There for the correct HMatrix (OK, this has nothing to do with the policy) would be 5x1 and would be [0,0,0,1,0] assuming that the U-vector points perpendicular to the wire, like it does.

Also in the policy, where you also fix the dimensionality when you calculate the hit coordinates and covariances this should be dont correctly.

It is true that just putting the coordinate to zero with a huge errors will lead to an unbiased fit, but the number of degrees of freedom for the chi2 calculation will be wrong.

If you dont have any objections I will introduce a new policy WireHitPolicy (without the point) which will do this correctly. I would then still ask you to check the detPlane() method for your choice of detector plane before you use it.

Does that make sense? Would you have some time to test this new implementation?

Cheers, Christian
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: Urgent fixes in FairGeanePro.cxx needed
Next Topic: genfit LGPL
Goto Forum:
  


Current Time: Wed Apr 24 23:20:43 CEST 2024

Total time taken to generate the page: 0.01003 seconds