+/**************************************************************************
+ * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
+ * *
+ * Author: The ALICE Off-line Project. *
+ * Contributors are mentioned in the code where appropriate. *
+ * *
+ * Permission to use, copy, modify and distribute this software and its *
+ * documentation strictly for non-commercial purposes is hereby granted *
+ * without fee, provided that the above copyright notice appears in all *
+ * copies and that both the copyright notice and this permission notice *
+ * appear in the supporting documentation. The authors make no claims *
+ * about the suitability of this software for any purpose. It is *
+ * provided "as is" without express or implied warranty. *
+ **************************************************************************/
+
+/* $Id$ */
+
+
+
//-------------------------------------------------------------
// Generate Beam-Gas-Events
// Default: underlying event: pO @ 7 TeV (fixed target)
//
// underlying event can be changed by adding generators
-// in the same as to AliGenCocktail before calling the Init()
+// in the same way as to AliGenCocktail before calling
+// the Init()
+// Author: Jochen Klein
//-------------------------------------------------------------
-/* $Id$ */
-
#include <TList.h>
#include <TObjArray.h>
-#include "TParticle.h"
+#include <TParticle.h>
#include "AliGenBeamGasNew.h"
#include "AliGenCocktail.h"
#include "AliStack.h"
#include "AliLog.h"
+#include "AliHeader.h"
+#include "AliGenEventHeader.h"
+
ClassImp(AliGenBeamGasNew)
Float_t EtaToTheta(Float_t arg) { return (180./TMath::Pi())*2.*atan(exp(-arg)); }
AliGenBeamGasNew::AliGenBeamGasNew() :
AliGenCocktail(),
- fTwindow(88.e-6)
+ fItime(0),
+ fTwindow(88e-6),
+ fZwindow(2000),
+ fRate(1e3)
{
- // Default constructor
+ // Default constructor
}
AliGenBeamGasNew::~AliGenBeamGasNew()
{
- // Destructor
}
-AliGenBeamGasNew::AliGenBeamGasNew(const AliGenBeamGasNew& /*rhs*/) : AliGenCocktail()
-{
- AliFatal("Copy Constructor not yet implemented!");
+void AliGenBeamGasNew::SetTimeWindow(Float_t twindow) { fTwindow = twindow; }
+
+bool AliGenBeamGasNew::SetRate(Float_t rate) {
+ if (rate >= 0) {
+ fRate = rate;
+ return true;
+ } else
+ return false;
}
+void AliGenBeamGasNew::SetZWindow(Float_t zwindow) { fZwindow = zwindow; }
void AliGenBeamGasNew::Init()
{
// p-O-collision at 7 TeV (fixed target)
if (!fEntries) {
AliGenHijing *gen = new AliGenHijing(-1);
- gen->SetEnergyCMS(7000);
gen->SetReferenceFrame("LAB");
+ gen->SetEnergyCMS(7000);
gen->SetProjectile("P",1,1);
gen->SetTarget("A",16,8);
gen->SetPhiRange(0,360);
gen->SetDecaysOff(1);
gen->SetSpectators(1);
gen->SetSelectAll(1);
- gen->SetRandomPz(kTRUE);
+ gen->SetRandomPz(kFALSE);
gen->SetPileUpTimeWindow(0.);
AddGenerator(gen,"Hijing pO",1);
}
// Loop over generators and initialize
while((entry = (AliGenCocktailEntry*)next())) {
- if (fStack) entry->Generator()->SetStack(fStack);
- entry->Generator()->Init();
+ if (fStack) entry->Generator()->SetStack(fStack);
+ entry->Generator()->Init();
}
next.Reset();
{
// calculation of the interaction vertex for the beam gas event
// both spatial and time coordinate are adjusted.
-
- Float_t random[2];
- Float_t nbunch;
- Int_t bunch;
-
- Rndm(random,2);
- fVertex[0] = fVertex[1] = 0.;
- fVertex[2] = random[1] * 4000. - 2000.;
- AliInfo(Form("z-Koord.: %13.3f \n", fVertex[2]));
- nbunch = 2 * fTwindow / 25.e-9;
- bunch = (Int_t) (nbunch * (random[0] - 0.5));
- fItime = fVertex[2] / 3.e8 + bunch * 25.e-9;
- AliInfo(Form("fItime: %13.3e \n", fItime));
+
+ Float_t random[2];
+ Float_t nbunch;
+ Float_t bunch;
+
+ gRandom->RndmArray(2,random);
+ fVertex[0] = fVertex[1] = 0;
+ fVertex[2] = random[0] * 2 * fZwindow - fZwindow;
+ nbunch = fTwindow/25e-9;
+ bunch = floor(2*nbunch * random[1] - nbunch);
+ fItime = fVertex[2] / 100 / 3e8 + bunch * 25e-9;
+ AliInfo(Form("fItime: %13.3e \n", fItime));
}
void AliGenBeamGasNew::Generate()
{
+//
+// Generate the collisions for one event
+//
+ Int_t numbg = gRandom->Poisson(fRate*fZwindow/100*2*fTwindow);
+ if (numbg == 0) return;
+
TIter next(fEntries);
AliGenCocktailEntry *entry = 0;
AliGenCocktailEntry *preventry = 0;
AliGenerator* gen = 0;
+ TLorentzVector v;
+ TArrayF eventVertex;
+ Int_t lastpart=0;
+ Float_t sign;
if (fHeader) delete fHeader;
fHeader = new AliGenCocktailEventHeader("Beamgas Header");
TObjArray *partArray = gAlice->GetMCApp()->Particles();
+ AliStack *stack = gAlice->GetRunLoader()->Stack();
- TArrayF eventVertex;
- int numbg = 0; // variable for counting how many bg interactions happened
-
- do {
- numbg++;
+ for (Int_t l = 0; l < numbg; l++) {
Vertex();
+ sign = (gRandom->Rndm() < 0.5)? -1. : 1.;
eventVertex.Set(3);
for (Int_t j=0; j < 3; j++) eventVertex[j] = fVertex[j];
igen++;
if (igen ==1) {
- entry->SetFirst(0);
+ entry->SetFirst(lastpart);
} else {
entry->SetFirst((partArray->GetEntriesFast())+1);
}
//
// Select a generator randomly
//
- Int_t i;
+ Int_t i = 0;
Float_t p0 = gRandom->Rndm();
for (i = 0; i < fNGenerators; i++) {
}
entry = (AliGenCocktailEntry*) fEntries->At(i);
- entry->SetFirst(0);
+ entry->SetFirst(lastpart);
gen = entry->Generator();
entry->Generator()->SetVertex(fVertex.At(0), fVertex.At(1), fVertex.At(2));
entry->Generator()->Generate();
entry->SetLast(partArray->GetEntriesFast());
}
- AliStack *stack = gAlice->GetRunLoader()->Stack();
- TLorentzVector v;
- for (int k = 0; k < stack->GetNprimary(); k++) {
+ for (Int_t k = lastpart; k < stack->GetNprimary(); k++) {
stack->Particle(k)->ProductionVertex(v);
- v[3] += fItime;
+ v[2] *= sign;
+ eventVertex[2] *= sign;
+ v[3] = fItime; // ??? +=
stack->Particle(k)->SetProductionVertex(v);
+ stack->Particle(k)->Momentum(v);
+ v[2] *= sign;
+ stack->Particle(k)->SetMomentum(v);
}
-
+
+ ((AliGenEventHeader*) fHeader->GetHeaders()->Last())->SetPrimaryVertex(eventVertex);
+
+ lastpart = stack->GetNprimary();
next.Reset();
- } while (gRandom->Rndm() < 1. / 5.); // must be adjusted to the rate of bg interactions
- // Event Vertex
- fHeader->SetPrimaryVertex(eventVertex);
- // Total number of produced an stored particles
+ }
+
fHeader->CalcNProduced();
- gAlice->SetGenEventHeader(fHeader);
+ if (fContainer) {
+ fContainer->AddHeader(fHeader);
+ } else {
+ gAlice->SetGenEventHeader(fHeader);
+ }
}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff