GSI Forum
GSI Helmholtzzentrum für Schwerionenforschung

Home » PANDA » PandaRoot » Tracking » covariances in global coordinates
covariances in global coordinates [message #5985] Thu, 28 February 2008 12:23
Sebastian Neubert is currently offline  Sebastian Neubert
Messages: 282
Registered: March 2006
Location: Munich
first-grade participant

From: *

LSLTrackRep now can produce the required 6x6 covariances.

The respective methods are:

virtual TVectorT<double> getGlobal(); // (x,y,z,px,py,pz)
virtual TMatrixT<double> getGlobalCov(); // covariances

When the Kalman Filter has been run, this should produce a valid covariance. See also GenfitTester::test_LSLtoGLOB();

However there is one issue:
Since there is always one free parameter in a track (z in the case of LSLTrackRep) the 6x6 covariance matrix is a bit strange. For example at the moment the z-row/column has only the variance and no COvariances! I do not know how to solve this.
Originally this was the reason why I suggested that we should NOT have a 6-coordinate system.
But maybe there is a solution to this which I do not see at the moment.

At least you can start palying around now. Please give me some feedback on what you get! So far I have not investigated the covs too much!

Cheers! Sebastian.

Sebastian Neubert
Technische Universität München
Department Physik E18
tel: +49-8928912592
Read Message
Previous Topic: riemann track finding
Next Topic: GEANE with new external packages
Goto Forum:

Current Time: Fri Jul 12 13:34:24 CEST 2024

Total time taken to generate the page: 0.00725 seconds