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 //____________________________________________________________________
20 // Forward Multiplicity Detector based on Silicon wafers. This class
21 // contains the base procedures for the Forward Multiplicity detector
22 // Detector consists of 5 Si volumes covered pseudorapidity interval
25 // This class contains the detailed version of the FMD - that is, hits
26 // are produced during simulation.
28 // The actual code is done by various separate classes. Below is
29 // diagram showing the relationship between the various FMD classes
30 // that handles the geometry
33 // +----------+ +----------+
34 // | AliFMDv1 | | AliFMDv1 |
35 // +----------+ +----------+
37 // +----+--------------+
39 // | +------------+ 1 +---------------+
40 // | +- | AliFMDRing |<>--| AliFMDPolygon |
41 // V 2 | +------------+ +---------------+
44 // +--------+<>--+ V 1..2
45 // 3 | +-------------------+
46 // +-| AliFMDSubDetector |
47 // +-------------------+
50 // +-------------+-------------+
52 // +---------+ +---------+ +---------+
53 // | AliFMD1 | | AliFMD2 | | AliFMD3 |
54 // +---------+ +---------+ +---------+
57 // See also the class AliFMD for a more detailed explanation of the
59 #ifndef ROOT_TVirtualMC
60 # include <TVirtualMC.h>
63 # include "AliFMDv1.h"
75 //____________________________________________________________________
79 //____________________________________________________________________
81 AliFMDv1::StepManager()
84 // Called for every step in the Forward Multiplicity Detector
86 // The procedure is as follows:
88 // - IF NOT track is alive THEN RETURN ENDIF
89 // - IF NOT particle is charged THEN RETURN ENDIF
90 // - IF NOT volume name is "STRI" or "STRO" THEN RETURN ENDIF
91 // - Get strip number (volume copy # minus 1)
92 // - Get phi division number (mother volume copy #)
93 // - Get module number (grand-mother volume copy #)
94 // - section # = 2 * module # + phi division # - 1
95 // - Get ring Id from volume name
96 // - Get detector # from grand-grand-grand-mother volume name
97 // - Get pointer to sub-detector object.
98 // - Get track position
99 // - IF track is entering volume AND track is inside real shape THEN
100 // - Reset energy deposited
101 // - Get track momentum
102 // - Get particle ID #
104 // - IF track is inside volume AND inside real shape THEN
105 /// - Update energy deposited
107 // - IF track is inside real shape AND (track is leaving volume,
108 // or it died, or it is stopped THEN
113 // DebugGuard guard("AliFMDv1::StepManager");
114 AliDebug(10, "AliFMDv1::StepManager");
117 // If the track is gone, return
118 if (!gMC->IsTrackAlive()) return;
120 // Only process charged particles
121 if(TMath::Abs(gMC->TrackCharge()) <= 0) return;
123 // TString vol(gMC->CurrentVolName());
124 // std::cout << "Is inside " << vol << " ... " << std::endl;
125 // Only do stuff is the track is in one of the strips.
126 // TString vol(gMC->CurrentVolName());
127 // if (!vol.Contains("STR")) return;
129 Int_t volumeId = gMC->CurrentVolID(copy);
130 // The ring ID is encoded in the volume name
132 if (volumeId == fInner->GetStripId()) ring = 'I';
133 else if (volumeId == fOuter->GetStripId()) ring = 'O';
136 // Get the strip number. Note, that GEANT numbers divisions from 1,
137 // so we subtract one
138 Int_t strip = copy - 1;
140 // Get the phi division of the module
141 Int_t phiDiv; // * The phi division number (1 or 2)
142 gMC->CurrentVolOffID(1, phiDiv); // in the module
144 // Active volume number - not used.
146 // gMC->CurrentVolOffID(2, active);
148 // Get the module number in the ring.
150 gMC->CurrentVolOffID(3, module);
152 // Ring copy number - the same as the detector number - not used
153 // Int_t ringCopy; // * Ring copy number
154 // gMC->CurrentVolOffID(4, ringCopy); // Same as detector number
156 // Get the detector number from the path name
157 Int_t detector = Int_t((gMC->CurrentVolOffName(5)[3]) - 48);
159 // The sector number, calculated from module and phi division #
160 Int_t sector = 2 * module + phiDiv - 1;
163 // Get a pointer to the sub detector structure
164 AliFMDSubDetector* det = 0;
166 case 1: det = fFMD1; break;
167 case 2: det = fFMD2; break;
168 case 3: det = fFMD3; break;
172 // Get the current track position
174 gMC->TrackPosition(v);
175 // Check that the track is actually within the active area
176 Bool_t isWithin = det->CheckHit(ring, module, v.X(), v.Y());
177 Bool_t entering = gMC->IsTrackEntering() && isWithin;
178 Bool_t inside = gMC->IsTrackInside() && isWithin;
179 Bool_t out = (gMC->IsTrackExiting()
180 || gMC->IsTrackDisappeared()
181 || gMC->IsTrackStop()
183 // Reset the energy deposition for this track, and update some of
188 // Get production vertex and momentum of the track
190 gMC->TrackMomentum(fCurrentP);
191 fCurrentPdg = gMC->IdFromPDG(gMC->TrackPid());
194 // fAnalyser->Update(detector, ring, isWithin, v.X(), v.Y());
197 // If the track is inside, then update the energy deposition
198 if (inside && fCurrentDeltaE >= 0)
199 fCurrentDeltaE += 1000 * gMC->Edep();
201 // The track exits the volume, or it disappeared in the volume, or
202 // the track is stopped because it no longer fulfills the cuts
203 // defined, then we create a hit.
204 if (out && fCurrentDeltaE >= 0) {
205 fCurrentDeltaE += 1000 * gMC->Edep();
207 AddHit(gAlice->GetMCApp()->GetCurrentTrackNumber(),
208 detector, ring, sector, strip,
209 fCurrentV.X(), fCurrentV.Y(), fCurrentV.Z(),
210 fCurrentP.X(), fCurrentP.Y(), fCurrentP.Z(),
211 fCurrentDeltaE, fCurrentPdg, fCurrentV.T());
215 //___________________________________________________________________