1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
19 // Generator for particles in a preset
20 // kinematic range (flat distribution)
21 // Note that for a given theta pt and p are not independent
22 // Range for only one variable (pt or p) should be given.
23 // Comments and suggestions: andreas.morsch@cern.ch
29 #include "AliGenBox.h"
31 #include "AliGenEventHeader.h"
35 //_____________________________________________________________________________
36 AliGenBox::AliGenBox()
43 // Default constructor
47 //_____________________________________________________________________________
48 AliGenBox::AliGenBox(Int_t npart)
55 // Standard constructor
58 fTitle = "Box particle generator";
61 //_____________________________________________________________________________
63 void AliGenBox::Generate()
66 // Generate one trigger
69 Float_t polar[3]= {0,0,0};
74 Double_t pmom, theta, phi, pt;
78 for (j=0;j<3;j++) origin[j]=fOrigin[j];
79 if(fVertexSmear==kPerEvent) {
81 for (j=0;j<3;j++) origin[j]=fVertex[j];
84 for(i=0;i<fNpart;i++) {
87 if (TestBit(kThetaRange)) {
88 theta = fThetaMin+random[0]*(fThetaMax-fThetaMin);
90 Float_t eta = fEtaMin+random[0]*(fEtaMax-fEtaMin);
91 theta = 2. * TMath::ATan(TMath::Exp(-eta));
95 if(TestBit(kMomentumRange)) {
96 pmom=fPMin+random[1]*(fPMax-fPMin);
97 pt=pmom*TMath::Sin(theta);
100 pt=fPtMin+random[1]*(fPtMax-fPtMin);
101 pmom=pt/TMath::Sin(theta);
104 phi=fPhiMin+random[2]*(fPhiMax-fPhiMin);
105 p[0] = pt*TMath::Cos(phi);
106 p[1] = pt*TMath::Sin(phi);
107 p[2] = pmom*TMath::Cos(theta);
109 if(fVertexSmear==kPerTrack) {
112 origin[j]=fOrigin[j]+fOsigma[j]*TMath::Cos(2*random[2*j]*TMath::Pi())*
113 TMath::Sqrt(-2*TMath::Log(random[2*j+1]));
116 PushTrack(fTrackIt,-1,fIpart,p,origin,polar,0,kPPrimary,nt);
119 AliGenEventHeader* header = new AliGenEventHeader("BOX");
120 header->SetPrimaryVertex(fVertex);
121 header->SetNProduced(fNpart);
123 // Passes header either to the container or to gAlice
125 fContainer->AddHeader(header);
127 gAlice->SetGenEventHeader(header);
131 //_____________________________________________________________________________
133 void AliGenBox::Init()
135 // Initialisation, check consistency of selected ranges
136 if(TestBit(kPtRange)&&TestBit(kMomentumRange))
137 Fatal("Init","You should not set the momentum range and the pt range!\n");
138 if((!TestBit(kPtRange))&&(!TestBit(kMomentumRange)))
139 Fatal("Init","You should set either the momentum or the pt range!\n");