[Common] Fix PID response for Z=2 nuclei (#11795)

fmazzasc · web-flow · commit 327103816ebc · 2025-07-04T10:01:32.000+02:00
diff --git a/Common/DataModel/PIDResponseITS.h b/Common/DataModel/PIDResponseITS.h
@@ -93,7 +93,8 @@ struct ITSResponse {
   template <o2::track::PID::ID id, typename T>
   static float nSigmaITS(const T& track)
   {
-    return nSigmaITS<id>(track.itsClusterSizes(), track.p(), track.eta());
+    unsigned int charge = (id == o2::track::PID::Helium3 || id == o2::track::PID::Alpha) ? 2 : 1;
+    return nSigmaITS<id>(track.itsClusterSizes(), charge * track.p(), track.eta());
   }
 
   static void setParameters(float p0, float p1, float p2,

Original file line number	Diff line number	Diff line change
`@@ -93,7 +93,8 @@ struct ITSResponse {`
`93`	`93`	`template <o2::track::PID::ID id, typename T>`
`94`	`94`	`static float nSigmaITS(const T& track)`
`95`	`95`	`{`
`96`		`- return nSigmaITS<id>(track.itsClusterSizes(), track.p(), track.eta());`
	`96`	`+ unsigned int charge = (id == o2::track::PID::Helium3 \|\| id == o2::track::PID::Alpha) ? 2 : 1;`
	`97`	`+ return nSigmaITS<id>(track.itsClusterSizes(), charge * track.p(), track.eta());`
`97`	`98`	`}`
`98`	`99`
`99`	`100`	`static void setParameters(float p0, float p1, float p2,`