dx = AliMathBase::TruncatedGaus(0.0,chdx,cutChdx);
dy = AliMathBase::TruncatedGaus(0.0,chdy,cutChdy);
dz = AliMathBase::TruncatedGaus(0.0,chdz,cutChdz);
dx = AliMathBase::TruncatedGaus(0.0,chdx,cutChdx);
dy = AliMathBase::TruncatedGaus(0.0,chdy,cutChdy);
dz = AliMathBase::TruncatedGaus(0.0,chdz,cutChdz);