SPIM Brem Lab Instructions - Revision history

Foretony at 17:49, 17 March 2025

2025-03-17T17:49:30Z

Foretony at 17:16, 17 March 2025

2025-03-17T17:16:12Z

Foretony at 02:27, 17 March 2025

2025-03-17T02:27:59Z

Foretony at 02:24, 17 March 2025

2025-03-17T02:24:43Z

Foretony at 02:23, 17 March 2025

2025-03-17T02:23:57Z

Foretony at 04:09, 10 March 2025

2025-03-10T04:09:45Z

Foretony at 05:09, 5 March 2025

2025-03-05T05:09:47Z

Foretony at 05:06, 5 March 2025

2025-03-05T05:06:44Z

Foretony at 03:59, 5 March 2025

2025-03-05T03:59:37Z

Foretony at 21:24, 30 September 2015

2015-09-30T21:24:39Z

@@ Line 36: / Line 36: @@
                  auto secstep = (*secondary)[i];
                  outfile
-                  << secstep->GetKineticEnergy()  << ", "
+                  << secstep->GetKineticEnergy()  << "  "
-                   << secstep->GetPosition().x()<< ","
+                   << secstep->GetPosition().x()<< "  "
-                   << secstep->GetPosition().y() << ","
+                   << secstep->GetPosition().y() << "  "
-                   << secstep->GetPosition().z() << ","
+                   << secstep->GetPosition().z() << "  "
-                   << secstep->GetMomentum().x() << ", "
+                   << secstep->GetMomentum().x() << "  "
-                   << secstep->GetMomentum().y() << ", "
+                   << secstep->GetMomentum().y() << "  "
                    << secstep->GetMomentum().z()
                    << std::endl;
@@ Line 62: / Line 62: @@
 G4double targetSize  = 0.2*cm;    // Half length of the Target
-Change the target matter variable to tantalum (Tnt)
+Change the target matter variable to tantalum (Ta)
 .) After you check that things are working right  (check physics.cc to be sure it has the Bremsstrahlung (eBrem) process is turned on for the electrons).
@@ Line 74: / Line 74: @@
 /gun/energy 15 MeV
 /event/verbose 0
 /run/beamOn 10000
 exit
@@ Line 87: / Line 86: @@
 <pre>
-.00725373, -0.0493313,-0.201349,0.903937,-0.000406446, -0.00119566, 0.00714295
+.1123 -0.847857 -0.681592 0.172033 -0.0256877 0.00355802 0.109265
-.00825911, 0.256055,0.0515852,1.37989,0.00113305, 0.000415401, 0.00817047
+.11604 -0.890015 -0.650824 0.302384 -0.430069 0.261998 0.995961
-.00689593, 0.267732,-0.614023,1.04238,-0.00423662, -0.00522941, 0.00150271
+.102826 -1.06591 -0.860491 0.812798 -0.0716314 -0.0549312 0.0492417
-.0954614, -0.0828961,0.00149944,-0.403959,-0.0184925, -0.000495819, 0.0936518
+.168739 -1.06702 -0.798629 1.63029 -0.0109706 -0.148751 0.0789028
 </pre>
-create a file for C12 and Tantalum (make may need to rename
+create a file for C12 and Tantalum (may need to rename
 sim.dat to something else or it will be written over when you
 run the program again)
@@ Line 120: / Line 118: @@
      in >> evt.KE >> evt.pos[0] >> evt.pos[1] >> evt.pos[2]   >> evt.mom[0]
   >> evt.mom[1] >> evt.mom[2];
-     /*
+     if(evt.event<3)
        printf( " %d  %f %f %f %f %f %f %f\n", evt.event, evt.KE, evt.pos[0],
   evt.pos[1], evt.pos[2],  evt.mom[0], evt.mom[1], evt.mom[2] );
-     */
      nlines++;
      tree->Fill();

@@ Line 64: / Line 64: @@
 Change the target matter variable to tantalum (Tnt)
-.) After you check that things are working right  (check physics.cc to be it has the Bremsstrahlung (eBrem) process is turned on for the electrons).
+.) After you check that things are working right  (check physics.cc to be sure it has the Bremsstrahlung (eBrem) process is turned on for the electrons).
 Run 10000 events at 15 MeV

@@ Line 2: / Line 2: @@
 [[Simulations_of_Particle_Interactions_with_Matter]]
-The objective of this lab is to alter the physicslist.cc program to
+The objective of this lab is to alter the physics.cc program to
-ONLY include the Bremsstrahlung Physics process in order to determine
+ONLY include the G4EmStandardPhysics process in order to determine
 the photon energy distribution due to bremsstrahlung and compare
 that distribution with experiment.
@@ Line 64: / Line 64: @@
 Change the target matter variable to tantalum (Tnt)
-.) After you check that things are working right  (check physicslist.cc to be sure that only the Bremsstrahlung process is turned on for the electrons).
+.) After you check that things are working right  (check physics.cc to be it has the Bremsstrahlung (eBrem) process is turned on for the electrons).
 Run 10000 events at 15 MeV

@@ Line 52: / Line 52: @@
 make sure the above code isn't embedded in another if statement
-.) Now edit src/ExN02DetectorConstruction.cc
+.) Now edit construction.cc
 and add the material Tantalum to the list
@@ Line 64: / Line 64: @@
 Change the target matter variable to tantalum (Tnt)
-.) After you check that things are working right  (check ExN02PhysicsList.cc to be sure that only the Bremsstrahlung process is turned on for the electrons).
+.) After you check that things are working right  (check physicslist.cc to be sure that only the Bremsstrahlung process is turned on for the electrons).
 Run 10000 events at 15 MeV

@@ Line 2: / Line 2: @@
 [[Simulations_of_Particle_Interactions_with_Matter]]
-The objective of this lab is to alter the ExN02PhysicsList.cc program to
+The objective of this lab is to alter the physicslist.cc program to
 ONLY include the Bremsstrahlung Physics process in order to determine
 the photon energy distribution due to bremsstrahlung and compare

@@ Line 107: / Line 107: @@
    };
    ifstream in;
-   in.open("Brem.txt");
+   in.open("sim.dat");
    evt_t evt;
    Int_t nlines=0;

@@ Line 19: / Line 19: @@
 function
-	void ExN02SteppingVerbose::StepInfo()
 <pre>
-  if( fTrack->GetDefinition()->GetPDGEncoding()==22 &&  fTrack->GetCurrentStepNumber()==1 && fTrack->GetKineticEnergy()>0)
+   if(step->GetTrack()->GetParticleDefinition()->GetParticleName()=="e-" && step->GetPostStepPoint()->GetProcessDefinedStep()->GetProcessName()=="eBrem")
-−
+      {
-      //      G4cout  << "  Photon Energy "
+      if(step->GetNumberOfSecondariesInCurrentStep()>0)
-      outfile <<   fTrack->GetKineticEnergy() << "    "
-       << fTrack->GetPosition().x()<< "    "
+            auto secondary = step->GetSecondaryInCurrentStep();
-       << fTrack->GetPosition().y()<< "    "
+            size_t size_secondary = (*secondary).size();
-       << fTrack->GetPosition().z()<< "    "
+            if (size_secondary){
-       << fTrack->GetMomentum().x() << "    "
+              for (size_t i=0; i<(size_secondary);i++){
-       << fTrack->GetMomentum().y() << "    "
+                auto secstep = (*secondary)[i];
-       << fTrack->GetMomentum().z() << "    "
+                outfile
-       << G4endl;
+                 << secstep->GetKineticEnergy()  << ", "
+                  << secstep->GetPosition().x()<< ","
 </pre>
@@ Line 47: / Line 57: @@
 set target length to 4 mm
- G4double targetSize  = 0.4*cm;    // Half length of the Target
+G4double targetSize  = 0.2*cm;    // Half length of the Target
 Change the target matter variable to tantalum (Tnt)
@@ Line 70: / Line 78: @@
 now you can run the simulation in "batch mode" ie without visualization and re-direct the output to a file
-ie: > ./exampleN02 run1.mac > /dev/null &
+ie: > ./sim run.mac > /dev/null &
-.) You may have a file called Range.date which has entries
+.) You may have a file called sim.dat which has entries
 that look like
 <pre>
-.082831    -0.102156    -0.155741    -800    -0.00347244    -0.00405495    0.0826588
+.00725373, -0.0493313,-0.201349,0.903937,-0.000406446, -0.00119566, 0.00714295
-.346969    0.499903    -0.474851    -800    0.0683589    -0.0569303    0.335371
+.00825911, 0.256055,0.0515852,1.37989,0.00113305, 0.000415401, 0.00817047
-.332485    -172.26    -254.795    800    -0.0621649    -0.0604049    0.320987
+.00689593, 0.267732,-0.614023,1.04238,-0.00423662, -0.00522941, 0.00150271
 </pre>
 create a file for C12 and Tantalum (make may need to rename
-SigmaR.txt to something else or it will be written over when you
+sim.dat to something else or it will be written over when you
 run the program again)

@@ Line 16: / Line 16: @@
 energy, position, and momentum.
-.) In the file src/ExN02SteppingVerbose.cc add the code below to the
+.) In the file stepping.cc add the code below to the
 function
@@ Line 42: / Line 42: @@
 and add the material Tantalum to the list
-  G4Material* Tnt =
+   //    TargetMater=nist->FindOrBuildMaterial("G4_Ta");
-  new G4Material("Tantalum", z=73., a= 180.9479*g/mole, density= 16.654*g/cm3);
+    TargetMater=nist->FindOrBuildMaterial("G4_C");
 set target length to 4 mm
-  fTargetLength  = 0.4 * cm;                        // Full length of Target
+ G4double targetSize  = 0.4*cm;    // Half length of the Target

@@ Line 147: / Line 147: @@
 respect to the Z-axis
-root[0]Brem->Draw("atan((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14","pz>0");
+root[0]Brem->Draw("asin((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14","pz>0");
@@ Line 197: / Line 197: @@
 now fill the histgram with the data
-root[2]Brem->Draw("atan((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14 >> BremAngle_C12","pz>0");
+root[2]Brem->Draw("asin((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14 >> BremAngle_C12","pz>0");
 you will see a histogram save under the file "C12.root"
@@ Line 214: / Line 214: @@
 now fill the histgram with the data
-root[2]Brem->Draw("atan((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14 >> BremAngle_Tant","pz>0");
+root[2]Brem->Draw("asin((px*px+py*py)/(px*px+py*py+pz*pz))*180/3.14 >> BremAngle_Tant","pz>0");
 you will see a histogram save under the file "Tantalum.root"