#include <PndGasGenerator.h>

Inheritance diagram for PndGasGenerator:

Public Member Functions
	PndGasGenerator ()

	PndGasGenerator (Int_t pdgid, Int_t mult=1)

virtual	~PndGasGenerator ()

void	SetPDGType (Int_t pdg)

void	SetMultiplicity (Int_t mult)

void	SetPRange (Double32_t pmin=0, Double32_t pmax=10)

void	SetPhiRange (Double32_t phimin=0, Double32_t phimax=360)

void	SetThetaRange (Double32_t thetamin=0, Double32_t thetamax=90)

void	SetCosTheta ()

void	SetZRange (Double32_t zmin=0, Double32_t zmax=10)

void	SetRadius (Double32_t radius=0.2)

void	SetDebug (Bool_t debug=0)

Bool_t	Init ()

virtual Bool_t	ReadEvent (FairPrimaryGenerator *primGen)

Private Member Functions
	ClassDef (PndGasGenerator, 1)

Private Attributes
Int_t	fPDGType

Int_t	fMult

Double32_t	fPDGMass

Double32_t	fPhiMin

Double32_t	fPhiMax

Double32_t	fPMin

Double32_t	fPMax

Double32_t	fThetaMin

Double32_t	fThetaMax

Double32_t	fX

Double32_t	fY

Double32_t	fZ

Double32_t	fRadius

Bool_t	fThetaRangeIsSet

Bool_t	fCosThetaIsSet

Bool_t	fPRangeIsSet

Double32_t	fZMin

Double32_t	fZMax

Bool_t	fDebug

TF1 *	fDensityProfile

Detailed Description

Definition at line 30 of file PndGasGenerator.h.

Constructor & Destructor Documentation

PndGasGenerator::PndGasGenerator ( )

Default constructor.

Definition at line 18 of file PndGasGenerator.cxx.

                                  :
   fPDGType(0),fMult(0),fPDGMass(0),
   fPhiMin(0),fPhiMax(0),
   fPMin(0),fPMax(0),fThetaMin(0),fThetaMax(0),fX(0),fY(0),fZ(0),
   fThetaRangeIsSet(0),
   fCosThetaIsSet(0),fPRangeIsSet(0),
   fZMin(0.), fZMax(10.), fDensityProfile(NULL)
 {
   // Default constructor
 }

PndGasGenerator::PndGasGenerator	(	Int_t	pdgid,
		Int_t	mult = `1`
	)

Constructor with PDG-ID, multiplicity

Parameters

pdgid	Particle type (PDG encoding)
mult	Multiplicity (default is 1)

Definition at line 30 of file PndGasGenerator.cxx.

References SetPhiRange().

                                                         :
   fPDGType(pdgid),fMult(mult),fPDGMass(0),
   fPMin(0),fPMax(0),fX(0),fY(0),fZ(0),
   fThetaRangeIsSet(0),
   fCosThetaIsSet(0),fPRangeIsSet(0),
   fZMin(0.), fZMax(10.), fDensityProfile(NULL)
 {
   // Constructor. Set default kinematics limits
   SetPhiRange  ();
 }

virtual PndGasGenerator::~PndGasGenerator ( )

inlinevirtual

Destructor

Definition at line 45 of file PndGasGenerator.h.

45 {};

Member Function Documentation

PndGasGenerator::ClassDef	(	PndGasGenerator	,
		1
	)

private

Bool_t PndGasGenerator::Init ( )

Initializer

Definition at line 42 of file PndGasGenerator.cxx.

References fDensityProfile, fPDGMass, fPDGType, fPhiMax, fPhiMin, fZMax, fZMin, and particle.

 {
   // Initialize generator
 
   if (fPhiMax-fPhiMin>360)
     Fatal("Init()","PndGasGenerator: phi range is too wide: %f<phi<%f",
           fPhiMin,fPhiMax);
 
   // Check for particle type
   TDatabasePDG* pdgBase = TDatabasePDG::Instance();
   TParticlePDG *particle = pdgBase->GetParticle(fPDGType);
   if (! particle) Fatal("PndGasGenerator","PDG code %d not defined.",fPDGType);
   fPDGMass = particle->Mass();
 
   // create the density profile histogram used later to get the random 
   // z position
   fDensityProfile = new TF1("Density Profile","exp(-0.5*((x)/4)**2)",fZMin,fZMax);  
   return kTRUE;
 }

Bool_t PndGasGenerator::ReadEvent ( FairPrimaryGenerator * primGen )

virtual

Creates an event with given type and multiplicity.

Parameters

primGen pointer to the FairPrimaryGenerator

Definition at line 63 of file PndGasGenerator.cxx.

References acos(), CAMath::Cos(), cos(), fCosThetaIsSet, fDebug, fDensityProfile, fMult, fPDGType, fPhiMax, fPhiMin, fPMax, fPMin, fRadius, fThetaMax, fThetaMin, fX, fY, fZ, phi, printf(), pt(), pz, CAMath::Sin(), and theta.

 {
   // Generate one event: produce primary particles emitted from one vertex.
   // Primary particles are distributed uniformly along
   // those kinematics variables which were limitted by setters.
   // if SetCosTheta() function is used, the distribution will be uniform in cos(theta)
   
   Double32_t pabs, phi, pt, theta=0, px, py, pz;
   //Double32_t eta, pinv, y, mt=0; //[R.K. 01/2017] unused variable?
 
   // Generate particles
   for (Int_t k = 0; k < fMult; k++) {
 
     phi = gRandom->Uniform(fPhiMin,fPhiMax) * TMath::DegToRad();
 
     pabs = gRandom->Uniform(fPMin,fPMax);
    
     
     if (fCosThetaIsSet) {
       theta = acos(gRandom->Uniform(cos(fThetaMin* TMath::DegToRad()),cos(fThetaMax* TMath::DegToRad())));
     } else {
       theta = gRandom->Uniform(fThetaMin,fThetaMax) * TMath::DegToRad();
     }
 
     
 
     pz = pabs*TMath::Cos(theta);
     pt = pabs*TMath::Sin(theta);
 
     px = pt*TMath::Cos(phi);
     py = pt*TMath::Sin(phi);
 
     // Random 2D point in a circle of radius r (simple beamprofile)
     gRandom->Circle(fX, fY, fRadius);
 
     // calculate fZ according to some (probability) density function of the gas
     fZ=fDensityProfile->GetRandom(); 
 
     if (fDebug)
       printf("GasGen: kf=%d, p=(%.2f, %.2f, %.2f) GeV, x=(%.1f, %.1f, %.1f) cm\n",
              fPDGType, px, py, pz, fX, fY, fZ);
 
 
   
     primGen->AddTrack(fPDGType, px, py, pz, fX, fY, fZ);
      
 
 
   }
   return kTRUE;
 
 }