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LaserBeamsTEC2 Class Reference

Laser Beams in the left Endcap. More...

#include <Alignment/LaserAlignmentSimulation/interface/LaserBeamsTEC2.h>

List of all members.

Public Member Functions

void GeneratePrimaries (G4Event *myEvent)
 shoot optical photons into the detector at the beginning of an event
 LaserBeamsTEC2 (G4int nPhotonsInGun, G4int nPhotonsInBeam, G4double PhotonEnergy)
 constructor
 LaserBeamsTEC2 ()
 default constructor
void setOptPhotonPolar (G4double Angle)
 set the polarisation of the photons
 ~LaserBeamsTEC2 ()
 destructor

Private Attributes

DRand48Engine * theDRand48Engine
G4int thenParticle
G4int thenParticleInGun
G4ParticleGun * theParticleGun
G4double thePhotonEnergy

Detailed Description

Laser Beams in the left Endcap.

Date
2007/06/11 14:44:28
Revision
1.3
Author:
Maarten Thomas

Definition at line 21 of file LaserBeamsTEC2.h.

Constructor & Destructor Documentation

LaserBeamsTEC2::LaserBeamsTEC2 (  ) 

default constructor

Definition at line 20 of file LaserBeamsTEC2.cc.

00021 { 
00022   G4int nPhotonsGun = 1;
00023   G4int nPhotonsBeam = 1;
00024   G4double Energy = 1.15 * eV;
00025   // call constructor with options
00026   LaserBeamsTEC2(nPhotonsGun, nPhotonsBeam, Energy);
00027 }

LaserBeamsTEC2::LaserBeamsTEC2 ( G4int  nPhotonsInGun,
G4int  nPhotonsInBeam,
G4double  PhotonEnergy 
)

constructor

Definition at line 29 of file LaserBeamsTEC2.cc.

References setOptPhotonPolar(), theDRand48Engine, thenParticle, thenParticleInGun, theParticleGun, and thePhotonEnergy.

00029                                                                                                : thenParticleInGun(0),
00030                                                                                                    thenParticle(0),
00031                                                                                                    thePhotonEnergy(0),
00032                                                                                                    theParticleGun(),
00033                                                                                                    theDRand48Engine()
00034 {
00035   /* *********************************************************************** */
00036   /*  initialize and configure the particle gun                              */
00037   /* *********************************************************************** */
00038 
00039   // the Photon energy
00040   thePhotonEnergy = PhotonEnergy;
00041 
00042   // number of particles in the Laser beam
00043   thenParticleInGun = nPhotonsInGun;
00044 
00045   // number of particles in one beam. ATTENTION: each beam contains nParticleInGun with the same
00046   // startpoint and direction. nParticle gives the number of particles in the beam with a different
00047   // startpoint. They are used to simulate the gaussian beamprofile of the Laser Beams.
00048   thenParticle = nPhotonsInBeam;
00049 
00050   // create the particle gun
00051   theParticleGun = new G4ParticleGun(thenParticleInGun);
00052 
00053   // default kinematics
00054   G4ParticleTable * theParticleTable = G4ParticleTable::GetParticleTable();
00055   G4ParticleDefinition * theOpticalPhoton = theParticleTable->FindParticle("opticalphoton");
00056 
00057   theParticleGun->SetParticleDefinition(theOpticalPhoton);
00058   theParticleGun->SetParticleTime(0.0 * ns);
00059   theParticleGun->SetParticlePosition(G4ThreeVector(-500.0 * cm, 0.0 * cm, 0.0 * cm));
00060   theParticleGun->SetParticleMomentumDirection(G4ThreeVector(5.0, 3.0, 0.0));
00061   theParticleGun->SetParticleEnergy(10.0 * keV);
00062   setOptPhotonPolar(90.0);
00063 
00064   // initialize the random number engine
00065   theDRand48Engine = new DRand48Engine();
00066 }

LaserBeamsTEC2::~LaserBeamsTEC2 (  ) 

destructor

Definition at line 68 of file LaserBeamsTEC2.cc.

References theDRand48Engine, and theParticleGun.

00069 {
00070   if ( theParticleGun != 0 )  { delete theParticleGun; }
00071   if ( theDRand48Engine != 0 ) { delete theDRand48Engine; }
00072 }

Member Function Documentation

void LaserBeamsTEC2::GeneratePrimaries ( G4Event *  myEvent  ) 

shoot optical photons into the detector at the beginning of an event

Definition at line 74 of file LaserBeamsTEC2.cc.

References funct::cos(), setOptPhotonPolar(), funct::sin(), theDRand48Engine, thenParticle, theParticleGun, and thePhotonEnergy.

Referenced by LaserPrimaryGeneratorAction::GeneratePrimaries().

00075 {
00076   // this function is called at the beginning of an Event in LaserAlignment::upDate(const BeginOfEvent * myEvent)
00077 
00078   // use the random number generator service of the framework
00079   edm::Service<edm::RandomNumberGenerator> rng;
00080   uint seed = rng->mySeed();
00081 
00082   // set the seed
00083   theDRand48Engine->setSeed(seed);
00084 
00085 
00086   // number of LaserRings and Laserdiodes
00087   const G4int nLaserRings = 2;
00088   const G4int nLaserBeams = 8;
00089 
00090   // z position of the sixth Tracker Endcap Disc, where the Laserdiodes are positioned
00091   G4double LaserPositionZ = -2057.5 * mm;
00092 
00093   // Radius of the inner and outer Laser ring
00094   G4double LaserRingRadius[nLaserRings] = {564.0 * mm, 840.0 * mm};
00095 
00096   // phi position of the first Laserdiode
00097   G4double LaserPhi0 = 0.392699082;
00098 
00099   // width of the LaserBeams
00100   G4double LaserRingSigmaX[nLaserRings] = {0.5 * mm, 0.5 * mm};
00101   G4double LaserRingSigmaY[nLaserRings] = {0.5 * mm, 0.5 * mm};
00102 
00103   // get the definition of the optical photon
00104   G4ParticleTable * theParticleTable = G4ParticleTable::GetParticleTable();
00105   G4ParticleDefinition * theOpticalPhoton= theParticleTable->FindParticle("opticalphoton");
00106 
00107   // loop over the LaserRings
00108   for (int theRing = 0; theRing < nLaserRings; theRing++)
00109     {
00110       // loop over the LaserBeams
00111       for (int theBeam = 0; theBeam < nLaserBeams; theBeam++)
00112         {
00113           // code for forward and backward beam
00114           // calculate the right phi for the current beam
00115           G4double LaserPositionPhi = LaserPhi0 + G4double(theBeam * G4double(G4double(2 * M_PI) / nLaserBeams));
00116 
00117           // calculate x and y position for the current beam
00118           G4double LaserPositionX = cos(LaserPositionPhi) * LaserRingRadius[theRing];
00119           G4double LaserPositionY = sin(LaserPositionPhi) * LaserRingRadius[theRing];
00120 
00121           // loop over all the particles in one beam
00122           for (int theParticle = 0; theParticle < thenParticle; theParticle++)
00123             {
00124               // get randomnumbers  and calculate the position
00125               RandGaussQ aGaussObjX( *theDRand48Engine, LaserPositionX, LaserRingSigmaX[theRing] );
00126               RandGaussQ aGaussObjY( *theDRand48Engine, LaserPositionY, LaserRingSigmaY[theRing] );
00127 
00128               G4double theXPosition = aGaussObjX.fire();
00129               G4double theYPosition = aGaussObjY.fire();
00130               G4double theZPosition = LaserPositionZ;
00131 
00132               // set the properties of the newly created particle
00133               theParticleGun->SetParticleDefinition(theOpticalPhoton);
00134               theParticleGun->SetParticleTime(0.0 * ns);
00135               theParticleGun->SetParticlePosition(G4ThreeVector(theXPosition, theYPosition, theZPosition));
00136               theParticleGun->SetParticleEnergy(thePhotonEnergy);
00137 
00138               // loop over both directions of the beam
00139               for (int theDirection = 0; theDirection < 2; theDirection++)
00140                 {
00141                   // shoot in both beam directions ...
00142                   if (theDirection == 0)  // shoot in forward direction (+z)
00143                     {
00144                       theParticleGun->SetParticleMomentumDirection(G4ThreeVector(0.0, 0.0, 1.0));
00145                       // set the polarization
00146                       setOptPhotonPolar(90.0);
00147                       // generate the particle
00148                       theParticleGun->GeneratePrimaryVertex(myEvent);
00149                     }
00150 
00151                   if (theDirection == 1)  // shoot in backward direction (-z)
00152                     {
00153                       theParticleGun->SetParticleMomentumDirection(G4ThreeVector(0.0, 0.0, -1.0));
00154                       // set the polarization
00155                       setOptPhotonPolar(90.0);
00156                       // generate the particle
00157                       theParticleGun->GeneratePrimaryVertex(myEvent);
00158                     }
00159                 } // end loop over both beam directions
00160             } // end loop over particles in beam
00161         } // end loop over beams
00162     } // end loop over rings
00163 }

void LaserBeamsTEC2::setOptPhotonPolar ( G4double  Angle  ) 

set the polarisation of the photons

Definition at line 165 of file LaserBeamsTEC2.cc.

References funct::cos(), funct::sin(), funct::sqrt(), and theParticleGun.

Referenced by GeneratePrimaries(), and LaserBeamsTEC2().

00166 {
00167   /* *********************************************************************** */
00168   /*   to get optical processes working properly, you have to make sure      *
00169    *   that the photon polarisation is defined.                              */
00170   /* *********************************************************************** */
00171 
00172   // first check if we have an optical photon
00173   if ( theParticleGun->GetParticleDefinition()->GetParticleName() != "opticalphoton" )
00174     { 
00175       edm::LogWarning("SimLaserAlignment:LaserBeamsTEC2") << "<LaserBeamsTEC2::setOptPhotonPolar()>: WARNING! The ParticleGun is not an optical photon";
00176       return;
00177     }
00178 
00179 //   G4cout << "  AC1CMS: The ParticleGun is an " << theParticleGun->GetParticleDefinition()->GetParticleName();
00180   G4ThreeVector normal(1.0, 0.0, 0.0);
00181   G4ThreeVector kphoton = theParticleGun->GetParticleMomentumDirection();
00182   G4ThreeVector product = normal.cross(kphoton);
00183   G4double modul2 = product * product;
00184 
00185   G4ThreeVector e_perpendicular(0.0, 0.0, 1.0);
00186   
00187   if ( modul2 > 0.0 ) { e_perpendicular = (1.0 / sqrt(modul2)) * product; }
00188   
00189   G4ThreeVector e_parallel = e_perpendicular.cross(kphoton);
00190 
00191   G4ThreeVector polar = cos(Angle) * e_parallel + sin(Angle) * e_perpendicular;
00192   
00193 //   G4cout << ", the polarization = " << polar << G4endl;
00194   theParticleGun->SetParticlePolarization(polar);
00195 }

Member Data Documentation

DRand48Engine* LaserBeamsTEC2::theDRand48Engine [private]

Definition at line 46 of file LaserBeamsTEC2.h.

Referenced by GeneratePrimaries(), LaserBeamsTEC2(), and ~LaserBeamsTEC2().

G4int LaserBeamsTEC2::thenParticle [private]

Definition at line 39 of file LaserBeamsTEC2.h.

Referenced by GeneratePrimaries(), and LaserBeamsTEC2().

G4int LaserBeamsTEC2::thenParticleInGun [private]

Definition at line 38 of file LaserBeamsTEC2.h.

Referenced by LaserBeamsTEC2().

G4ParticleGun* LaserBeamsTEC2::theParticleGun [private]

Definition at line 43 of file LaserBeamsTEC2.h.

Referenced by GeneratePrimaries(), LaserBeamsTEC2(), setOptPhotonPolar(), and ~LaserBeamsTEC2().

G4double LaserBeamsTEC2::thePhotonEnergy [private]

Definition at line 40 of file LaserBeamsTEC2.h.

Referenced by GeneratePrimaries(), and LaserBeamsTEC2().

The documentation for this class was generated from the following files:
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