#include <TH1F.h>
#include <TF1.h>
#include <TCanvas.h>
+#include <TParticle.h>
+#include "AliConst.h"
#include "AliCollisionGeometry.h"
+#include "AliStack.h"
+#include "AliRun.h"
+#include "AliMC.h"
#include "AliGenSlowNucleons.h"
#include "AliSlowNucleonModel.h"
fMomentum(0.),
fBeta(0.),
fPmax (0.),
- fATarget (0.),
- fZTarget (0.),
fCharge(0),
- fProtonDirection(0.),
+ fProtonDirection(1.),
fTemperatureG(0.),
fBetaSourceG(0.),
fTemperatureB(0.),
fThetaDistribution(),
fCosThetaGrayHist(),
fCosTheta(),
+ fBeamCrossingAngle(0.),
+ fBeamDivergence(0.),
+ fBeamDivEvent(0.),
+ fSmearMode(2),
fSlowNucleonModel(0)
{
// Default constructor
fMomentum(0.),
fBeta(0.),
fPmax (10.),
- fATarget (208.),
- fZTarget (82.),
fCharge(1),
- fProtonDirection(0.),
- fTemperatureG(0.04),
+ fProtonDirection(1.),
+ fTemperatureG(0.05),
fBetaSourceG(0.05),
- fTemperatureB(0.004),
+ fTemperatureB(0.005),
fBetaSourceB(0.),
fNgp(0),
fNgn(0),
fThetaDistribution(),
fCosThetaGrayHist(),
fCosTheta(),
+ fBeamCrossingAngle(0.),
+ fBeamDivergence(0.),
+ fBeamDivEvent(0.),
+ fSmearMode(2),
fSlowNucleonModel(new AliSlowNucleonModel())
+
{
// Constructor
fName = "SlowNucleons";
//
// Initialization
//
- Float_t kMass = TDatabasePDG::Instance()->GetParticle(kProton)->Mass();
- fMomentum = fCMS/2. * fZTarget / fATarget;
+ Double_t kMass = TDatabasePDG::Instance()->GetParticle(kProton)->Mass();
+ fMomentum = fCMS/2. * Float_t(fZTarget) / Float_t(fATarget);
fBeta = fMomentum / TMath::Sqrt(kMass * kMass + fMomentum * fMomentum);
+ //printf(" fMomentum %f fBeta %1.10f\n",fMomentum, fBeta);
if (fDebug) {
fDebugHist1 = new TH2F("DebugHist1", "nu vs N_slow", 100, 0., 100., 20, 0., 20.);
fDebugHist2 = new TH2F("DebugHist2", "b vs N_slow", 100, 0., 100., 15, 0., 15.);
"(2./3.14159265358979312)/(exp(2./3.14159265358979312)-exp(-2./3.14159265358979312))*exp(2.*x/3.14159265358979312)",
-1., 1.);
}
+
+ printf("\n AliGenSlowNucleons: applying crossing angle %f mrad to slow nucleons\n",fBeamCrossingAngle*1000.);
}
void AliGenSlowNucleons::FinishRun()
TCanvas *c = new TCanvas("c","Canvas 1",400,10,600,700);
c->Divide(2,1);
c->cd(1);
- fDebugHist1->Draw();
+ fDebugHist1->Draw("colz");
c->cd(2);
fDebugHist2->Draw();
c->cd(3);
//
if (fCollisionGeometry) {
Float_t b = fCollisionGeometry->ImpactParameter();
- Int_t nn = fCollisionGeometry->NN();
- Int_t nwn = fCollisionGeometry->NwN();
- Int_t nnw = fCollisionGeometry->NNw();
- Int_t nwnw = fCollisionGeometry->NwNw();
-
- fSlowNucleonModel->GetNumberOfSlowNucleons(fCollisionGeometry, fNgp, fNgn, fNbp, fNbn);
+ // Int_t nn = fCollisionGeometry->NN();
+ // Int_t nwn = fCollisionGeometry->NwN();
+ // Int_t nnw = fCollisionGeometry->NNw();
+ // Int_t nwnw = fCollisionGeometry->NwNw();
+
+ // (1) Sikler' model
+ if(fSmearMode==0) fSlowNucleonModel->GetNumberOfSlowNucleons(fCollisionGeometry, fNgp, fNgn, fNbp, fNbn);
+ // (2) Model inspired on exp. data at lower energy (Gallio-Oppedisano)
+ // --- smearing the Ncoll fron generator used as input
+ else if(fSmearMode==1) fSlowNucleonModel->GetNumberOfSlowNucleons2(fCollisionGeometry, fNgp, fNgn, fNbp, fNbn);
+ // --- smearing directly Nslow
+ else if(fSmearMode==2) fSlowNucleonModel->GetNumberOfSlowNucleons2s(fCollisionGeometry, fNgp, fNgn, fNbp, fNbn);
if (fDebug) {
- printf("Nucleons %d %d %d %d \n", fNgp, fNgn, fNbp, fNbn);
- fDebugHist1->Fill(Float_t(fNgp + fNgn + fNbp + fNbn), fCollisionGeometry->NwN(), 1.);
+ //printf("Collision Geometry %f %d %d %d %d\n", b, nn, nwn, nnw, nwnw);
+ printf("Slow nucleons: %d grayp %d grayn %d blackp %d blackn \n", fNgp, fNgn, fNbp, fNbn);
+ fDebugHist1->Fill(Float_t(fNgp + fNgn + fNbp + fNbn), fCollisionGeometry->NNw(), 1.);
fDebugHist2->Fill(Float_t(fNgp + fNgn + fNbp + fNbn), b, 1.);
- printf("AliGenSlowNucleons: Impact parameter from Collision Geometry %f %d %d %d %d\n",
- b, nn, nwn, nnw, nwnw);
+
}
}
//
- Float_t p[3], theta=0;
+ Float_t p[3] = {0., 0., 0.}, theta=0;
Float_t origin[3] = {0., 0., 0.};
+ Float_t time = 0.;
Float_t polar [3] = {0., 0., 0.};
Int_t nt, i, j;
Int_t kf;
-
+
+ // Extracting 1 value per event for the divergence angle
+ Double_t rvec = gRandom->Gaus(0.0, 1.0);
+ fBeamDivEvent = fBeamDivergence * TMath::Abs(rvec);
+ printf("\n AliGenSlowNucleons: applying beam divergence %f mrad to slow nucleons\n",fBeamDivEvent*1000.);
+
if(fVertexSmear == kPerEvent) {
Vertex();
for (j=0; j < 3; j++) origin[j] = fVertex[j];
+ time = fTime;
} // if kPerEvent
//
// Gray protons
GenerateSlow(fCharge, fTemperatureG, fBetaSourceG, p, theta);
if (fDebug) fCosThetaGrayHist->Fill(TMath::Cos(theta));
PushTrack(fTrackIt, -1, kf, p, origin, polar,
- 0., kPNoProcess, nt, 1.);
+ time, kPNoProcess, nt, 1.,-2);
KeepTrack(nt);
+ SetProcessID(nt,kGrayProcess);
}
//
// Gray neutrons
GenerateSlow(fCharge, fTemperatureG, fBetaSourceG, p, theta);
if (fDebug) fCosThetaGrayHist->Fill(TMath::Cos(theta));
PushTrack(fTrackIt, -1, kf, p, origin, polar,
- 0., kPNoProcess, nt, 1.);
+ time, kPNoProcess, nt, 1.,-2);
KeepTrack(nt);
+ SetProcessID(nt,kGrayProcess);
}
//
// Black protons
for(i = 0; i < fNbp; i++) {
GenerateSlow(fCharge, fTemperatureB, fBetaSourceB, p, theta);
PushTrack(fTrackIt, -1, kf, p, origin, polar,
- 0., kPNoProcess, nt, 1.);
+ time, kPNoProcess, nt, 1.,-1);
KeepTrack(nt);
+ SetProcessID(nt,kBlackProcess);
}
//
// Black neutrons
for(i = 0; i < fNbn; i++) {
GenerateSlow(fCharge, fTemperatureB, fBetaSourceB, p, theta);
PushTrack(fTrackIt, -1, kf, p, origin, polar,
- 0., kPNoProcess, nt, 1.);
+ time, kPNoProcess, nt, 1.,-1);
KeepTrack(nt);
+ SetProcessID(nt,kBlackProcess);
}
}
Three-momentum [GeV/c] is given back in q[3]
*/
+ //printf("Generating slow nuc. with: charge %d. temp. %1.4f, beta %f \n",charge,T,beta);
+
Double_t m, pmax, p, f, phi;
TDatabasePDG * pdg = TDatabasePDG::Instance();
const Double_t kMassProton = pdg->GetParticle(kProton) ->Mass();
/* Momentum at maximum of Maxwell-distribution */
- pmax = TMath::Sqrt(2*T*(T+sqrt(T*T+m*m)));
+ pmax = TMath::Sqrt(2*T*(T+TMath::Sqrt(T*T+m*m)));
/* Try until proper momentum */
/* for lack of primitive function of the Maxwell-distribution */
//
phi = 2. * TMath::Pi() * Rndm();
+
/* Determine momentum components in system of the moving source */
q[0] = p * TMath::Sin(theta) * TMath::Cos(phi);
q[1] = p * TMath::Sin(theta) * TMath::Sin(phi);
q[2] = p * TMath::Cos(theta);
+ //if(fDebug==1) printf("\n Momentum in RS of the moving source: p = (%f, %f, %f)\n",q[0],q[1],q[2]);
+
/* Transform to system of the target nucleus */
/* beta is passed as negative, because the gray nucleons are slowed down */
Lorentz(m, -beta, q);
+ //if(fDebug==1) printf(" Momentum in RS of the target nucleus: p = (%f, %f, %f)\n",q[0],q[1],q[2]);
/* Transform to laboratory system */
Lorentz(m, fBeta, q);
q[2] *= fProtonDirection;
+ if(fDebug==1)printf("\n Momentum after LHC boost: p = (%f, %f, %f)\n",q[0],q[1],q[2]);
+
+ if(fBeamCrossingAngle>0.) BeamCrossDivergence(1, q); // applying crossing angle
+ if(fBeamDivergence>0.) BeamCrossDivergence(2, q); // applying divergence
+
}
Double_t AliGenSlowNucleons::Maxwell(Double_t m, Double_t p, Double_t T)
}
+//_____________________________________________________________________________
void AliGenSlowNucleons::Lorentz(Double_t m, Double_t beta, Float_t* q)
{
/* Lorentz transform in the direction of q[2] */
- Double_t gamma = 1/sqrt((1.-beta)*(1.+beta));
- Double_t energy = sqrt(m*m + q[0]*q[0] + q[1]*q[1] + q[2]*q[2]);
+ Double_t gamma = 1./TMath::Sqrt((1.-beta)*(1.+beta));
+ Double_t energy = TMath::Sqrt(m*m + q[0]*q[0] + q[1]*q[1] + q[2]*q[2]);
q[2] = gamma * (q[2] + beta*energy);
+ //printf(" \t beta %1.10f gamma %f energy %f -> p_z = %f\n",beta, gamma, energy,q[2]);
+}
+
+//_____________________________________________________________________________
+void AliGenSlowNucleons::BeamCrossDivergence(Int_t iwhat, Float_t *pLab)
+{
+ // Applying beam divergence and crossing angle
+ //
+ Double_t pmod = TMath::Sqrt(pLab[0]*pLab[0]+pLab[1]*pLab[1]+pLab[2]*pLab[2]);
+
+ Double_t tetdiv = 0.;
+ Double_t fidiv = 0.;
+ if(iwhat==1){
+ tetdiv = fBeamCrossingAngle;
+ fidiv = k2PI/4.;
+ }
+ else if(iwhat==2){
+ tetdiv = fBeamDivEvent;
+ fidiv = (gRandom->Rndm())*k2PI;
+ }
+
+ Double_t tetpart = TMath::ATan2(TMath::Sqrt(pLab[0]*pLab[0]+pLab[1]*pLab[1]), pLab[2]);
+ Double_t fipart=0.;
+ if(TMath::Abs(pLab[1])>0. || TMath::Abs(pLab[0])>0.) fipart = TMath::ATan2(pLab[1], pLab[0]);
+ if(fipart<0.) {fipart = fipart+k2PI;}
+ tetdiv = tetdiv*kRaddeg;
+ fidiv = fidiv*kRaddeg;
+ tetpart = tetpart*kRaddeg;
+ fipart = fipart*kRaddeg;
+
+ Double_t angleSum[2]={0., 0.};
+ AddAngle(tetpart,fipart,tetdiv,fidiv,angleSum);
+
+ Double_t tetsum = angleSum[0];
+ Double_t fisum = angleSum[1];
+ //printf("tetpart %f fipart %f tetdiv %f fidiv %f angleSum %f %f\n",tetpart,fipart,tetdiv,fidiv,angleSum[0],angleSum[1]);
+ tetsum = tetsum*kDegrad;
+ fisum = fisum*kDegrad;
+
+ pLab[0] = pmod*TMath::Sin(tetsum)*TMath::Cos(fisum);
+ pLab[1] = pmod*TMath::Sin(tetsum)*TMath::Sin(fisum);
+ pLab[2] = pmod*TMath::Cos(tetsum);
+ if(fDebug==1){
+ if(iwhat==1) printf(" Beam crossing angle %f mrad ", fBeamCrossingAngle*1000.);
+ else if(iwhat==2) printf(" Beam divergence %f mrad ", fBeamDivEvent*1000.);
+ printf(" p = (%f, %f, %f)\n",pLab[0],pLab[1],pLab[2]);
+ }
+}
+
+//_____________________________________________________________________________
+void AliGenSlowNucleons::AddAngle(Double_t theta1, Double_t phi1,
+ Double_t theta2, Double_t phi2, Double_t *angleSum)
+{
+ // Calculating the sum of 2 angles
+ Double_t temp = -1.;
+ Double_t conv = 180./TMath::ACos(temp);
+
+ Double_t ct1 = TMath::Cos(theta1/conv);
+ Double_t st1 = TMath::Sin(theta1/conv);
+ Double_t cp1 = TMath::Cos(phi1/conv);
+ Double_t sp1 = TMath::Sin(phi1/conv);
+ Double_t ct2 = TMath::Cos(theta2/conv);
+ Double_t st2 = TMath::Sin(theta2/conv);
+ Double_t cp2 = TMath::Cos(phi2/conv);
+ Double_t sp2 = TMath::Sin(phi2/conv);
+ Double_t cx = ct1*cp1*st2*cp2+st1*cp1*ct2-sp1*st2*sp2;
+ Double_t cy = ct1*sp1*st2*cp2+st1*sp1*ct2+cp1*st2*sp2;
+ Double_t cz = ct1*ct2-st1*st2*cp2;
+
+ Double_t rtetsum = TMath::ACos(cz);
+ Double_t tetsum = conv*rtetsum;
+ if(TMath::Abs(tetsum)<1e-4 || tetsum==180.) return;
+
+ temp = cx/TMath::Sin(rtetsum);
+ if(temp>1.) temp=1.;
+ if(temp<-1.) temp=-1.;
+ Double_t fisum = conv*TMath::ACos(temp);
+ if(cy<0) {fisum = 360.-fisum;}
+
+ angleSum[0] = tetsum;
+ angleSum[1] = fisum;
+}
+
+//_____________________________________________________________________________
+void AliGenSlowNucleons::SetProcessID(Int_t nt, UInt_t process)
+{
+ // Tag the particle as
+ // gray or black
+ if (fStack)
+ fStack->Particle(nt)->SetUniqueID(process);
+ else
+ gAlice->GetMCApp()->Particle(nt)->SetUniqueID(process);
}