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 **************************************************************************/
18 Revision 1.8 2002/02/08 16:50:50 morsch
19 Add name and title in constructor.
21 Revision 1.7 2001/07/27 17:09:35 morsch
22 Use local SetTrack, KeepTrack and SetHighWaterMark methods
23 to delegate either to local stack or to stack owned by AliRun.
24 (Piotr Skowronski, A.M.)
26 Revision 1.6 2000/12/21 16:24:06 morsch
27 Coding convention clean-up
29 Revision 1.5 2000/12/06 15:11:38 morsch
30 Correct double declared data members.
32 Revision 1.4 2000/11/30 07:12:50 alibrary
33 Introducing new Rndm and QA classes
35 Revision 1.3 2000/10/02 21:28:06 fca
36 Removal of useless dependecies via forward declarations
38 Revision 1.2 2000/06/09 20:37:51 morsch
39 All coding rule violations except RS3 corrected
41 Revision 1.1 2000/02/23 16:25:14 morsch
42 First commit of this file
46 // As AliGenScan, generation of particles on a 3-dim grid
47 // but here double hits with a predefined distance are generated.
48 // The second particle is generated at a constant distance but with random phi.
49 // Generator can be used to evaluate double hit resolutions.
50 // Author: andreas.morsch@cern.ch
52 #include "AliGenDoubleScan.h"
55 ClassImp(AliGenDoubleScan)
57 AliGenDoubleScan::AliGenDoubleScan()
62 AliGenDoubleScan::AliGenDoubleScan(Int_t npart)
66 fName = "Double Scan";
67 fTitle= "Particle Generator for two correlated particles on a grid";
70 //____________________________________________________________
71 AliGenDoubleScan::~AliGenDoubleScan()
76 //____________________________________________________________
77 void AliGenDoubleScan::Generate()
80 // Generate one trigger
83 Float_t polar[3]= {0,0,0};
88 Float_t pmom, theta, phi;
95 dx=(fXCmax-fXCmin)/fNx;
101 dy=(fYCmax-fYCmin)/fNy;
107 dz=(fZmax-fZmin)/fNz;
111 for (Int_t ix=0; ix<fNx; ix++) {
112 for (Int_t iy=0; iy<fNy; iy++) {
113 for (Int_t iz=0; iz<fNz; iz++){
115 origin[0]=fXCmin+ix*dx+2*(random[0]-0.5)*fOsigma[0];
116 origin[1]=fYCmin+iy*dy+2*(random[1]-0.5)*fOsigma[1];
117 origin[2]=fZmin+iz*dz+2*(random[2]-0.5)*fOsigma[2];
118 pmom=fPMin+random[3]*(fPMax-fPMin);
119 theta=fThetaMin+random[4]*(fThetaMax-fThetaMin);
120 phi=fPhiMin+random[5]*(fPhiMax-fPhiMin);
121 p[0] = pmom*TMath::Cos(phi)*TMath::Sin(theta);
122 p[1] = pmom*TMath::Sin(phi)*TMath::Sin(theta);
123 p[2] = pmom*TMath::Cos(theta);
124 SetTrack(fTrackIt,-1,fIpart,p,origin,polar,0,kPPrimary,nt);
126 // Generate 2nd particle at distance fDistance from the first
129 Float_t phi2=2.*TMath::Pi()*random[0];
130 Float_t dx =fDistance*TMath::Sin(phi2);
131 Float_t dy =fDistance*TMath::Cos(phi2);
132 origin[0]=origin[0]+dx;
133 origin[1]=origin[1]+dy;
134 pmom=fPMin+random[1]*(fPMax-fPMin);
135 theta=fThetaMin+random[2]*(fThetaMax-fThetaMin);
136 phi=fPhiMin+random[3]*(fPhiMax-fPhiMin);
137 p[0] = pmom*TMath::Cos(phi)*TMath::Sin(theta);
138 p[1] = pmom*TMath::Sin(phi)*TMath::Sin(theta);
139 p[2] = pmom*TMath::Cos(theta);
140 SetTrack(fTrackIt,-1,fIpart,p,origin,polar,0,kPPrimary,nt);