**************************************************************************/
/* $Id$ */
+//
+// Utility class to make simple Glauber type calculations
+// for SYMMETRIC collision geometries (AA):
+// Impact parameter, production points, reaction plane dependence
+//
+// The SimulateTrigger method can be used for simple MB and hard-process
+// (binary scaling) trigger studies.
+//
+// Some basic quantities can be visualized directly.
+//
+// The default set-up for PbPb or AUAu collisions can be read from a file
+// calling Init(1) or Init(2) if you want to read Almonds too.
+//
+// ***** If you change settings dont forget to call init afterwards, *****
+// ***** in order to update the formulas with the new parameters. *****
+//
+// Author: andreas.morsch@cern.ch
+//=================== Added by A. Dainese 11/02/04 ===========================
+// Calculate path length for a parton with production point (x0,y0)
+// and propagation direction (ux=cos(phi0),uy=sin(phi0))
+// in a collision with impact parameter b and functions that make use
+// of it.
+//=================== Added by A. Dainese 05/03/04 ===========================
+// Calculation of line integrals I0 and I1
+// integral0 = \int_0^ellCut dl*(T_A*T_B)(x0+l*ux,y0+l*uy)
+// integral1 = \int_0^ellCut dl*l*(T_A*T_B)(x0+l*ux,y0+l*uy)
+// mostly for use in the Quenching class
+//=================== Added by C. Loizdes 27/03/04 ===========================
+// Handling of AuAu collisions
+// More get/set functions
+// Comments, units and clearing of code
+//
// from AliRoot
#include "AliFastGlauber.h"
// from root
-#include <TH1F.h>
+#include <TCanvas.h>
#include <TF1.h>
#include <TF2.h>
-#include <TCanvas.h>
-#include <TRandom.h>
#include <TFile.h>
+#include <TH1F.h>
+#include <TH2F.h>
+#include <TLegend.h>
+#include <TMath.h>
+#include <TRandom.h>
+#include <TStyle.h>
ClassImp(AliFastGlauber)
-TF1* AliFastGlauber::fWSb = NULL;
-TF2* AliFastGlauber::fWSbz = NULL;
-TF1* AliFastGlauber::fWSz = NULL;
-TF1* AliFastGlauber::fWSta = NULL;
-TF2* AliFastGlauber::fWStarfi = NULL;
-TF2* AliFastGlauber::fWAlmond = NULL;
-TF1* AliFastGlauber::fWStaa = NULL;
-TF1* AliFastGlauber::fWSgeo = NULL;
-TF1* AliFastGlauber::fWSbinary = NULL;
-TF1* AliFastGlauber::fWSN = NULL;
-TF1* AliFastGlauber::fWPathLength0 = NULL;
-TF1* AliFastGlauber::fWPathLength = NULL;
-TF1* AliFastGlauber::fWEnergyDensity = NULL;
-TF1* AliFastGlauber::fWIntRadius = NULL;
-Float_t AliFastGlauber::fbMax = 0.;
-
-AliFastGlauber::AliFastGlauber()
-{
-// Default Constructor
-//
-// Defaults for Pb
- SetWoodSaxonParameters(6.624, 0.549, 0.00, 7.69e-4);
- SetHardCrossSection();
- SetMaxImpact();
+Float_t AliFastGlauber::fgBMax = 0.;
+TF1* AliFastGlauber::fgWSb = NULL;
+TF1* AliFastGlauber::fgRWSb = NULL;
+TF2* AliFastGlauber::fgWSbz = NULL;
+TF1* AliFastGlauber::fgWSz = NULL;
+TF1* AliFastGlauber::fgWSta = NULL;
+TF2* AliFastGlauber::fgWStarfi = NULL;
+TF2* AliFastGlauber::fgWAlmond = NULL;
+TF1* AliFastGlauber::fgWStaa = NULL;
+TF1* AliFastGlauber::fgWSgeo = NULL;
+TF1* AliFastGlauber::fgWSbinary = NULL;
+TF1* AliFastGlauber::fgWSN = NULL;
+TF1* AliFastGlauber::fgWPathLength0 = NULL;
+TF1* AliFastGlauber::fgWPathLength = NULL;
+TF1* AliFastGlauber::fgWEnergyDensity = NULL;
+TF1* AliFastGlauber::fgWIntRadius = NULL;
+TF2* AliFastGlauber::fgWKParticipants = NULL;
+TF1* AliFastGlauber::fgWParticipants = NULL;
+TF2* AliFastGlauber::fgWAlmondCurrent = NULL;
+TF2* AliFastGlauber::fgWAlmondFixedB[40];
+const Int_t AliFastGlauber::fgkMCInts = 100000;
+AliFastGlauber* AliFastGlauber::fgGlauber = NULL;
+
+
+AliFastGlauber::AliFastGlauber():
+ fWSr0(0.),
+ fWSd(0.),
+ fWSw(0.),
+ fWSn(0.),
+ fSigmaHard(0.),
+ fSigmaNN(0.),
+ fA(0),
+ fBmin(0.),
+ fBmax(0.),
+ fEllDef(0),
+ fName()
+{
+ // Default Constructor
+ // Defaults for Pb
+ SetMaxImpact();
+ SetLengthDefinition();
+ SetPbPbLHC();
+ fXY[0] = fXY[1] = 0;
+ fI0I1[0] = fI0I1[1] = 0;
}
-void AliFastGlauber::Init(Int_t mode)
+AliFastGlauber::AliFastGlauber(const AliFastGlauber & gl)
+ :TObject(gl),
+ fWSr0(0.),
+ fWSd(0.),
+ fWSw(0.),
+ fWSn(0.),
+ fSigmaHard(0.),
+ fSigmaNN(0.),
+ fA(0),
+ fBmin(0.),
+ fBmax(0.),
+ fEllDef(0),
+ fName()
{
-// Initialisation
-//
-// Wood-Saxon
-//
- fWSb = new TF1("WSb", WSb, 0, fbMax, 4);
- fWSb->SetParameter(0, fWSr0);
- fWSb->SetParameter(1, fWSd);
- fWSb->SetParameter(2, fWSw);
- fWSb->SetParameter(3, fWSn);
-
- fWSbz = new TF2("WSbz", WSbz, 0, fbMax, 4);
- fWSbz->SetParameter(0, fWSr0);
- fWSbz->SetParameter(1, fWSd);
- fWSbz->SetParameter(2, fWSw);
- fWSbz->SetParameter(3, fWSn);
-
- fWSz = new TF1("WSz", WSz, 0, fbMax, 5);
- fWSz->SetParameter(0, fWSr0);
- fWSz->SetParameter(1, fWSd);
- fWSz->SetParameter(2, fWSw);
- fWSz->SetParameter(3, fWSn);
+// Copy constructor
+ gl.Copy(*this);
+ fXY[0] = fXY[1] = 0;
+ fI0I1[0] = fI0I1[1] = 0;
+}
-//
-// Thickness
-//
- fWSta = new TF1("WSta", WSta, 0., fbMax, 0);
-
-//
-// Overlap Kernel
-//
- fWStarfi = new TF2("WStarfi", WStarfi, 0., fbMax, 0., TMath::Pi(), 1);
- fWStarfi->SetParameter(0, 0.);
- fWStarfi->SetNpx(200);
- fWStarfi->SetNpy(20);
-//
-// Almond shaped interaction region
-//
- fWAlmond = new TF2("WAlmond", WAlmond, -fbMax, fbMax, -fbMax, fbMax, 1);
- fWAlmond->SetParameter(0, 0.);
- fWAlmond->SetNpx(200);
- fWAlmond->SetNpy(200);
-//
-// Path Length as a function of Phi
-//
- fWPathLength0 = new TF1("WPathLength0", WPathLength0, -TMath::Pi(), TMath::Pi(), 1);
- fWPathLength0->SetParameter(0, 0.);
- fWPathLength = new TF1("WPathLength", WPathLength, -TMath::Pi(), TMath::Pi(), 2);
-// Impact Parameter
- fWPathLength->SetParameter(0, 0.);
-// Number of interactions used for average
- fWPathLength->SetParameter(1, 1000.);
+AliFastGlauber* AliFastGlauber::Instance()
+{
+// Set random number generator
+ if (fgGlauber) {
+ return fgGlauber;
+ } else {
+ fgGlauber = new AliFastGlauber();
+ return fgGlauber;
+ }
+}
- fWIntRadius = new TF1("WIntRadius", WIntRadius, 0., fbMax, 1);
- fWIntRadius->SetParameter(0, 0.);
+AliFastGlauber::~AliFastGlauber()
+{
+// Destructor
+ for(Int_t k=0; k<40; k++) delete fgWAlmondFixedB[k];
+}
+void AliFastGlauber::SetAuAuRhic()
+{
+ //Set all parameters for RHIC
+ SetWoodSaxonParametersAu();
+ SetHardCrossSection();
+ SetNNCrossSection(42);
+ SetNucleus(197);
+ SetFileName("$(ALICE_ROOT)/FASTSIM/data/glauberAuAu.root");
+}
-//
-// Overlap
-//
- if (! mode) {
- fWStaa = new TF1("WStaa", WStaa, 0., fbMax, 0);
- fWStaa->SetNpx(100);
- } else {
- TFile* f = new TFile("$(ALICE_ROOT)/FASTSIM/data/glauberPbPb.root");
- fWStaa = (TF1*) f->Get("WStaa");
- }
+void AliFastGlauber::SetPbPbLHC()
+{
+ //Set all parameters for LHC
+ SetWoodSaxonParametersPb();
+ SetHardCrossSection();
+ SetNNCrossSection();
+ SetNucleus();
+ SetFileName();
+}
+
+void AliFastGlauber::Init(Int_t mode)
+{
+ // Initialisation
+ // mode = 0; all functions are calculated
+ // mode = 1; overlap function is read from file (for Pb-Pb only)
+ // mode = 2; interaction almond functions are read from file
+ // USE THIS FOR PATH LENGTH CALC.!
+ //
+
+ //
+ Reset();
+ //
+
+ //
+ // Wood-Saxon
+ //
+ fgWSb = new TF1("WSb", WSb, 0, fgBMax, 4);
+ fgWSb->SetParameter(0, fWSr0);
+ fgWSb->SetParameter(1, fWSd);
+ fgWSb->SetParameter(2, fWSw);
+ fgWSb->SetParameter(3, fWSn);
+
+ fgRWSb = new TF1("RWSb", RWSb, 0, fgBMax, 4);
+ fgRWSb->SetParameter(0, fWSr0);
+ fgRWSb->SetParameter(1, fWSd);
+ fgRWSb->SetParameter(2, fWSw);
+ fgRWSb->SetParameter(3, fWSn);
+
+ fgWSbz = new TF2("WSbz", WSbz, 0, fgBMax, 0, fgBMax, 4);
+ fgWSbz->SetParameter(0, fWSr0);
+ fgWSbz->SetParameter(1, fWSd);
+ fgWSbz->SetParameter(2, fWSw);
+ fgWSbz->SetParameter(3, fWSn);
+
+ fgWSz = new TF1("WSz", WSz, 0, fgBMax, 5);
+ fgWSz->SetParameter(0, fWSr0);
+ fgWSz->SetParameter(1, fWSd);
+ fgWSz->SetParameter(2, fWSw);
+ fgWSz->SetParameter(3, fWSn);
+
+ //
+ // Thickness
+ //
+ fgWSta = new TF1("WSta", WSta, 0., fgBMax, 0);
-//
- fWEnergyDensity = new TF1("WEnergyDensity", WEnergyDensity, 0., 2. * fWSr0, 1);
- fWEnergyDensity->SetParameter(0, fWSr0 + 1.);
+ //
+ // Overlap Kernel
+ //
+ fgWStarfi = new TF2("WStarfi", WStarfi, 0., fgBMax, 0., TMath::Pi(), 1);
+ fgWStarfi->SetParameter(0, 0.);
+ fgWStarfi->SetNpx(200);
+ fgWStarfi->SetNpy(20);
+
+ //
+ // Participants Kernel
+ //
+ fgWKParticipants = new TF2("WKParticipants", WKParticipants, 0., fgBMax, 0., TMath::Pi(), 3);
+ fgWKParticipants->SetParameter(0, 0.);
+ fgWKParticipants->SetParameter(1, fSigmaNN);
+ fgWKParticipants->SetParameter(2, fA);
+ fgWKParticipants->SetNpx(200);
+ fgWKParticipants->SetNpy(20);
+
+ //
+ // Overlap and Participants
+ //
+ if (!mode) {
+ fgWStaa = new TF1("WStaa", WStaa, 0., fgBMax, 1);
+ fgWStaa->SetNpx(100);
+ fgWStaa->SetParameter(0,fA);
+ fgWStaa->SetNpx(100);
+ fgWParticipants = new TF1("WParticipants", WParticipants, 0., fgBMax, 2);
+ fgWParticipants->SetParameter(0, fSigmaNN);
+ fgWParticipants->SetParameter(1, fA);
+ fgWParticipants->SetNpx(100);
+ } else {
+ Info("Init","Reading overlap function from file %s",fName.Data());
+ TFile* f = new TFile(fName.Data());
+ if(!f->IsOpen()){
+ Fatal("Init", "Could not open file %s",fName.Data());
+ }
+ fgWStaa = (TF1*) f->Get("WStaa");
+ fgWParticipants = (TF1*) f->Get("WParticipants");
+ delete f;
+ }
+
+ //
+ // Energy Density
+ //
+ fgWEnergyDensity = new TF1("WEnergyDensity", WEnergyDensity, 0., 2. * fWSr0, 1);
+ fgWEnergyDensity->SetParameter(0, fWSr0 + 1.);
-//
-// Geometrical Cross-Section
-//
- fWSgeo = new TF1("WSgeo", WSgeo, 0., fbMax, 0);
- fWSgeo->SetNpx(100);
-//
-// Hard cross section (~ binary collisions)
-//
- fWSbinary = new TF1("WSbinary", WSbinary, 0., fbMax, 1);
- fWSbinary->SetParameter(0, fSigmaHard); // mb
- fWSbinary->SetNpx(100);
-//
-// Hard collisions per event
-//
- fWSN = new TF1("WSN", WSN, 0., fbMax, 1);
- fWSN->SetNpx(100);
+ //
+ // Geometrical Cross-Section
+ //
+ fgWSgeo = new TF1("WSgeo", WSgeo, 0., fgBMax, 1);
+ fgWSgeo->SetParameter(0,fSigmaNN); //mbarn
+ fgWSgeo->SetNpx(100);
+
+ //
+ // Hard cross section (binary collisions)
+ //
+ fgWSbinary = new TF1("WSbinary", WSbinary, 0., fgBMax, 1);
+ fgWSbinary->SetParameter(0, fSigmaHard); //mbarn
+ fgWSbinary->SetNpx(100);
+
+ //
+ // Hard collisions per event
+ //
+ fgWSN = new TF1("WSN", WSN, 0.01, fgBMax, 1);
+ fgWSN->SetNpx(100);
+
+ //
+ // Almond shaped interaction region
+ //
+ fgWAlmond = new TF2("WAlmond", WAlmond, -fgBMax, fgBMax, -fgBMax, fgBMax, 1);
+ fgWAlmond->SetParameter(0, 0.);
+ fgWAlmond->SetNpx(200);
+ fgWAlmond->SetNpy(200);
+
+ if(mode==2) {
+ Info("Init","Reading interaction almonds from file: %s",fName.Data());
+ Char_t almondName[100];
+ TFile* ff = new TFile(fName.Data());
+ for(Int_t k=0; k<40; k++) {
+ snprintf(almondName,100, "WAlmondFixedB%d",k);
+ fgWAlmondCurrent = (TF2*)ff->Get(almondName);
+ fgWAlmondFixedB[k] = fgWAlmondCurrent;
+ }
+ delete ff;
+ }
+
+ fgWIntRadius = new TF1("WIntRadius", WIntRadius, 0., fgBMax, 1);
+ fgWIntRadius->SetParameter(0, 0.);
+
+ //
+ // Path Length as a function of Phi
+ //
+ fgWPathLength0 = new TF1("WPathLength0", WPathLength0, -TMath::Pi(), TMath::Pi(), 2);
+ fgWPathLength0->SetParameter(0, 0.);
+ fgWPathLength0->SetParameter(1, 0.); //Pathlength definition
+
+ fgWPathLength = new TF1("WPathLength", WPathLength, -TMath::Pi(), TMath::Pi(), 3);
+ fgWPathLength->SetParameter(0, 0.); //Impact Parameter
+ fgWPathLength->SetParameter(1, 1000.); //Number of interactions used for average
+ fgWPathLength->SetParameter(2, 0); //Pathlength definition
}
-void AliFastGlauber::DrawWSb()
+void AliFastGlauber::Reset() const
{
-//
-// Draw Wood-Saxon Nuclear Density Function
-//
- TCanvas *c1 = new TCanvas("c1","Wood Saxon",400,10,600,700);
- c1->cd();
- fWSb->Draw();
+ //
+ // Reset dynamic allocated formulas
+ // in case init is called twice
+
+ if(fgWSb) delete fgWSb;
+ if(fgRWSb) delete fgRWSb;
+ if(fgWSbz) delete fgWSbz;
+ if(fgWSz) delete fgWSz;
+ if(fgWSta) delete fgWSta;
+ if(fgWStarfi) delete fgWStarfi;
+ if(fgWAlmond) delete fgWAlmond;
+ if(fgWStaa) delete fgWStaa;
+ if(fgWSgeo) delete fgWSgeo;
+ if(fgWSbinary) delete fgWSbinary;
+ if(fgWSN) delete fgWSN;
+ if(fgWPathLength0) delete fgWPathLength0;
+ if(fgWPathLength) delete fgWPathLength;
+ if(fgWEnergyDensity) delete fgWEnergyDensity;
+ if(fgWIntRadius) delete fgWIntRadius;
+ if(fgWKParticipants) delete fgWKParticipants;
+ if(fgWParticipants) delete fgWParticipants;
}
-void AliFastGlauber::DrawOverlap()
+void AliFastGlauber::DrawWSb() const
{
-//
-// Draw Overlap Function
-//
- TCanvas *c2 = new TCanvas("c2","Overlap",400,10,600,700);
- c2->cd();
- fWStaa->Draw();
+ //
+ // Draw Wood-Saxon Nuclear Density Function
+ //
+ TCanvas *c1 = new TCanvas("c1","Wood Saxon",400,10,600,700);
+ c1->cd();
+ Double_t max=fgWSb->GetMaximum(0.,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fwsb","Wood Saxon: #rho(r) = n (1-#omega(r/r_{0})^2)/(1+exp((r-r_{0})/d)) [fm^{-3}]",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("r [fm]");
+ h2f->GetYaxis()->SetNoExponent(kTRUE);
+ h2f->GetYaxis()->SetTitle("#rho [fm^{-3}]");
+ h2f->Draw();
+ fgWSb->Draw("same");
+ TLegend *l1a = new TLegend(0.45,0.6,.90,0.8);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label,100, "r_{0} = %.2f fm",fWSr0);
+ l1a->AddEntry(fgWSb,label,"");
+ snprintf(label,100, "d = %.2f fm",fWSd);
+ l1a->AddEntry(fgWSb,label,"");
+ snprintf(label,100, "n = %.2e fm^{-3}",fWSn);
+ l1a->AddEntry(fgWSb,label,"");
+ snprintf(label,100, "#omega = %.2f",fWSw);
+ l1a->AddEntry(fgWSb,label,"");
+ l1a->Draw();
+ c1->Update();
}
-void AliFastGlauber::DrawThickness()
+void AliFastGlauber::DrawOverlap() const
{
-//
-// Draw Thickness Function
-//
- TCanvas *c3 = new TCanvas("c3","Thickness",400,10,600,700);
- c3->cd();
- fWSta->Draw();
+ //
+ // Draw Overlap Function
+ //
+ TCanvas *c2 = new TCanvas("c2","Overlap",400,10,600,700);
+ c2->cd();
+ Double_t max=fgWStaa->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2ftaa","Overlap function: T_{AB} [mbarn^{-1}]",2,0,fgBMax,2,0, max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("T_{AB} [mbarn^{-1}]");
+ h2f->Draw();
+ fgWStaa->Draw("same");
}
-void AliFastGlauber::DrawGeo()
+void AliFastGlauber::DrawParticipants() const
{
-//
-// Draw Geometrical Cross-Section
-//
- TCanvas *c3 = new TCanvas("c3","Geometrical Cross-Section",400,10,600,700);
- c3->cd();
- fWSgeo->Draw();
+ //
+ // Draw Number of Participants Npart
+ //
+ TCanvas *c3 = new TCanvas("c3","Participants",400,10,600,700);
+ c3->cd();
+ Double_t max=fgWParticipants->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fpart","Number of Participants",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("N_{part}");
+ h2f->Draw();
+ fgWParticipants->Draw("same");
+ TLegend *l1a = new TLegend(0.50,0.75,.90,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label,100, "#sigma^{inel.}_{NN} = %.1f mbarn",fSigmaNN);
+ l1a->AddEntry(fgWParticipants,label,"");
+ l1a->Draw();
+ c3->Update();
}
-void AliFastGlauber::DrawBinary()
+void AliFastGlauber::DrawThickness() const
{
-//
-// Draw Wood-Saxon Nuclear Density Function
-//
- TCanvas *c4 = new TCanvas("c4","Binary Cross-Section",400,10,600,700);
- c4->cd();
- fWSbinary->Draw();
+ //
+ // Draw Thickness Function
+ //
+ TCanvas *c4 = new TCanvas("c4","Thickness",400,10,600,700);
+ c4->cd();
+ Double_t max=fgWSta->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fta","Thickness function: T_{A} [fm^{-2}]",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("T_{A} [fm^{-2}]");
+ h2f->Draw();
+ fgWSta->Draw("same");
}
-void AliFastGlauber::DrawN()
+void AliFastGlauber::DrawGeo() const
{
-//
-// Draw Binaries per event
-//
- TCanvas *c5 = new TCanvas("c5","Binaries per event",400,10,600,700);
- c5->cd();
- fWSN->Draw();
+ //
+ // Draw Geometrical Cross-Section
+ //
+ TCanvas *c5 = new TCanvas("c5","Geometrical Cross-Section",400,10,600,700);
+ c5->cd();
+ Double_t max=fgWSgeo->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fgeo","Differential Geometrical Cross-Section: d#sigma^{geo}_{AB}/db [fm]",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("d#sigma^{geo}_{AB}/db [fm]");
+ h2f->Draw();
+ fgWSgeo->Draw("same");
+ TLegend *l1a = new TLegend(0.10,0.8,.40,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label,100, "#sigma_{NN}^{inel.} = %.1f mbarn",fSigmaNN);
+ l1a->AddEntry(fgWSgeo,label,"");
+ l1a->Draw();
+ c5->Update();
}
-void AliFastGlauber::DrawKernel(Double_t b)
+void AliFastGlauber::DrawBinary() const
{
-//
-// Draw Kernel
-//
- TCanvas *c6 = new TCanvas("c6","Kernel",400,10,600,700);
- c6->cd();
- fWStarfi->SetParameter(0, b);
- fWStarfi->Draw();
+ //
+ // Draw Binary Cross-Section
+ //
+ TCanvas *c6 = new TCanvas("c6","Binary Cross-Section",400,10,600,700);
+ c6->cd();
+ Double_t max=fgWSbinary->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fbinary","Differential Binary Cross-Section: #sigma^{hard}_{NN} dT_{AB}/db [fm]",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("d#sigma^{hard}_{AB}/db [fm]");
+ h2f->Draw();
+ fgWSbinary->Draw("same");
+ TLegend *l1a = new TLegend(0.50,0.8,.90,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label,100, "#sigma_{NN}^{hard} = %.1f mbarn",fSigmaHard);
+ l1a->AddEntry(fgWSb,label,"");
+ l1a->Draw();
+ c6->Update();
}
-void AliFastGlauber::DrawAlmond(Double_t b)
+void AliFastGlauber::DrawN() const
{
-//
-// Draw Interaction Almond
-//
- TCanvas *c7 = new TCanvas("c7","Almond",400,10,600,700);
- c7->cd();
- fWAlmond->SetParameter(0, b);
- fWAlmond->Draw();
+ //
+ // Draw Binaries per event (Ncoll)
+ //
+ TCanvas *c7 = new TCanvas("c7","Binaries per event",400,10,600,700);
+ c7->cd();
+ Double_t max=fgWSN->GetMaximum(0.01,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fhardcols","Number of hard collisions: T_{AB} #sigma^{hard}_{NN}/#sigma_{AB}^{geo}",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("N_{coll}");
+ h2f->Draw();
+ fgWSN->Draw("same");
+ TLegend *l1a = new TLegend(0.50,0.75,.90,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label,100, "#sigma^{hard}_{NN} = %.1f mbarn",fSigmaHard);
+ l1a->AddEntry(fgWSN,label,"");
+ snprintf(label,100, "#sigma^{inel.}_{NN} = %.1f mbarn",fSigmaNN);
+ l1a->AddEntry(fgWSN,label,"");
+ l1a->Draw();
+ c7->Update();
}
-void AliFastGlauber::DrawPathLength0(Double_t b)
+void AliFastGlauber::DrawKernel(Double_t b) const
{
-//
-// Draw Path Length
-//
- TCanvas *c8 = new TCanvas("c8","Path Length",400,10,600,700);
- c8->cd();
- fWPathLength0->SetParameter(0, b);
- fWPathLength0->SetMinimum(0.);
- fWPathLength0->SetMaximum(10.);
- fWPathLength0->Draw();
+ //
+ // Draw Kernel
+ //
+ TCanvas *c8 = new TCanvas("c8","Kernel",400,10,600,700);
+ c8->cd();
+ fgWStarfi->SetParameter(0, b);
+ TH2F *h2f=new TH2F("h2fkernel","Kernel of Overlap function: d^{2}T_{AB}/dr/d#phi [fm^{-3}]",2,0,fgBMax,2,0,TMath::Pi());
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("r [fm]");
+ h2f->GetYaxis()->SetTitle("#phi [rad]");
+ h2f->Draw();
+ fgWStarfi->Draw("same");
+ TLegend *l1a = new TLegend(0.65,0.8,.90,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label, 100, "b = %.1f fm",b);
+ l1a->AddEntry(fgWStarfi,label,"");
+ l1a->Draw();
+ c8->Update();
}
-void AliFastGlauber::DrawPathLength(Double_t b , Int_t ni)
+void AliFastGlauber::DrawAlmond(Double_t b) const
{
-//
-// Draw Path Length
-//
- TCanvas *c9 = new TCanvas("c9","Path Length",400,10,600,700);
- c9->cd();
- fWAlmond->SetParameter(0, b);
+ //
+ // Draw Interaction Almond
+ //
+ TCanvas *c9 = new TCanvas("c9","Almond",400,10,600,700);
+ c9->cd();
+ fgWAlmond->SetParameter(0, b);
+ TH2F *h2f=new TH2F("h2falmond","Interaction Almond [fm^{-4}]",2,-fgBMax, fgBMax, 2, -fgBMax, fgBMax);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("x [fm]");
+ h2f->GetYaxis()->SetTitle("y [fm]");
+ h2f->Draw("");
+ gStyle->SetPalette(1);
+ fgWAlmond->Draw("colzsame");
+ TLegend *l1a = new TLegend(0.65,0.8,.90,0.9);
+ l1a->SetFillStyle(0);
+ l1a->SetBorderSize(0);
+ Char_t label[100];
+ snprintf(label, 100, "b = %.1f fm",b);
+ l1a->AddEntry(fgWAlmond,label,"");
+ l1a->Draw();
+ c9->Update();
+}
- fWPathLength->SetParameter(0, b);
- fWPathLength->SetParameter(1, Double_t (ni));
- fWPathLength->SetMinimum(0.);
- fWPathLength->SetMaximum(10.);
- fWPathLength->Draw();
+void AliFastGlauber::DrawEnergyDensity() const
+{
+ //
+ // Draw energy density
+ //
+ TCanvas *c10 = new TCanvas("c10","Energy Density",400, 10, 600, 700);
+ c10->cd();
+ fgWEnergyDensity->SetMinimum(0.);
+ Double_t max=fgWEnergyDensity->GetMaximum(0,fgWEnergyDensity->GetParameter(0))*1.01;
+ TH2F *h2f=new TH2F("h2fenergydens","Energy density",2,0,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("b [fm]");
+ h2f->GetYaxis()->SetTitle("fm^{-4}");
+ h2f->Draw();
+ fgWEnergyDensity->Draw("same");
+ c10->Update();
}
-void AliFastGlauber::DrawIntRadius(Double_t b)
+void AliFastGlauber::DrawPathLength0(Double_t b, Int_t iopt) const
{
-//
-// Draw Interaction Radius
-//
- TCanvas *c10 = new TCanvas("c10","Interaction Radius",400,10,600,700);
- c10->cd();
- fWIntRadius->SetParameter(0, b);
- fWIntRadius->SetMinimum(0.);
- fWIntRadius->Draw();
+ //
+ // Draw Path Length
+ //
+ TCanvas *c11 = new TCanvas("c11","Path Length",400,10,600,700);
+ c11->cd();
+ fgWPathLength0->SetParameter(0, b);
+ fgWPathLength0->SetParameter(1, Double_t(iopt));
+ fgWPathLength0->SetMinimum(0.);
+ fgWPathLength0->SetMaximum(10.);
+ TH2F *h2f=new TH2F("h2fpathlength0","Path length",2,-TMath::Pi(), TMath::Pi(),2,0,10.);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("#phi [rad]");
+ h2f->GetYaxis()->SetTitle("l [fm]");
+ h2f->Draw();
+ fgWPathLength0->Draw("same");
}
-void AliFastGlauber::DrawEnergyDensity()
+void AliFastGlauber::DrawPathLength(Double_t b , Int_t ni, Int_t iopt) const
{
-//
-// Draw energy density
-//
- TCanvas *c11 = new TCanvas("c11","Energy Density",400, 10, 600, 700);
- c11->cd();
- fWEnergyDensity->SetMinimum(0.);
- fWEnergyDensity->Draw();
+ //
+ // Draw Path Length
+ //
+ TCanvas *c12 = new TCanvas("c12","Path Length",400,10,600,700);
+ c12->cd();
+ fgWAlmond->SetParameter(0, b);
+ fgWPathLength->SetParameter(0, b);
+ fgWPathLength->SetParameter(1, Double_t (ni));
+ fgWPathLength->SetParameter(2, Double_t (iopt));
+ fgWPathLength->SetMinimum(0.);
+ fgWPathLength->SetMaximum(10.);
+ TH2F *h2f=new TH2F("h2fpathlength","Path length",2,-TMath::Pi(), TMath::Pi(),2,0,10.);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("#phi [rad]");
+ h2f->GetYaxis()->SetTitle("l [fm]");
+ h2f->Draw();
+ fgWPathLength->Draw("same");
}
-Double_t AliFastGlauber::WSb(Double_t* x, Double_t* par)
+void AliFastGlauber::DrawIntRadius(Double_t b) const
{
-//
-// Woods-Saxon Parameterisation
-// as a function of radius
-//
- Double_t xx = x[0];
- Double_t r0 = par[0];
- Double_t d = par[1];
- Double_t w = par[2];
- Double_t n = par[3];
-
- Double_t y = n * (1.+w*(xx/r0)*(xx/r0))/(1.+TMath::Exp((xx-r0)/d));
+ //
+ // Draw Interaction Radius
+ //
+ TCanvas *c13 = new TCanvas("c13","Interaction Radius",400,10,600,700);
+ c13->cd();
+ fgWIntRadius->SetParameter(0, b);
+ fgWIntRadius->SetMinimum(0);
+ Double_t max=fgWIntRadius->GetMaximum(0,fgBMax)*1.01;
+ TH2F *h2f=new TH2F("h2fintradius","Interaction Density",2,0.,fgBMax,2,0,max);
+ h2f->SetStats(0);
+ h2f->GetXaxis()->SetTitle("r [fm]");
+ h2f->GetYaxis()->SetTitle("[fm^{-3}]");
+ h2f->Draw();
+ fgWIntRadius->Draw("same");
+}
- return y;
+Double_t AliFastGlauber::WSb(const Double_t* x, const Double_t* par)
+{
+ //
+ // Woods-Saxon Parameterisation
+ // as a function of radius (xx)
+ //
+ const Double_t kxx = x[0]; //fm
+ const Double_t kr0 = par[0]; //fm
+ const Double_t kd = par[1]; //fm
+ const Double_t kw = par[2]; //no units
+ const Double_t kn = par[3]; //fm^-3 (used to normalize integral to one)
+ Double_t y = kn * (1.+kw*(kxx/kr0)*(kxx/kr0))/(1.+TMath::Exp((kxx-kr0)/kd));
+ return y; //fm^-3
}
-Double_t AliFastGlauber::WSbz(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::RWSb(const Double_t* x, const Double_t* par)
{
-//
-// Wood Saxon Parameterisation
-// as a function of z and b
-//
- Double_t bb = x[0];
- Double_t zz = x[1];
- Double_t r0 = par[0];
- Double_t d = par[1];
- Double_t w = par[2];
- Double_t n = par[3];
- Double_t xx = TMath::Sqrt(bb*bb+zz*zz);
- Double_t y = n * (1.+w*(xx/r0)*(xx/r0))/(1.+TMath::Exp((xx-r0)/d));
+ //
+ // Woods-Saxon Parameterisation
+ // as a function of radius (xx)
+ // times r**2
+ const Double_t kxx = x[0]; //fm
+ const Double_t kr0 = par[0]; //fm
+ const Double_t kd = par[1]; //fm
+ const Double_t kw = par[2]; //no units
+ const Double_t kn = par[3]; //fm^-3 (used to normalize integral to one)
+ Double_t y = kxx * kxx * kn * (1.+kw*(kxx/kr0)*(kxx/kr0))/(1.+TMath::Exp((kxx-kr0)/kd));
+
+ return y; //fm^-1
+}
- return y;
+Double_t AliFastGlauber::WSbz(const Double_t* x, const Double_t* par)
+{
+ //
+ // Wood Saxon Parameterisation
+ // as a function of z and b
+ //
+ const Double_t kbb = x[0]; //fm
+ const Double_t kzz = x[1]; //fm
+ const Double_t kr0 = par[0]; //fm
+ const Double_t kd = par[1]; //fm
+ const Double_t kw = par[2]; //no units
+ const Double_t kn = par[3]; //fm^-3 (used to normalize integral to one)
+ const Double_t kxx = TMath::Sqrt(kbb*kbb+kzz*kzz);
+ Double_t y = kn * (1.+kw*(kxx/kr0)*(kxx/kr0))/(1.+TMath::Exp((kxx-kr0)/kd));
+ return y; //fm^-3
}
-Double_t AliFastGlauber::WSz(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::WSz(const Double_t* x, const Double_t* par)
{
-//
-// Wood Saxon Parameterisation
-// as a function of z for fixed b
-//
- Double_t bb = par[4];
- Double_t zz = x[0];
- Double_t r0 = par[0];
- Double_t d = par[1];
- Double_t w = par[2];
- Double_t n = par[3];
- Double_t xx = TMath::Sqrt(bb*bb+zz*zz);
- Double_t y = n * (1.+w*(xx/r0)*(xx/r0))/(1.+TMath::Exp((xx-r0)/d));
+ //
+ // Wood Saxon Parameterisation
+ // as a function of z for fixed b
+ //
+ const Double_t kzz = x[0]; //fm
+ const Double_t kr0 = par[0]; //fm
+ const Double_t kd = par[1]; //fm
+ const Double_t kw = par[2]; //no units
+ const Double_t kn = par[3]; //fm^-3 (used to normalize integral to one)
+ const Double_t kbb = par[4]; //fm
+ const Double_t kxx = TMath::Sqrt(kbb*kbb+kzz*kzz);
+ Double_t y = kn * (1.+kw*(kxx/kr0)*(kxx/kr0))/(1.+TMath::Exp((kxx-kr0)/kd));
+ return y; //fm^-3
+}
- return y;
+Double_t AliFastGlauber::WSta(const Double_t* x, const Double_t* /*par*/)
+{
+ //
+ // Thickness function T_A
+ // as a function of b
+ //
+ const Double_t kb = x[0];
+ fgWSz->SetParameter(4, kb);
+ Double_t y = 2. * fgWSz->Integral(0., fgBMax);
+ return y; //fm^-2
}
-Double_t AliFastGlauber::WSta(Double_t* x, Double_t* /*par*/)
+Double_t AliFastGlauber::WStarfi(const Double_t* x, const Double_t* par)
{
-//
-// Thickness function
-//
- Double_t b = x[0];
- fWSz->SetParameter(4, b);
- Double_t y = 2. * fWSz->Integral(0., fbMax);
- return y;
+ //
+ // Kernel for overlap function: T_A(s)*T_A(s-b)
+ // as a function of r and phi
+ const Double_t kr1 = x[0];
+ const Double_t kphi = x[1];
+ const Double_t kb = par[0];
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + kb*kb - 2.*kr1*kb*TMath::Cos(kphi));
+ Double_t y = kr1 * fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+ return y; //fm^-3
}
+Double_t AliFastGlauber::WStaa(const Double_t* x, const Double_t* par)
+{
+ //
+ // Overlap function
+ // T_{AB}=Int d2s T_A(s)*T_B(s-b)
+ // as a function of b
+ // (normalized to fA*fB)
+ //
+ const Double_t kb = x[0];
+ const Double_t ka = par[0];
+ fgWStarfi->SetParameter(0, kb);
+
+ // root integration seems to fail
+ /*
+ Double_t al[2];
+ Double_t bl[2];
+ al[0] = 1e-6;
+ al[1] = fgBMax;
+ bl[0] = 0.;
+ bl[1] = TMath::Pi();
+ Double_t err;
+
+ Double_t y = 2. * 208. * 208. * fgWStarfi->IntegralMultiple(2, al, bl, 0.001, err);
+ printf("WStaa: %.5e %.5e %.5e\n", b, y, err);
+ */
+
+ //
+ // MC Integration
+ //
+ Double_t y = 0;
+
+
+ for (Int_t i = 0; i < fgkMCInts; i++)
+ {
+
+ const Double_t kphi = TMath::Pi() * gRandom->Rndm();
+ const Double_t kb1 = fgBMax * gRandom->Rndm();
+ y += fgWStarfi->Eval(kb1, kphi);
+ }
+ y *= 2. * TMath::Pi() * fgBMax / fgkMCInts; //fm^-2
+ y *= ka * ka * 0.1; //mbarn^-1
+ return y;
+}
+Double_t AliFastGlauber::WKParticipants(const Double_t* x, const Double_t* par)
+{
+ //
+ // Kernel for number of participants
+ // as a function of r and phi
+ //
+ const Double_t kr1 = x[0];
+ const Double_t kphi = x[1];
+ const Double_t kb = par[0]; //fm
+ const Double_t ksig = par[1]; //mbarn
+ const Double_t ka = par[2]; //mass number
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 +kb*kb - 2.*kr1*kb*TMath::Cos(kphi));
+ const Double_t kxsi = fgWSta->Eval(kr2) * ksig * 0.1; //no units
+ /*
+ Double_t y=(1-TMath::Power((1-xsi),aa))
+ */
+ Double_t a = ka;
+ Double_t sum = ka * kxsi;
+ Double_t y = sum;
+ for (Int_t i = 1; i <= ka; i++)
+ {
+ a--;
+ sum *= (-kxsi) * a / Float_t(i+1);
+ y += sum;
+ }
+ y *= kr1 * fgWSta->Eval(kr1);
+ return y; //fm^-1
+}
-Double_t AliFastGlauber::WStarfi(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::WParticipants(const Double_t* x, const Double_t* par)
{
-//
-// Kernel for overlap function
-//
- Double_t b = par[0];
- Double_t r1 = x[0];
- Double_t phi = x[1];
- Double_t r2 = TMath::Sqrt(r1 * r1 + b * b - 2. * r1 * b * TMath::Cos(phi));
- Double_t y = r1 * fWSta->Eval(r1) * fWSta->Eval(r2);
- return y;
+ //
+ // Number of Participants as
+ // a function of b
+ //
+ const Double_t kb = x[0];
+ const Double_t ksig = par[0]; //mbarn
+ const Double_t ka = par[1]; //mass number
+ fgWKParticipants->SetParameter(0, kb);
+ fgWKParticipants->SetParameter(1, ksig);
+ fgWKParticipants->SetParameter(2, ka);
+
+ //
+ // MC Integration
+ //
+ Double_t y = 0;
+ for (Int_t i = 0; i < fgkMCInts; i++)
+ {
+ const Double_t kphi = TMath::Pi() * gRandom->Rndm();
+ const Double_t kb1 = fgBMax * gRandom->Rndm();
+ y += fgWKParticipants->Eval(kb1, kphi);
+ }
+ y *= 2. * ka * 2. * TMath::Pi() * fgBMax / fgkMCInts;
+ return y; //no units
}
+Double_t AliFastGlauber::WSgeo(const Double_t* x, const Double_t* par)
+{
+ //
+ // Geometrical Cross-Section
+ // as a function of b
+ //
+ const Double_t kb = x[0]; //fm
+ const Double_t ksigNN = par[0]; //mbarn
+ const Double_t ktaa = fgWStaa->Eval(kb); //mbarn^-1
+ Double_t y = 2. * TMath::Pi() * kb * (1. - TMath::Exp(- ksigNN * ktaa));
+ return y; //fm
+}
-Double_t AliFastGlauber::WAlmond(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::WSbinary(const Double_t* x, const Double_t* par)
{
-//
-// Almond shaped interaction region
-//
- Double_t b = par[0];
- Double_t xx = x[0] + b/2.;
- Double_t yy = x[1];
- Double_t r1 = TMath::Sqrt(xx * xx + yy * yy);
- Double_t phi = TMath::ATan2(yy,xx);
-
- Double_t r2 = TMath::Sqrt(r1 * r1 + b * b - 2. * r1 * b * TMath::Cos(phi));
-//
-// Interaction probability calculated as product of thicknesses
-//
- Double_t y = fWSta->Eval(r1) * fWSta->Eval(r2);
- return y;
+ //
+ // Number of binary hard collisions
+ // as a function of b
+ //
+ const Double_t kb = x[0]; //fm
+ const Double_t ksig = par[0]; //mbarn
+ const Double_t ktaa = fgWStaa->Eval(kb); //mbarn^-1
+ Double_t y = 2. * TMath::Pi() * kb * ksig * ktaa;
+ return y; //fm
}
-Double_t AliFastGlauber::WIntRadius(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::WSN(const Double_t* x, const Double_t* /*par*/)
{
-//
-// Average radius at which interaction takes place
-//
-// Radius in the Almond
- Double_t r = x[0];
-// Impact parameter
- Double_t b = par[0];
- fWAlmond->SetParameter(0, b);
-// Steps in phi
- Double_t dphi = 2. * TMath::Pi() / 100.;
-// Average over phi
- Double_t phi = 0.;
- Double_t y = 0.;
-
- for (Int_t i = 0; i < 100; i++) {
- Double_t xx = r * TMath::Cos(phi);
- Double_t yy = r * TMath::Sin(phi);
- y += fWAlmond->Eval(xx,yy);
- phi += dphi;
- } // phi loop
-// Result multiplied by Jacobian (2 pi r)
- return (2. * TMath::Pi() * y * r / 100.);
-}
-
-Double_t AliFastGlauber::WPathLength0(Double_t* x, Double_t* par)
+ //
+ // Number of hard processes per event
+ // as a function of b
+ const Double_t kb = x[0];
+ Double_t y = fgWSbinary->Eval(kb)/fgWSgeo->Eval(kb);
+ return y; //no units
+}
+
+Double_t AliFastGlauber::WEnergyDensity(const Double_t* x, const Double_t* par)
{
-//
-// Path Length as a function of phi for interaction point fixed at (0,0)
-//
-//
-// Steps in r
- const Int_t np = 100;
- const Double_t dr = fbMax/Double_t(np);
-// Impact parameter
- Double_t b = par[0];
-// Phi direction in Almond
- Double_t phi0 = x[0];
- Double_t r = 0.;
+ //
+ // Initial energy density
+ // as a function of the impact parameter
+ //
+ const Double_t kb = x[0];
+ const Double_t krA = par[0];
+ //
+ // Attention: area of transverse reaction zone in hard-sphere approximation !
+ const Double_t krA2=krA*krA;
+ const Double_t kb2=kb*kb;
+ const Double_t ksaa = (TMath::Pi() - 2. * TMath::ASin(kb/ 2./ krA)) * krA2
+ - kb * TMath::Sqrt(krA2 - kb2/ 4.); //fm^2
+ const Double_t ktaa = fgWStaa->Eval(kb); //mbarn^-1
+ Double_t y=ktaa/ksaa*10;
+ return y; //fm^-4
+}
+
+Double_t AliFastGlauber::WAlmond(const Double_t* x, const Double_t* par)
+{
+ //
+ // Almond shaped interaction region
+ // as a function of cartesian x,y.
+ //
+ const Double_t kb = par[0];
+ const Double_t kxx = x[0] + kb/2.;
+ const Double_t kyy = x[1];
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ const Double_t kphi = TMath::ATan2(kyy,kxx);
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + kb*kb - 2.*kr1*kb*TMath::Cos(kphi));
+ //
+ // Interaction probability calculated as product of thicknesses
+ //
+ Double_t y = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+ return y; //fm^-4
+}
+
+Double_t AliFastGlauber::WIntRadius(const Double_t* x, const Double_t* par)
+{
+ //
+ // Average interaction density over radius
+ // at which interaction takes place
+ // as a function of radius
+ //
+ const Double_t kr = x[0];
+ const Double_t kb = par[0];
+ fgWAlmond->SetParameter(0, kb);
+ // Average over phi in small steps
+ const Double_t kdphi = 2. * TMath::Pi() / 100.;
+ Double_t phi = 0.;
+ Double_t y = 0.;
+ for (Int_t i = 0; i < 100; i++) {
+ const Double_t kxx = kr * TMath::Cos(phi);
+ const Double_t kyy = kr * TMath::Sin(phi);
+ y += fgWAlmond->Eval(kxx,kyy);
+ phi += kdphi;
+ } // phi loop
+ // Result multiplied by Jacobian (2 pi r)
+ y *= 2. * TMath::Pi() * kr / 100.;
+ return y; //fm^-3
+}
+
+Double_t AliFastGlauber::WPathLength0(const Double_t* x, const Double_t* par)
+{
+ //
+ // Path Length as a function of phi
+ // for interaction point fixed at (0,0)
+ // as a function of phi-direction
+ //
+ // Phi direction in Almond
+ const Double_t kphi0 = x[0];
+ const Double_t kb = par[0];
+ // Path Length definition
+ const Int_t kiopt = Int_t(par[1]);
+
+ // Step along radial direction phi
+ const Int_t kNp = 100; // Steps in r
+ const Double_t kDr = fgBMax/kNp;
+ Double_t r = 0.;
+ Double_t rw = 0.;
+ Double_t w = 0.;
+ for (Int_t i = 0; i < kNp; i++) {
+ //
+ // Transform into target frame
+ //
+ const Double_t kxx = r * TMath::Cos(kphi0) + kb / 2.;
+ const Double_t kyy = r * TMath::Sin(kphi0);
+ const Double_t kphi = TMath::ATan2(kyy, kxx);
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ // Radius in projectile frame
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + kb*kb - 2.*kr1*kb*TMath::Cos(kphi));
+ const Double_t ky = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+
+ rw += ky * r;
+ w += ky;
+ r += kDr;
+ } // radial steps
+
+ Double_t y=0.;
+ if (!kiopt) { // My length definition (is exact for hard disk)
+ if(w) y= 2. * rw / w;
+ } else {
+ const Double_t knorm=fgWSta->Eval(1e-4);
+ if(knorm) y = TMath::Sqrt(2. * rw * kDr / knorm / knorm);
+ }
+ return y; //fm
+}
+
+Double_t AliFastGlauber::WPathLength(const Double_t* x, const Double_t* par)
+{
+ //
+ // Path Length as a function of phi
+ // Interaction point from random distribution
+ // as a function of the phi-direction
+ const Double_t kphi0 = x[0];
+ const Double_t kb = par[0];
+ fgWAlmond->SetParameter(0, kb);
+ const Int_t kNpi = Int_t (par[1]); //Number of interactions
+ const Int_t kiopt = Int_t(par[2]); //Path Length definition
+
+ //
+ // r-steps
+ //
+ const Int_t kNp = 100;
+ const Double_t kDr = fgBMax/Double_t(kNp);
+ Double_t l = 0.; // Path length
+ for (Int_t in = 0; in < kNpi; in ++) {
Double_t rw = 0.;
Double_t w = 0.;
-// Step along radial direction phi
- for (Int_t i = 0; i < np; i++) {
-//
-// Transform into target frame
-//
- Double_t xx = r * TMath::Cos(phi0) + b / 2.;
- Double_t yy = r * TMath::Sin(phi0);
- Double_t phi = TMath::ATan2(yy, xx);
+ // Interaction point
+ Double_t x0, y0;
+ fgWAlmond->GetRandom2(x0, y0);
+ // Initial radius
+ const Double_t kr0 = TMath::Sqrt(x0*x0 + y0*y0);
+ const Int_t knps = Int_t ((fgBMax - kr0)/kDr) - 1;
- Double_t r1 = TMath::Sqrt(xx * xx + yy * yy);
-// Radius in projectile frame
- Double_t r2 = TMath::Sqrt(r1 * r1 + b * b - 2. * r1 * b * TMath::Cos(phi));
- Double_t y = fWSta->Eval(r1) * fWSta->Eval(r2);
-
- rw += y * r;
- w += y;
- r += dr;
- } // radial steps
-//
-// My length definition (is exact for hard disk)
- return (2. * rw / w);
+ // Radial steps
+ Double_t r = 0.;
+ for (Int_t i = 0; (i < knps ); i++) {
+ // Transform into target frame
+ const Double_t kxx = x0 + r * TMath::Cos(kphi0) + kb / 2.;
+ const Double_t kyy = y0 + r * TMath::Sin(kphi0);
+ const Double_t kphi = TMath::ATan2(kyy, kxx);
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ // Radius in projectile frame
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + kb*kb - 2.*kr1*kb*TMath::Cos(kphi));
+ const Double_t ky = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+
+ rw += ky * r;
+ w += ky;
+ r += kDr;
+ } // steps
+ // Average over interactions
+ if (!kiopt) {
+ if(w) l += (2. * rw / w);
+ } else {
+ const Double_t knorm=fgWSta->Eval(1e-4);
+ if(knorm) l+= 2. * rw * kDr / knorm / knorm;
+ }
+ } // interactions
+ Double_t ret=0;
+ if (!kiopt)
+ ret= l / kNpi;
+ else
+ ret=TMath::Sqrt( l / kNpi);
+ return ret; //fm
}
-Double_t AliFastGlauber::WPathLength(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::CrossSection(Double_t b1, Double_t b2) const
{
-//
-// Path Length as a function of phi
-// Interaction point from random distribution
-//
-//
-// r-steps
-//
- const Int_t np = 100;
- const Double_t dr = fbMax/Double_t(np);
-// Number of interactions
- const Int_t npi = Int_t (par[1]);
+ //
+ // Return the geometrical cross-section integrated from b1 to b2
+ //
+ return fgWSgeo->Integral(b1, b2)*10.; //mbarn
+}
-//
-// Impact parameter
- Double_t b = par[0];
-// Phi direction
- Double_t phi0 = x[0];
+Double_t AliFastGlauber::HardCrossSection(Double_t b1, Double_t b2) const
+{
+ //
+ // Return the hard cross-section integrated from b1 to b2
+ //
+ return fgWSbinary->Integral(b1, b2)*10.; //mbarn
+}
- printf("phi0 %f \n", phi0);
-
-// Path length
- Double_t l = 0.;
-
- for (Int_t in = 0; in < npi; in ++) {
- Double_t rw = 0.;
- Double_t w = 0.;
-
- // Interaction point
- Double_t x0, y0;
- fWAlmond->GetRandom2(x0, y0);
-// Initial radius
- Double_t r0 = TMath::Sqrt(x0 * x0 + y0 * y0);
- Int_t nps = Int_t ((fbMax - r0)/dr) - 1;
-
- Double_t r = 0.;
-// Radial steps
- for (Int_t i = 0; (i < nps ); i++) {
-
-// Transform into target frame
- Double_t xx = x0 + r * TMath::Cos(phi0) + b / 2.;
- Double_t yy = y0 + r * TMath::Sin(phi0);
- Double_t phi = TMath::ATan2(yy, xx);
- Double_t r1 = TMath::Sqrt(xx * xx + yy * yy);
-// Radius in projectile frame
- Double_t r2 = TMath::Sqrt(r1 * r1 + b * b - 2. * r1 * b * TMath::Cos(phi));
- Double_t y = fWSta->Eval(r1) * fWSta->Eval(r2);
-
- rw += y * r;
- w += y;
- r += dr;
- } // steps
-// Average over interactions
- l += 2. * rw / w;
- } // interactions
- return (l / Double_t(npi));
+Double_t AliFastGlauber::FractionOfHardCrossSection(Double_t b1, Double_t b2) const
+{
+ //
+ // Return fraction of hard cross-section integrated from b1 to b2
+ //
+ return fgWSbinary->Integral(b1, b2)/fgWSbinary->Integral(0., 100.);
}
-Double_t AliFastGlauber::WStaa(Double_t* x, Double_t* /*par*/)
+Double_t AliFastGlauber::NHard(const Double_t b1, const Double_t b2) const
{
-//
-// Overlap function
-//
- Double_t b = x[0];
- fWStarfi->SetParameter(0, b);
-/*
- Double_t al[2];
- Double_t bl[2];
- al[0] = 0.;
- al[1] = 0.;
- bl[0] = 6.6;
- bl[1] = TMath::Pi();
- Double_t err;
-
- Double_t y = 2. * fWStarfi->IntegralMultiple(2, al, bl, 0.001, err);
- printf("WStaa: %f %f %f\n", b, y, err);
-*/
-//
-// MC Integration
-//
- Double_t y = 0;
- for (Int_t i = 0; i < 100000; i++)
- {
- Double_t phi = TMath::Pi() * gRandom->Rndm();
- Double_t b1 = fbMax * gRandom->Rndm();
- y += fWStarfi->Eval(b1, phi);
- }
- y *= 2. * 0.1 * 208. * 208. * TMath::Pi() * fbMax / 100000.;
- return y;
+ //
+ // Number of binary hard collisions
+ // as a function of b (nucl/ex/0302016 eq. 19)
+ //
+ const Double_t kshard=HardCrossSection(b1,b2);
+ const Double_t ksgeo=CrossSection(b1,b2);
+ if(ksgeo>0)
+ return kshard/ksgeo;
+ else return -1;
}
-Double_t AliFastGlauber::WSgeo(Double_t* x, Double_t* /*par*/)
+Double_t AliFastGlauber::Binaries(Double_t b) const
+{
+ //
+ // Return number of binary hard collisions normalized to 1 at b=0
+ //
+ if(b < 1.e-4) b = 1e-4;
+ return fgWSN->Eval(b)/fgWSN->Eval(1e-4);
+}
+
+Double_t AliFastGlauber::MeanOverlap(Double_t b1, Double_t b2)
{
//
-// Geometrical Cross-Section
+// Calculate the mean overlap for impact parameter range b1 .. b2
//
- Double_t b = x[0];
- Double_t taa = fWStaa->Eval(b);
- const Double_t sigma = 55.6; // mbarn
+ Double_t sum = 0.;
+ Double_t sumc = 0.;
+ Double_t b = b1;
- Double_t y = 2. * TMath::Pi() * b * (1. - TMath::Exp(- sigma * taa)); // fm
- return y;
+ while (b < b2-0.005) {
+ Double_t nc = GetNumberOfCollisions(b);
+ sum += 10. * fgWStaa->Eval(b) * fgWSgeo->Eval(b) * 0.01 / (1. - TMath::Exp(-nc));
+ sumc += 10. * fgWSgeo->Eval(b) * 0.01;
+ b += 0.01;
+ }
+ return (sum / CrossSection(b1, b2));
}
-Double_t AliFastGlauber::WSbinary(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::MeanNumberOfCollisionsPerEvent(Double_t b1, Double_t b2)
{
//
-// Number of binary collisions
+// Calculate the mean number of collisions per event for impact parameter range b1 .. b2
//
- Double_t b = x[0];
- Double_t sigma = par[0];
- Double_t taa = fWStaa->Eval(b);
+ Double_t sum = 0.;
+ Double_t sumc = 0.;
+ Double_t b = b1;
- Double_t y = 2. * TMath::Pi() * b * sigma * taa; // fm
- return y;
+ while (b < b2-0.005) {
+ Double_t nc = GetNumberOfCollisions(b);
+ sum += nc / (1. - TMath::Exp(-nc)) * 10. * fgWSgeo->Eval(b) * 0.01;
+ sumc += 10. * fgWSgeo->Eval(b) * 0.01;
+ b += 0.01;
+ }
+ return (sum / CrossSection(b1, b2));
}
-Double_t AliFastGlauber::WSN(Double_t* x, Double_t* /*par*/)
+
+Double_t AliFastGlauber::GetNumberOfBinaries(Double_t b) const
{
-//
-// Number of hard processes per event
-//
- Double_t b = x[0];
- Double_t y = fWSbinary->Eval(b)/fWSgeo->Eval(b);
- return y;
+ //
+ // Return number of binary hard collisions at b
+ //
+ if(b<1.e-4) b=1e-4;
+ return fgWSN->Eval(b);
}
-Double_t AliFastGlauber::WEnergyDensity(Double_t* x, Double_t* par)
+Double_t AliFastGlauber::Participants(Double_t b) const
{
-//
-// Initial energy density as a function of the impact parameter
-//
- Double_t b = x[0];
- Double_t rA = par[0];
-//
-// Attention: area of transverse reaction zone in hard-sphere approximation !
- Double_t saa = (TMath::Pi() - 2. * TMath::ASin(b/ 2./ rA)) * rA * rA
- - b * TMath::Sqrt(rA * rA - b * b/ 4.);
- Double_t taa = fWStaa->Eval(b);
-
- return (taa/saa);
+ //
+ // Return the number of participants normalized to 1 at b=0
+ //
+ if(b<1.e-4) b=1e-4;
+ return (fgWParticipants->Eval(b)/fgWParticipants->Eval(1e-4));
}
-void AliFastGlauber::SimulateTrigger(Int_t n)
+Double_t AliFastGlauber::GetNumberOfParticipants(Double_t b) const
{
- //
- // Simulates Trigger
- //
- TH1F* mbtH = new TH1F("mbtH", "MB Trigger b-Distribution", 100, 0., 20.);
- TH1F* hdtH = new TH1F("hdtH", "Hard Trigger b-Distribution", 100, 0., 20.);
- TH1F* mbmH = new TH1F("mbmH", "MB Trigger Multiplicity Distribution", 100, 0., 8000.);
- TH1F* hdmH = new TH1F("hdmH", "Hard Trigger Multiplicity Distribution", 100, 0., 8000.);
+ //
+ // Return the number of participants for impact parameter b
+ //
+ if(b<1.e-4) b=1e-4;
+ return (fgWParticipants->Eval(b));
+}
- mbtH->SetXTitle("b [fm]");
- hdtH->SetXTitle("b [fm]");
- mbmH->SetXTitle("Multiplicity");
- hdmH->SetXTitle("Multiplicity");
+Double_t AliFastGlauber::GetNumberOfCollisions(Double_t b) const
+{
+ //
+ // Return the number of collisions for impact parameter b
+ //
+ if(b<1.e-4) b=1e-4;
+ return (fgWStaa->Eval(b)*fSigmaNN);
+}
- TCanvas *c0 = new TCanvas("c0","Trigger Simulation",400,10,600,700);
- c0->Divide(2,1);
- TCanvas *c1 = new TCanvas("c1","Trigger Simulation",400,10,600,700);
- c1->Divide(1,2);
+Double_t AliFastGlauber::GetNumberOfCollisionsPerEvent(Double_t b) const
+{
+ //
+ // Return the number of collisions per event (at least one collision)
+ // for impact parameter b
+ //
+ Double_t n = GetNumberOfCollisions(b);
+ if (n > 0.) {
+ return (n / (1. - TMath::Exp(- n)));
+ } else {
+ return (0.);
+ }
+}
- //
- //
- Init(1);
- for (Int_t iev = 0; iev < n; iev++)
+void AliFastGlauber::SimulateTrigger(Int_t n)
+{
+ //
+ // Simulates Trigger
+ //
+ TH1F* mbtH = new TH1F("mbtH", "MB Trigger b-Distribution", 100, 0., 20.);
+ TH1F* hdtH = new TH1F("hdtH", "Hard Trigger b-Distribution", 100, 0., 20.);
+ TH1F* mbmH = new TH1F("mbmH", "MB Trigger Multiplicity Distribution", 100, 0., 8000.);
+ TH1F* hdmH = new TH1F("hdmH", "Hard Trigger Multiplicity Distribution", 100, 0., 8000.);
+
+ mbtH->SetXTitle("b [fm]");
+ hdtH->SetXTitle("b [fm]");
+ mbmH->SetXTitle("Multiplicity");
+ hdmH->SetXTitle("Multiplicity");
+
+ TCanvas *c0 = new TCanvas("c0","Trigger Simulation",400,10,600,700);
+ c0->Divide(2,1);
+ TCanvas *c1 = new TCanvas("c1","Trigger Simulation",400,10,600,700);
+ c1->Divide(1,2);
+
+ //
+ //
+ Init(1);
+ for (Int_t iev = 0; iev < n; iev++)
{
- Float_t b, p, mult;
- GetRandom(b, p, mult);
- mbtH->Fill(b,1.);
- hdtH->Fill(b, p);
- mbmH->Fill(mult, 1.);
- hdmH->Fill(mult, p);
-
- c0->cd(1);
- mbtH->Draw();
- c0->cd(2);
- hdtH->Draw();
- c0->Update();
-
- c1->cd(1);
- mbmH->Draw();
- c1->cd(2);
- hdmH->Draw();
- c1->Update();
+ Float_t b, p, mult;
+ GetRandom(b, p, mult);
+ mbtH->Fill(b,1.);
+ hdtH->Fill(b, p);
+ mbmH->Fill(mult, 1.);
+ hdmH->Fill(mult, p);
+
+ c0->cd(1);
+ mbtH->Draw();
+ c0->cd(2);
+ hdtH->Draw();
+ c0->Update();
+
+ c1->cd(1);
+ mbmH->Draw();
+ c1->cd(2);
+ hdmH->Draw();
+ c1->Update();
}
}
void AliFastGlauber::GetRandom(Float_t& b, Float_t& p, Float_t& mult)
{
- //
- // Gives back a random impact parameter, hard trigger probability and multiplicity
- //
- b = fWSgeo->GetRandom();
- Float_t mu = fWSN->Eval(b);
- p = 1.-TMath::Exp(-mu);
- mult = 6000./fWSN->Eval(1.) * mu;
+ //
+ // Gives back a random impact parameter, hard trigger probability and multiplicity
+ //
+ b = fgWSgeo->GetRandom();
+ const Float_t kmu = fgWSN->Eval(b);
+ p = 1.-TMath::Exp(-kmu);
+ mult = 6000./fgWSN->Eval(1.) * kmu;
}
void AliFastGlauber::GetRandom(Int_t& bin, Bool_t& hard)
{
- //
- // Gives back a random impact parameter bin, and hard trigger decission
- //
- Float_t b = fWSgeo->GetRandom();
- Float_t mu = fWSN->Eval(b) * fSigmaHard;
- Float_t p = 1.-TMath::Exp(-mu);
- if (b < 5.) {
- bin = 1;
- } else if (b < 8.6) {
- bin = 2;
- } else if (b < 11.2) {
- bin = 3;
- } else if (b < 13.2) {
- bin = 4;
- } else if (b < 15.0) {
- bin = 5;
- } else {
- bin = 6;
- }
-
- hard = kFALSE;
-
- Float_t r = gRandom->Rndm();
-
- if (r < p) hard = kTRUE;
+ //
+ // Gives back a random impact parameter bin, and hard trigger decission
+ //
+ const Float_t kb = fgWSgeo->GetRandom();
+ const Float_t kmu = fgWSN->Eval(kb) * fSigmaHard;
+ const Float_t kp = 1.-TMath::Exp(-kmu);
+ if (kb < 5.) {
+ bin = 1;
+ } else if (kb < 8.6) {
+ bin = 2;
+ } else if (kb < 11.2) {
+ bin = 3;
+ } else if (kb < 13.2) {
+ bin = 4;
+ } else if (kb < 15.0) {
+ bin = 5;
+ } else {
+ bin = 6;
+ }
+ hard = kFALSE;
+ const Float_t kr = gRandom->Rndm();
+ if (kr < kp) hard = kTRUE;
}
+Double_t AliFastGlauber::GetRandomImpactParameter(Double_t bmin, Double_t bmax)
+{
+ //
+ // Gives back a random impact parameter in the range bmin .. bmax
+ //
+ Float_t b = -1.;
+ while(b < bmin || b > bmax)
+ b = fgWSgeo->GetRandom();
+ return b;
+}
-Float_t AliFastGlauber::GetRandomImpactParameter(Float_t bmin, Float_t bmax)
+void AliFastGlauber::StoreFunctions() const
{
- //
- // Gives back a random impact parameter in the range bmin .. bmax
- //
+ //
+ // Store in file functions
+ //
+ TFile* ff = new TFile(fName.Data(),"recreate");
+ fgWStaa->Write("WStaa");
+ fgWParticipants->Write("WParticipants");
+ ff->Close();
+ return;
+}
+
+//=================== Added by A. Dainese 11/02/04 ===========================
- Float_t b = -1.;
- while(b < bmin || b > bmax)
- b = fWSgeo->GetRandom();
- return b;
+void AliFastGlauber::StoreAlmonds() const
+{
+ //
+ // Store in file
+ // 40 almonds for b = (0.25+k*0.5) fm (k=0->39)
+ //
+ Char_t almondName[100];
+ TFile* ff = new TFile(fName.Data(),"update");
+ for(Int_t k=0; k<40; k++) {
+ snprintf(almondName, 100, "WAlmondFixedB%d",k);
+ Double_t b = 0.25+k*0.5;
+ Info("StoreAlmonds"," b = %f\n",b);
+ fgWAlmond->SetParameter(0,b);
+ fgWAlmond->Write(almondName);
+ }
+ ff->Close();
+ return;
+}
+
+void AliFastGlauber::SetCentralityClass(Double_t xsecFrLow,Double_t xsecFrUp)
+{
+ //
+ // Set limits of centrality class as fractions
+ // of the geomtrical cross section
+ //
+ if(xsecFrLow>1. || xsecFrUp>1. || xsecFrLow>xsecFrUp) {
+ Error("SetCentralityClass", "Please set 0 <= xsecFrLow <= xsecFrUp <= 1\n");
+ return;
+ }
+
+ Double_t bLow=0.,bUp=0.;
+ Double_t xsecFr=0.;
+ const Double_t knorm=fgWSgeo->Integral(0.,100.);
+ while(xsecFr<xsecFrLow) {
+ xsecFr = fgWSgeo->Integral(0.,bLow)/knorm;
+ bLow += 0.1;
+ }
+ bUp = bLow;
+ while(xsecFr<xsecFrUp) {
+ xsecFr = fgWSgeo->Integral(0.,bUp)/knorm;
+ bUp += 0.1;
+ }
+
+ Info("SetCentralityClass", "Centrality class: %4.2f-%4.2f; %4.1f < b < %4.1f fm",
+ xsecFrLow,xsecFrUp,bLow,bUp);
+ fgWSbinary->SetRange(bLow,bUp);
+ fBmin=bLow;
+ fBmax=bUp;
+ return;
+}
+
+void AliFastGlauber::GetRandomBHard(Double_t& b)
+{
+ //
+ // Get random impact parameter according to distribution of
+ // hard (binary) cross-section, in the range defined by the centrality class
+ //
+ b = fgWSbinary->GetRandom();
+ Int_t bin = 2*(Int_t)b;
+ if( (b-(Int_t)b) > 0.5) bin++;
+ fgWAlmondCurrent = fgWAlmondFixedB[bin];
+ return;
+}
+
+void AliFastGlauber::GetRandomXY(Double_t& x,Double_t& y)
+{
+ //
+ // Get random position of parton production point according to
+ // product of thickness functions
+ //
+ fgWAlmondCurrent->GetRandom2(x,y);
+ return;
}
-Double_t AliFastGlauber::CrossSection(Double_t b1, Double_t b2)
+void AliFastGlauber::GetRandomPhi(Double_t& phi)
{
+ //
+ // Get random parton azimuthal propagation direction
+ //
+ phi = 2.*TMath::Pi()*gRandom->Rndm();
+ return;
+}
+
+Double_t AliFastGlauber::CalculateLength(Double_t b,Double_t x0,Double_t y0,Double_t phi0)
+{
+ //
+ // Calculate path length for a parton with production point (x0,y0)
+ // and propagation direction (ux=cos(phi0),uy=sin(phi0))
+ // in a collision with impact parameter b
+ //
+
+ // number of steps in l
+ const Int_t kNp = 100;
+ const Double_t kDl = fgBMax/Double_t(kNp);
+
+ if(fEllDef==1) {
//
- // Return cross-section integrated from b1 to b2
+ // Definition 1:
+ //
+ // ell = 2 * \int_0^\infty dl*l*(T_A*T_B)(x0+l*ux,y0+l*uy) /
+ // \int_0^\infty dl*(T_A*T_B)(x0+l*ux,y0+l*uy)
//
+
+ // Initial radius
+ const Double_t kr0 = TMath::Sqrt(x0*x0 + y0*y0);
+ const Int_t knps = Int_t ((fgBMax - kr0)/kDl) - 1;
+ Double_t l = 0.;
+ Double_t integral1 = 0.;
+ Double_t integral2 = 0.;
+ // Radial steps
+ for (Int_t i = 0; i < knps; i++) {
+
+ // Transform into target frame
+ const Double_t kxx = x0 + l * TMath::Cos(phi0) + b / 2.;
+ const Double_t kyy = y0 + l * TMath::Sin(phi0);
+ const Double_t kphi = TMath::ATan2(kyy, kxx);
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ // Radius in projectile frame
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + b*b - 2.*kr1*b*TMath::Cos(kphi));
+ const Double_t kprodTATB = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+
+ integral1 += kprodTATB * l * kDl;
+ integral2 += kprodTATB * kDl;
+ l += kDl;
+ } // steps
- return fWSgeo->Integral(b1, b2)/100.;
+ Double_t ell=0.;
+ if(integral2)
+ ell = (2. * integral1 / integral2);
+ return ell;
+ } else if(fEllDef==2) {
+ //
+ // Definition 2:
+ //
+ // ell = \int_0^\infty dl*
+ // \Theta((T_A*T_B)(x0+l*ux,y0+l*uy)-0.5*(T_A*T_B)(0,0))
+ //
+
+ // Initial radius
+ const Double_t kr0 = TMath::Sqrt(x0*x0 + y0*y0);
+ const Int_t knps = Int_t ((fgBMax - kr0)/kDl) - 1;
+ const Double_t kprodTATBHalfMax = 0.5*fgWAlmondCurrent->Eval(0.,0.);
+ // Radial steps
+ Double_t l = 0.;
+ Double_t integral = 0.;
+ for (Int_t i = 0; i < knps; i++) {
+ // Transform into target frame
+ const Double_t kxx = x0 + l * TMath::Cos(phi0) + b / 2.;
+ const Double_t kyy = y0 + l * TMath::Sin(phi0);
+ const Double_t kphi = TMath::ATan2(kyy, kxx);
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ // Radius in projectile frame
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + b*b - 2.*kr1*b*TMath::Cos(kphi));
+ const Double_t kprodTATB = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+ if(kprodTATB>kprodTATBHalfMax) integral += kDl;
+ l += kDl;
+ } // steps
+ Double_t ell = integral;
+ return ell;
+ } else {
+ Error("CalculateLength","Wrong length definition setting: %d !\n",fEllDef);
+ return -1.;
+ }
}
-Double_t AliFastGlauber::FractionOfHardCrossSection(Double_t b1, Double_t b2)
+void AliFastGlauber::GetLengthAndPhi(Double_t& ell,Double_t& phi,Double_t b)
{
- //
- // Return raction of hard cross-section integrated from b1 to b2
- //
+ //
+ // Return length from random b, x0, y0, phi0
+ // Return also phi0
+ //
+ Double_t x0,y0,phi0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ GetRandomPhi(phi0);
+ phi = phi0;
+ ell = CalculateLength(b,x0,y0,phi0);
+ return;
+}
+
+void AliFastGlauber::GetLength(Double_t& ell,Double_t b)
+{
+ //
+ // Return length from random b, x0, y0, phi0
+ //
+ Double_t phi;
+ GetLengthAndPhi(ell,phi,b);
+ return;
+}
+
+void AliFastGlauber::GetLengthsBackToBackAndPhi(Double_t& ell1,Double_t& ell2,Double_t &phi,Double_t b)
+{
+ //
+ // Return 2 lengths back to back from random b, x0, y0, phi0
+ // Return also phi0
+ //
+ Double_t x0,y0,phi0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ GetRandomPhi(phi0);
+ const Double_t kphi0plusPi = phi0+TMath::Pi();
+ phi = phi0;
+ ell1 = CalculateLength(b,x0,y0,phi0);
+ ell2 = CalculateLength(b,x0,y0,kphi0plusPi);
+ return;
+}
+
+void AliFastGlauber::GetLengthsBackToBack(Double_t& ell1,Double_t& ell2,
+ Double_t b)
+{
+ //
+ // Return 2 lengths back to back from random b, x0, y0, phi0
+ //
+ Double_t phi;
+ GetLengthsBackToBackAndPhi(ell1,ell2,phi,b);
+ return;
+}
+
+void AliFastGlauber::GetLengthsForPythia(Int_t n,Double_t* const phi,Double_t* ell, Double_t b)
+{
+ //
+ // Returns lenghts for n partons with azimuthal angles phi[n]
+ // from random b, x0, y0
+ //
+ Double_t x0, y0;
+ if(b < 0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ for(Int_t i = 0; i< n; i++) ell[i] = CalculateLength(b,x0,y0,phi[i]);
+ return;
+}
+
+void AliFastGlauber::PlotBDistr(Int_t n)
+{
+ //
+ // Plot distribution of n impact parameters
+ //
+ Double_t b;
+ TH1F *hB = new TH1F("hB","dN/db",100,0,fgBMax);
+ hB->SetXTitle("b [fm]");
+ hB->SetYTitle("dN/db [a.u.]");
+ hB->SetFillColor(3);
+ for(Int_t i=0; i<n; i++) {
+ GetRandomBHard(b);
+ hB->Fill(b);
+ }
+ TCanvas *cB = new TCanvas("cB","Impact parameter distribution",0,0,500,500);
+ cB->cd();
+ hB->Draw();
+ return;
+}
+
+void AliFastGlauber::PlotLengthDistr(Int_t n,Bool_t save,const char *fname)
+{
+ //
+ // Plot length distribution
+ //
+ Double_t ell;
+ TH1F *hEll = new TH1F("hEll","Length distribution",64,-0.5,15);
+ hEll->SetXTitle("Transverse path length, L [fm]");
+ hEll->SetYTitle("Probability");
+ hEll->SetFillColor(2);
+ for(Int_t i=0; i<n; i++) {
+ GetLength(ell);
+ hEll->Fill(ell);
+ }
+ hEll->Scale(1/(Double_t)n);
+ TCanvas *cL = new TCanvas("cL","Length distribution",0,0,500,500);
+ cL->cd();
+ hEll->Draw();
+
+ if(save) {
+ TFile *f = new TFile(fname,"recreate");
+ hEll->Write();
+ f->Close();
+ }
+ return;
+}
+
+void AliFastGlauber::PlotLengthB2BDistr(Int_t n,Bool_t save,const char *fname)
+{
+ //
+ // Plot lengths back-to-back distributions
+ //
+ Double_t ell1,ell2;
+ TH2F *hElls = new TH2F("hElls","Lengths back-to-back",100,0,15,100,0,15);
+ hElls->SetXTitle("Transverse path length, L [fm]");
+ hElls->SetYTitle("Transverse path length, L [fm]");
+ for(Int_t i=0; i<n; i++) {
+ GetLengthsBackToBack(ell1,ell2);
+ hElls->Fill(ell1,ell2);
+ }
+ hElls->Scale(1/(Double_t)n);
+ TCanvas *cLs = new TCanvas("cLs","Length back-to-back distribution",0,0,500,500);
+ gStyle->SetPalette(1,0);
+ cLs->cd();
+ hElls->Draw("col,Z");
+ if(save) {
+ TFile *f = new TFile(fname,"recreate");
+ hElls->Write();
+ f->Close();
+ }
+ return;
+}
+
+void AliFastGlauber::PlotAlmonds() const
+{
+ //
+ // Plot almonds for some impact parameters
+ //
+ TCanvas *c = new TCanvas("c","Almonds",0,0,500,500);
+ gStyle->SetPalette(1,0);
+ c->Divide(2,2);
+ c->cd(1);
+ fgWAlmondFixedB[0]->Draw("cont1");
+ c->cd(2);
+ fgWAlmondFixedB[10]->Draw("cont1");
+ c->cd(3);
+ fgWAlmondFixedB[20]->Draw("cont1");
+ c->cd(4);
+ fgWAlmondFixedB[30]->Draw("cont1");
+ return;
+}
+
+//=================== Added by A. Dainese 05/03/04 ===========================
+
+void AliFastGlauber::CalculateI0I1(Double_t& integral0,Double_t& integral1,
+ Double_t b,Double_t x0,Double_t y0,
+ Double_t phi0,Double_t ellCut) const
+{
+ //
+ // Calculate integrals:
+ // integral0 = \int_0^ellCut dl*(T_A*T_B)(x0+l*ux,y0+l*uy)
+ // integral1 = \int_0^ellCut dl*l*(T_A*T_B)(x0+l*ux,y0+l*uy)
+ //
+ // for a parton with production point (x0,y0)
+ // and propagation direction (ux=cos(phi0),uy=sin(phi0))
+ // in a collision with impact parameter b
+ //
+
+ // number of steps in l
+ const Int_t kNp = 100;
+ const Double_t kDl = fgBMax/Double_t(kNp);
- return fWSbinary->Integral(b1, b2)/fWSbinary->Integral(0., 100.);
+ // Initial radius
+ const Double_t kr0 = TMath::Sqrt(x0 * x0 + y0 * y0);
+ const Int_t knps = Int_t ((fgBMax - kr0)/kDl) - 1;
+
+ // Radial steps
+ Double_t l = 0.;
+ integral0 = 0.;
+ integral1 = 0.;
+ Int_t i = 0;
+ while((i < knps) && (l < ellCut)) {
+ // Transform into target frame
+ const Double_t kxx = x0 + l * TMath::Cos(phi0) + b / 2.;
+ const Double_t kyy = y0 + l * TMath::Sin(phi0);
+ const Double_t kphi = TMath::ATan2(kyy, kxx);
+ const Double_t kr1 = TMath::Sqrt(kxx*kxx + kyy*kyy);
+ // Radius in projectile frame
+ const Double_t kr2 = TMath::Sqrt(kr1*kr1 + b*b - 2.*kr1*b*TMath::Cos(kphi));
+ const Double_t kprodTATB = fgWSta->Eval(kr1) * fgWSta->Eval(kr2);
+ integral0 += kprodTATB * kDl;
+ integral1 += kprodTATB * l * kDl;
+ l += kDl;
+ i++;
+ } // steps
+ return;
+}
+
+void AliFastGlauber::GetI0I1AndPhi(Double_t& integral0,Double_t& integral1,
+ Double_t& phi,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Return I0 and I1 from random b, x0, y0, phi0
+ // Return also phi
+ //
+ Double_t x0,y0,phi0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ GetRandomPhi(phi0);
+ phi = phi0;
+ CalculateI0I1(integral0,integral1,b,x0,y0,phi0,ellCut);
+ return;
+}
+
+void AliFastGlauber::GetI0I1(Double_t& integral0,Double_t& integral1,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Return I0 and I1 from random b, x0, y0, phi0
+ //
+ Double_t phi;
+ GetI0I1AndPhi(integral0,integral1,phi,ellCut,b);
+ return;
}
+void AliFastGlauber::GetI0I1BackToBackAndPhi(Double_t& integral01,Double_t& integral11,
+ Double_t& integral02,Double_t& integral12,
+ Double_t& phi,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Return 2 pairs of I0 and I1 back to back from random b, x0, y0, phi0
+ // Return also phi0
+ //
+ Double_t x0,y0,phi0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ GetRandomPhi(phi0);
+ phi = phi0;
+ const Double_t kphi0plusPi = phi0+TMath::Pi();
+ CalculateI0I1(integral01,integral11,b,x0,y0,phi0,ellCut);
+ CalculateI0I1(integral02,integral12,b,x0,y0,kphi0plusPi,ellCut);
+ return;
+}
+
+void AliFastGlauber::GetI0I1BackToBackAndPhiAndXY(Double_t& integral01,Double_t& integral11,
+ Double_t& integral02,Double_t& integral12,
+ Double_t& phi,Double_t &x,Double_t &y,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Return 2 pairs of I0 and I1 back to back from random b, x0, y0, phi0
+ // Return also phi0
+ //
+ Double_t x0,y0,phi0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ GetRandomPhi(phi0);
+ phi = phi0; x=x0; y=y0;
+ const Double_t kphi0plusPi = phi0+TMath::Pi();
+ CalculateI0I1(integral01,integral11,b,x0,y0,phi0,ellCut);
+ CalculateI0I1(integral02,integral12,b,x0,y0,kphi0plusPi,ellCut);
+ return;
+}
+
+void AliFastGlauber::GetI0I1BackToBack(Double_t& integral01,Double_t& integral11,
+ Double_t& integral02,Double_t& integral12,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Return 2 pairs of I0 and I1 back to back from random b, x0, y0, phi0
+ //
+ Double_t phi;
+ GetI0I1BackToBackAndPhi(integral01,integral11,integral02,integral12,
+ phi,ellCut,b);
+ return;
+}
-Double_t AliFastGlauber::Binaries(Double_t b)
+void AliFastGlauber::GetI0I1ForPythia(Int_t n,Double_t* phi,
+ Double_t* integral0,Double_t* integral1,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Returns I0 and I1 pairs for n partons with azimuthal angles phi[n]
+ // from random b, x0, y0
+ //
+ Double_t x0,y0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ for(Int_t i=0; i<n; i++)
+ CalculateI0I1(integral0[i],integral1[i],b,x0,y0,phi[i],ellCut);
+ return;
+}
+
+void AliFastGlauber::GetI0I1ForPythiaAndXY(Int_t n,Double_t* phi,
+ Double_t* integral0,Double_t* integral1,
+ Double_t &x,Double_t& y,
+ Double_t ellCut,Double_t b)
+{
+ //
+ // Returns I0 and I1 pairs for n partons with azimuthal angles phi[n]
+ // from random b, x0, y0 and return x0,y0
+ //
+ Double_t x0,y0;
+ if(b<0.) GetRandomBHard(b);
+ GetRandomXY(x0,y0);
+ for(Int_t i=0; i<n; i++)
+ CalculateI0I1(integral0[i],integral1[i],b,x0,y0,phi[i],ellCut);
+ x=x0;
+ y=y0;
+ return;
+}
+
+void AliFastGlauber::PlotI0I1Distr(Int_t n,Double_t ellCut,
+ Bool_t save,const char *fname)
+{
+ //
+ // Plot I0-I1 distribution
+ //
+ Double_t i0,i1;
+ TH2F *hI0I1s = new TH2F("hI0I1s","I_{0} versus I_{1}",1000,0,0.001,1000,0,0.01);
+ hI0I1s->SetXTitle("I_{0} [fm^{-3}]");
+ hI0I1s->SetYTitle("I_{1} [fm^{-2}]");
+
+ TH1F *hI0 = new TH1F("hI0","I_{0} = #hat{q}L / k",
+ 1000,0,0.001);
+ hI0->SetXTitle("I_{0} [fm^{-3}]");
+ hI0->SetYTitle("Probability");
+ hI0->SetFillColor(3);
+ TH1F *hI1 = new TH1F("hI1","I_{1} = #omega_{c} / k",
+ 1000,0,0.01);
+ hI1->SetXTitle("I_{1} [fm^{-2}]");
+ hI1->SetYTitle("Probability");
+ hI1->SetFillColor(4);
+ TH1F *h2 = new TH1F("h2","2 I_{1}^{2}/I_{0} = R / k",
+ 100,0,0.02);
+ h2->SetXTitle("2 I_{1}^{2}/I_{0} [fm^{-1}]");
+ h2->SetYTitle("Probability");
+ h2->SetFillColor(2);
+ TH1F *h3 = new TH1F("h3","2 I_{1}/I_{0} = L",
+ 100,0,15);
+ h3->SetXTitle("2 I_{1}/I_{0} [fm]");
+ h3->SetYTitle("Probability");
+ h3->SetFillColor(5);
+ TH1F *h4 = new TH1F("h4","I_{0}^{2}/(2 I_{1}) = #hat{q} / k",
+ 100,0,0.00015);
+ h4->SetXTitle("I_{0}^{2}/(2 I_{1}) [fm^{-4}]");
+ h4->SetYTitle("Probability");
+ h4->SetFillColor(7);
+
+ for(Int_t i=0; i<n; i++) {
+ GetI0I1(i0,i1,ellCut);
+ hI0I1s->Fill(i0,i1);
+ hI0->Fill(i0);
+ hI1->Fill(i1);
+ h2->Fill(2.*i1*i1/i0);
+ h3->Fill(2.*i1/i0);
+ h4->Fill(i0*i0/2./i1);
+ }
+ hI0->Scale(1/(Double_t)n);
+ hI1->Scale(1/(Double_t)n);
+ h2->Scale(1/(Double_t)n);
+ h3->Scale(1/(Double_t)n);
+ h4->Scale(1/(Double_t)n);
+ hI0I1s->Scale(1/(Double_t)n);
+
+ TCanvas *cI0I1 = new TCanvas("cI0I1","I0 and I1",0,0,900,700);
+ cI0I1->Divide(3,2);
+ cI0I1->cd(1);
+ hI0->Draw();
+ cI0I1->cd(2);
+ hI1->Draw();
+ cI0I1->cd(3);
+ h2->Draw();
+ cI0I1->cd(4);
+ h3->Draw();
+ cI0I1->cd(5);
+ h4->Draw();
+ cI0I1->cd(6);
+ gStyle->SetPalette(1,0);
+ hI0I1s->Draw("col,Z");
+
+ if(save) {
+ TFile *f = new TFile(fname,"recreate");
+ hI0I1s->Write();
+ hI0->Write();
+ hI1->Write();
+ h2->Write();
+ h3->Write();
+ h4->Write();
+ f->Close();
+ }
+ return;
+}
+
+void AliFastGlauber::PlotI0I1B2BDistr(Int_t n,Double_t ellCut,
+ Bool_t save,const char *fname)
+{
+ //
+ // Plot I0-I1 back-to-back distributions
+ //
+ Double_t i01,i11,i02,i12;
+ TH2F *hI0s = new TH2F("hI0s","I_{0}'s back-to-back",100,0,100,100,0,100);
+ hI0s->SetXTitle("I_{0} [fm^{-3}]");
+ hI0s->SetYTitle("I_{0} [fm^{-3}]");
+ TH2F *hI1s = new TH2F("hI1s","I_{1}'s back-to-back",100,0,100,100,0,100);
+ hI1s->SetXTitle("I_{1} [fm^{-2}]");
+ hI1s->SetYTitle("I_{1} [fm^{-2}]");
+
+ for(Int_t i=0; i<n; i++) {
+ GetI0I1BackToBack(i01,i11,i02,i12,ellCut);
+ hI0s->Fill(i01,i02);
+ hI1s->Fill(i11,i12);
+ }
+ hI0s->Scale(1/(Double_t)n);
+ hI1s->Scale(1/(Double_t)n);
+
+ TCanvas *cI0I1s = new TCanvas("cI0I1s","I0 and I1 back-to-back distributions",0,0,800,400);
+ gStyle->SetPalette(1,0);
+ cI0I1s->Divide(2,1);
+ cI0I1s->cd(1);
+ hI0s->Draw("col,Z");
+ cI0I1s->cd(2);
+ hI1s->Draw("col,Z");
+
+ if(save) {
+ TFile *f = new TFile(fname,"recreate");
+ hI0s->Write();
+ hI1s->Write();
+ f->Close();
+ }
+ return;
+}
+
+AliFastGlauber& AliFastGlauber::operator=(const AliFastGlauber& rhs)
+{
+// Assignment operator
+ rhs.Copy(*this);
+ return *this;
+}
+
+void AliFastGlauber::Copy(TObject&) const
{
//
- // Return number of binary collisions normalized to 1 at b=0
+ // Copy
//
-
- return fWSN->Eval(b)/fWSN->Eval(0.001);
+ Fatal("Copy","Not implemented!\n");
}
+