Releasing the covariance matrix of intersection point along the track direction

[u/mrichter/AliRoot.git] / STEER / AliTrackFitterKalman.cxx

diff --git a/STEER/AliTrackFitterKalman.cxx b/STEER/AliTrackFitterKalman.cxx
index 5251c96a22153d40653f1324ab85d6a0d1f4c4b1..7d46f9fb77b02ff73c191388cb3ec71f1256a854 100755 (executable)
--- a/STEER/AliTrackFitterKalman.cxx
+++ b/STEER/AliTrackFitterKalman.cxx
@@ -278,6 +278,14 @@ Bool_t AliTrackFitterKalman::GetPCA(const AliTrackPoint &p, AliTrackPoint &i) co
 
   TMatrixD iC(tC,TMatrixD::kMult,tmW);
   iC*=mC;
+  Double_t sig2=1.;  // Releasing the matrix by 1 cm along the track direction 
+  iC(0,0) += vx*vx*sig2;
+  iC(0,1) += vx*sig2; 
+  iC(1,1) += sig2;
+  iC(0,2) += vx*vz*sig2;
+  iC(1,2) += vz*sig2;
+  iC(2,2) += vz*vz*sig2;
+
 
   Float_t cov[6]={
     iC(0,0), iC(0,1), iC(0,2),