Adjust TrackParComp ELoss contribution to sigma(q/pt)^2

Author: shahor02

DataFormats/Reconstruction/src/TrackParametrizationWithError.cxx

@@ -1105,7 +1105,7 @@ GPUd() bool TrackParametrizationWithError<value_T>::correctForMaterial(value_t x
   }
 
   // the energy loss correction contribution to cov.matrix: approximate energy loss fluctuation (M.Ivanov)
-  constexpr value_t knst = 0.07f; // To be tuned.
+  constexpr value_t knst = 0.0007f; // To be tuned.
   value_t sigmadE = knst * gpu::CAMath::Sqrt(gpu::CAMath::Abs(dETot)) * e0 / p02 * this->getCharge2Pt();
   cC44 += sigmadE * sigmadE;
 

GPU/GPUTracking/DataCompression/GPUTPCCompressionTrackModel.cxx

@@ -841,7 +841,7 @@ GPUd() void GPUTPCCompressionTrackModel::calculateMaterialCorrection()
 
   // Approximate energy loss fluctuation (M.Ivanov)
 
-  const float knst = 0.07f; // To be tuned.
+  const float knst = 0.0007f; // To be tuned.
   mMaterial.sigmadE2 = knst * mMaterial.EP2 * qpt;
   mMaterial.sigmadE2 = mMaterial.sigmadE2 * mMaterial.sigmadE2;
 

GPU/GPUTracking/Merger/GPUTPCGMPropagator.cxx

@@ -929,7 +929,7 @@ GPUd() void GPUTPCGMPropagator::CalculateMaterialCorrection()
 
   // Approximate energy loss fluctuation (M.Ivanov)
 
-  const float knst = 0.07f; // To be tuned.
+  const float knst = 0.0007f; // To be tuned.
   mMaterial.sigmadE2 = knst * mMaterial.EP2 * qpt;
   mMaterial.sigmadE2 = mMaterial.sigmadE2 * mMaterial.sigmadE2;
 

GPU/GPUTracking/SliceTracker/GPUTPCTrackParam.cxx

@@ -463,7 +463,7 @@ GPUd() void MEM_LG(GPUTPCTrackParam)::CalculateFitParameters(GPUTPCTrackFitParam
 
   // Approximate energy loss fluctuation (M.Ivanov)
 
-  const float knst = 0.07f; // To be tuned.
+  const float knst = 0.0007f; // To be tuned.
   par.sigmadE2 = knst * par.EP2 * qpt;
   par.sigmadE2 = par.sigmadE2 * par.sigmadE2;