diff --git a/cosmic_rays.cc b/cosmic_rays.cc
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+//
+// ********************************************************************
+// * License and Disclaimer                                           *
+// *                                                                  *
+// * The  Geant4 software  is  copyright of the Copyright Holders  of *
+// * the Geant4 Collaboration.  It is provided  under  the terms  and *
+// * conditions of the Geant4 Software License,  included in the file *
+// * LICENSE and available at  http://cern.ch/geant4/license .  These *
+// * include a list of copyright holders.                             *
+// *                                                                  *
+// * Neither the authors of this software system, nor their employing *
+// * institutes,nor the agencies providing financial support for this *
+// * work  make  any representation or  warranty, express or implied, *
+// * regarding  this  software system or assume any liability for its *
+// * use.  Please see the license in the file  LICENSE  and URL above *
+// * for the full disclaimer and the limitation of liability.         *
+// *                                                                  *
+// * This  code  implementation is the result of  the  scientific and *
+// * technical work of the GEANT4 collaboration.                      *
+// * By using,  copying,  modifying or  distributing the software (or *
+// * any work based  on the software)  you  agree  to acknowledge its *
+// * use  in  resulting  scientific  publications,  and indicate your *
+// * acceptance of all terms of the Geant4 Software license.          *
+// ********************************************************************
+//
+//
+/// \file exampleB1.cc
+/// \brief Main program of the B1 example
+
+#include "B1DetectorConstruction.hh"
+#include "B1ActionInitialization.hh"
+
+#ifdef G4MULTITHREADED
+#include "G4MTRunManager.hh"
+#else
+#include "G4RunManager.hh"
+#endif
+
+#include "G4UImanager.hh"
+#include "QBBC.hh"
+#include "FTFP_BERT.hh"
+
+#include "G4VisExecutive.hh"
+#include "G4UIExecutive.hh"
+
+#include "Randomize.hh"
+
+//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
+
+int main(int argc,char** argv)
+{
+  G4double p, e_p, e_m, mu_p, mu_m = 0;
+  // Detect interactive mode (if no arguments) and define UI session
+  //
+  G4UIExecutive* ui = 0;
+  if ( argc == 1 ) {
+    ui = new G4UIExecutive(argc, argv);
+  }
+
+  // Choose the Random engine
+  G4Random::setTheEngine(new CLHEP::RanecuEngine);
+  
+  // Construct the default run manager
+  //
+#ifdef G4MULTITHREADED
+  G4MTRunManager* runManager = new G4MTRunManager;
+#else
+  G4RunManager* runManager = new G4RunManager;
+#endif
+
+  // Set mandatory initialization classes
+  //
+  // Detector construction
+  runManager->SetUserInitialization(new B1DetectorConstruction());
+
+  // Physics list - FTFP_BERT - p/shower
+  // added verbose to the physics list
+  G4int verbose = 0;
+  G4VModularPhysicsList* physicsList = new FTFP_BERT;
+  runManager->SetUserInitialization(physicsList);
+    
+  // User action initialization
+  runManager->SetUserInitialization(new B1ActionInitialization());
+  
+  // Initialize visualization
+  // (if you don't want the image, just delete the G4VisManager objetc and everything that concerns it)
+  G4VisManager* visManager = new G4VisExecutive;
+  // G4VisExecutive can take a verbosity argument - see /vis/verbose guidance.
+  // G4VisManager* visManager = new G4VisExecutive("Quiet");
+  visManager->Initialize();
+
+  // Get the pointer to the User Interface manager
+  G4UImanager* UImanager = G4UImanager::GetUIpointer();
+
+  // Process macro or start UI session
+  // (you can delete this if-clause too.)
+  if ( ! ui ) { 
+    // batch mode
+    G4String command = "/control/execute ";
+    G4String fileName = argv[1];
+    UImanager->ApplyCommand(command+fileName);
+  }
+  else { 
+    // interactive mode
+    UImanager->ApplyCommand("/control/execute init_vis.mac");
+    ui->SessionStart();
+    delete ui;
+  }
+
+  // Job termination
+  // Free the store: user actions, physics_list and detector_description are
+  // owned and deleted by the run manager, so they should not be deleted 
+  // in the main() program !
+  
+  delete visManager; //(delete this line too if you don't want image).
+  delete runManager;
+}
+
+//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.....