Line Source on generator particle gun

Getting Started
1

I have a detector to get the gamma spectrum from a Cs-137 (662 KeV) point source. But, now I have to change my point source into a line source (at least 2 cm long line source)?

I have attached my generator.cc code, is it correct? does my code will simulate 20 Cs-137 with 2 mm separations?

MyPrimaryGenerator::MyPrimaryGenerator()
{
fParticleGun = new G4ParticleGun(1);

}

MyPrimaryGenerator::~MyPrimaryGenerator()
{
delete fParticleGun;
}

void MyPrimaryGenerator::GeneratePrimaries(G4Event *anEvent)
{

G4int Z = 55;
G4int A = 137;    

    G4double charge   = 0.*eplus;
    G4double energy = 0.662*MeV;

G4ParticleDefinition* particle;
G4ParticleDefinition* ion = G4IonTable::GetIonTable()->GetIon(Z,A,energy);
G4double x0 = 0.0*mm;
G4double x1 = 2.0*mm;
G4double x = x0 + (x1-x0)*G4UniformRand()*20;

    G4ThreeVector pos(0., 0., x);
    G4ThreeVector mom(0., 0., 1.);


    fParticleGun->SetParticlePosition(pos);
    fParticleGun->SetParticleDefinition(ion);
    fParticleGun->SetParticleCharge(charge);


fParticleGun->GeneratePrimaryVertex(anEvent);

}

3

I’ve closed this as the question has already been asked here: Cs-137 Line Source