Index: trunk/MagicSoft/Mars/mmuon/MHSingleMuon.cc
===================================================================
--- trunk/MagicSoft/Mars/mmuon/MHSingleMuon.cc	(revision 7366)
+++ trunk/MagicSoft/Mars/mmuon/MHSingleMuon.cc	(revision 7367)
@@ -240,7 +240,7 @@
 
     //    Double_t err;
-    Double_t mean, meanerr, dummy;
+    Double_t sig, mean, dummy;
+    gMinuit->GetParameter(1, mean, dummy);  // get the mean  value
     gMinuit->GetParameter(2, sig,  dummy);  // get the sigma value
-    gMinuit->GetParameter(1, mean, dummy);  // get the sigma value
 
     for (Int_t i=0; i<entries; i++)
Index: trunk/MagicSoft/Mars/mmuon/MHSingleMuon.h
===================================================================
--- trunk/MagicSoft/Mars/mmuon/MHSingleMuon.h	(revision 7366)
+++ trunk/MagicSoft/Mars/mmuon/MHSingleMuon.h	(revision 7367)
@@ -24,6 +24,6 @@
     Double_t fMargin;               //!
 
-    TProfile fHistPhi;   // Histogram of photon distribution along the arc.
-    TProfile fHistWidth; // Histogram of radial photon distribution of the arc.
+    TProfile fHistPhi;    // Histogram of photon distribution along the arc.
+    TProfile fHistWidth;  // Histogram of radial photon distribution of the arc.
     TH1F     fHistTime;   // Histogram of arrival time distribution along the arc.
 
@@ -50,4 +50,2 @@
 
 #endif
-
-
Index: trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.cc
===================================================================
--- trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.cc	(revision 7366)
+++ trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.cc	(revision 7367)
@@ -38,10 +38,14 @@
 // infomation stored in
 //
-// MMuonCalibPar.
+//   MMuonCalibPar.
 //
 // The information will be available by using the task of
 //
-// MMuonCalibParCalc.
-//
+//   MMuonCalibParCalc.
+//
+// Version 2:
+// ----------
+//   + Float_t fTime;      // Mean arrival time of core pixels
+//   + Float_t fTimeRms;   // Rms of arrival time of core pixels
 //
 //  Input Containers:
@@ -90,4 +94,5 @@
     fCenterY   =  0;
     fTime      =  0;
+    fTimeRms   = -1;
 }
 
@@ -144,4 +149,5 @@
 {
     // ------- Make a temporaray copy of the signal ---------
+    // ------- and calculate arrival time parameters --------
     const Int_t n = geom.GetNumPixels();
 
@@ -153,5 +159,6 @@
     Int_t q=0;
 
-    Float_t fTime2=0;
+    Float_t mean=0;
+    Float_t sq  =0;
 
     for (int i=0; i<n; i++)
@@ -168,15 +175,18 @@
 
             //timing
-            if(pix.IsPixelCore())
-            {
-                fTime  += pix.GetArrivalTime();
-                fTime2 += pix.GetArrivalTime()*pix.GetArrivalTime();
-                q++;
-            }
+            if (!pix.IsPixelCore())
+                continue;
+
+            mean += pix.GetArrivalTime();
+            sq   += pix.GetArrivalTime()*pix.GetArrivalTime();
+            q++;
         }
     }
-    fTime    = fTime/q;
-    fTime2   = fTime2/q;
-    fTimeRms = TMath::Sqrt(fTime2-(fTime*fTime));
+
+    mean /= q;
+    sq   /= q;
+
+    fTime    = mean;
+    fTimeRms = TMath::Sqrt(sq-mean*mean);
 
     fSignal.Set(p);
Index: trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.h
===================================================================
--- trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.h	(revision 7366)
+++ trunk/MagicSoft/Mars/mmuon/MMuonSearchPar.h	(revision 7367)
@@ -21,6 +21,6 @@
     Float_t fCenterX;   // An estimated center position in X of the muon ring [mm]
     Float_t fCenterY;   // An estimated center position in Y of the muon ring [mm]
-    Float_t fTime;
-    Float_t fTimeRms;
+    Float_t fTime;      // Mean arrival time of core pixels
+    Float_t fTimeRms;   // Rms of arrival time of core pixels
 
     MArrayF fSignal;    //! Temporary storage for signal
@@ -57,5 +57,5 @@
     void   Print(const MGeomCam &geom, Option_t *opt=NULL) const;
 
-    ClassDef(MMuonSearchPar, 1) // Container to hold muon search parameters
+    ClassDef(MMuonSearchPar, 2) // Container to hold muon search parameters
 };