| Geant4 Cross Reference |
1 ------------------------------Advanced Example 1 ------------------------------Advanced Example--------------------------------- README FILE
2 2
3 Note: Due to the importation of data files dur 3 Note: Due to the importation of data files during the initialisation stage of
4 Geant4, load-time may be in excess of 5 minute 4 Geant4, load-time may be in excess of 5 minutes.
5 5
6 UNDERGROUND PHYSICS 6 UNDERGROUND PHYSICS
7 7
8 An example of a underground dark matter experi 8 An example of a underground dark matter experiment.
9 9
10 Please see the UserRequirements.txt and relate 10 Please see the UserRequirements.txt and related web-pages referred to
11 at the end of that document. 11 at the end of that document.
12 12
13 Over-view: 13 Over-view:
14 A single liquid xenon cell is simulated within 14 A single liquid xenon cell is simulated within Geant4 and the scintillation
15 light produced from interactions from various 15 light produced from interactions from various calibration species is recorded
16 as PhotoMultiplier hits. The output is then w 16 as PhotoMultiplier hits. The output is then written to an ASCII file for
17 future off-line analysis. 17 future off-line analysis.
18 18
19 Geometry: 19 Geometry:
20 Experimental set-up: 20 Experimental set-up:
21 21
22 G4double worldWidth = 470.0*cm + 2.*wallThi 22 G4double worldWidth = 470.0*cm + 2.*wallThick; // "x"
23 G4double worldLength = 690.0*cm + 2.*wallThi 23 G4double worldLength = 690.0*cm + 2.*wallThick; // "y"
24 G4double worldHeight = 280.0*cm + 2.*wallThi 24 G4double worldHeight = 280.0*cm + 2.*wallThick; // "z"
25 25
26 26
27 27
28 A "cavern" of dimensions 5.18m x 7.38m x 3.28m 28 A "cavern" of dimensions 5.18m x 7.38m x 3.28m with concrete walls is defined
29 as the World Volume. A laboratory geometry is 29 as the World Volume. A laboratory geometry is incorporated included desks,
30 cupboards, door and windows. For ease this is 30 cupboards, door and windows. For ease this is included in a separate ".icc"
31 file which can be removed should the code seem 31 file which can be removed should the code seem cumbersome. In the centre of
32 the cavern a steel vacuum vessel containing li 32 the cavern a steel vacuum vessel containing liquid and gaseous xenon is placed.
33 The internal construction of the vessel accura 33 The internal construction of the vessel accurately reproduces an existing
34 prototype Dark Matter detector which allows ex 34 prototype Dark Matter detector which allows experimental comparison. The active
35 detector volume is defined by a series of meta 35 detector volume is defined by a series of metal rings, complemented by
36 a cover mirror and a PMT immersed in the liqui 36 a cover mirror and a PMT immersed in the liquid. Two grids and a
37 thermalising copper shield are also incorporat 37 thermalising copper shield are also incorporated. The liquid/gas
38 interface is located 6mm away from the mirror 38 interface is located 6mm away from the mirror surface. A Am241
39 calibration source is suspended from one of th 39 calibration source is suspended from one of the grids in the liquid
40 phase, above the PMT. 40 phase, above the PMT.
41 41
42 XXX================XXX mirror 42 XXX================XXX mirror
43 XXX________________XXX gas phase 43 XXX________________XXX gas phase
44 XXX XXX 44 XXX XXX
45 XXX XXX liquid phase 45 XXX XXX liquid phase
46 XXX XXX 46 XXX XXX
47 XXX.......U........XXX grid + calibrator 47 XXX.......U........XXX grid + calibrator
48 XXX................XXX grid 48 XXX................XXX grid
49 XXX| |XXX 49 XXX| |XXX
50 | ___------___ | 50 | ___------___ |
51 || PMT || 51 || PMT ||
52 || || 52 || ||
53 53
54 54
55 Hits Output (file "hits.out"): 55 Hits Output (file "hits.out"):
56 An ASCII file containing the following informa 56 An ASCII file containing the following information:
57 Evt # : event number 57 Evt # : event number
58 Etot, MeV : energy deposited in liqui 58 Etot, MeV : energy deposited in liquid xenon
59 LXe hits : number of hits in liquid 59 LXe hits : number of hits in liquid xenon
60 LXeTime, ns : time of first hit in liqu 60 LXeTime, ns : time of first hit in liquid xenon
61 PMT hits : number of hits in PMT (ph 61 PMT hits : number of hits in PMT (photocathode)
62 PmtTime, ns : average PMT hit time rela 62 PmtTime, ns : average PMT hit time relative to LXeTime
63 First hit : first particle to hit liq 63 First hit : first particle to hit liquid xenon
64 Flags : particles contributing to 64 Flags : particles contributing to energy deposition
65 Seeds : the initial seed values for g 65 Seeds : the initial seed values for given hit events
66 66
67 Note: 67 Note:
68 68
69 The time information PmtTime is erroneous 69 The time information PmtTime is erroneous when forcing nuclear
70 decay with the RadioactiveDecay module du 70 decay with the RadioactiveDecay module due to the precision
71 required to detect nanosecond scintillati 71 required to detect nanosecond scintillation times on a global
72 time of 432 years (in the case of 241Am d 72 time of 432 years (in the case of 241Am decay).
73 73
74 74
75 Pmt Output (file "pmt.out"): 75 Pmt Output (file "pmt.out"):
76 Photon hit positions within the PMT face (over 76 Photon hit positions within the PMT face (overwritten every event):
77 "Hit# X, mm Y, mm Z, mm" 77 "Hit# X, mm Y, mm Z, mm"
78 78
79 79
80 To Run: 80 To Run:
81 Either run the macro files interactively or in 81 Either run the macro files interactively or in batch with the command
82 DMX macro_name.mac. 82 DMX macro_name.mac.
83 83
84 84
85 Macros: 85 Macros:
86 86
87 initInter.mac 87 initInter.mac
88 Initialisation macro for interactive mode. 88 Initialisation macro for interactive mode.
89 89
90 gamma.mac 90 gamma.mac
91 Shoots one 60 keV gamma upwards from the ca 91 Shoots one 60 keV gamma upwards from the calibrator and traces the
92 scintillation light produced in LXe to the 92 scintillation light produced in LXe to the PMT. All tracks are drawn
93 with custom colours. PMT hits in photocatho 93 with custom colours. PMT hits in photocathode are also shown. Event
94 summary is writen to file "hits.out". 94 summary is writen to file "hits.out".
95 95
96 gamma_1000.mac 96 gamma_1000.mac
97 Similar to above, but 1000 gammas are emmit 97 Similar to above, but 1000 gammas are emmited isotropically from the
98 source. No hits or tracks are draw, and the 98 source. No hits or tracks are draw, and the verbosity is reduced.
99 99
100 alpha.mac 100 alpha.mac
101 Shoots one 5.486 MeV alpha particle upwards 101 Shoots one 5.486 MeV alpha particle upwards from the calibrator and
102 traces the scintillation light to the PMT. 102 traces the scintillation light to the PMT. All tracks except
103 optical photons are drawn. Event summary is 103 optical photons are drawn. Event summary is written to file
104 "hits.out" and PMT hits to file "pmt.out". 104 "hits.out" and PMT hits to file "pmt.out".
105 105
106 alpha_1000.mac 106 alpha_1000.mac
107 Similar to above, but 1000 alphas are emmit 107 Similar to above, but 1000 alphas are emmited isotropically from the
108 source. No tracks are stored, and the verbo 108 source. No tracks are stored, and the verbosity is reduced. Event
109 summary is written to file "hits.out", PMT 109 summary is written to file "hits.out", PMT hits are not written out.
110 110
111 neutron.mac 111 neutron.mac
112 Shoots one 2.48 MeV neutron inside the room 112 Shoots one 2.48 MeV neutron inside the room aimed at the detector.
113 All tracks except scintillation photons are 113 All tracks except scintillation photons are drawn (custom colours).
114 Gammas are not killed at the concrete wall. 114 Gammas are not killed at the concrete wall. Event summery is written
115 to file "hits.out". 115 to file "hits.out".
116 116
117 ambe_spectrum.mac 117 ambe_spectrum.mac
118 Produces a spectrum of neutrons according t 118 Produces a spectrum of neutrons according to an approximation of a Am/Be
119 neutron source. However, this uses the GPS 119 neutron source. However, this uses the GPS and therefore will only work
120 after compilation with the DMXENV_GPS_USE e 120 after compilation with the DMXENV_GPS_USE environment variable (see below)
121 121
122 122
123 sourceAm241.mac 123 sourceAm241.mac
124 Forces the decay of 241Am nuclei in the cal 124 Forces the decay of 241Am nuclei in the calibrator and tracks the
125 resulting particles (237Np + alpha + gamma 125 resulting particles (237Np + alpha + gamma from 237Np
126 de-excitation). All tracks are drawn except 126 de-excitation). All tracks are drawn except scintillation photons.
127 Event summery is written to file "hits.out" 127 Event summery is written to file "hits.out".
128 -> To be added for a future release 128 -> To be added for a future release
129 129
130 130
131 sourceAm241_1000.mac 131 sourceAm241_1000.mac
132 Similar to above but for 1000 events. No tr 132 Similar to above but for 1000 events. No tracks are stored.
133 -> To be added for a future release 133 -> To be added for a future release
134 134
135 135
136 Note: 136 Note:
137 The following environment variables need to be 137 The following environment variables need to be set:
138 G4RADIOACTIVEDATA : points to Radioactive 138 G4RADIOACTIVEDATA : points to Radioactive Decay Data files
139 G4LEDATA : points to low energy 139 G4LEDATA : points to low energy data base
140 G4LEVELGAMMADATA : points to PhotoEvapor 140 G4LEVELGAMMADATA : points to PhotoEvaporation data
141 NeutronHPCrossSections : points to neutron dat 141 NeutronHPCrossSections : points to neutron data files
142 142
143 In addition if you require to use the full Gen 143 In addition if you require to use the full General Particle Source then the
144 variable DMXENV_GPS_USE can be set. The DMX g 144 variable DMXENV_GPS_USE can be set. The DMX gun is still included in order to
145 allow forward compatibility should the GPS cha 145 allow forward compatibility should the GPS change.
146 146
147 147
148 ANALYSIS: 148 ANALYSIS:
149 149
150 The program should produce ROOT-based histogra 150 The program should produce ROOT-based histogram files. It is possible to
151 produce the output in XML-compliant format by << 151 produce the output in XML-compliant format by editing the file
>> 152 include/DMXAnalysisManager.hh
>> 153 and by commenting out
>> 154 #include "g4root.hh"
>> 155 and uncommenting
>> 156 #include "g4xml.hh"
152 157
153 SEEDS: 158 SEEDS:
154 159
155 The seeds of event hits are stored in the hit 160 The seeds of event hits are stored in the hit record file. These can be used
156 to repeat events for visualisation, test crash 161 to repeat events for visualisation, test crashes/idiosyncracies:
157 162
158 /random/setDirectoryName ./seeds 163 /random/setDirectoryName ./seeds
159 /random/resetEngineFrom currentEvent.rndm 164 /random/resetEngineFrom currentEvent.rndm
160 /random/saveThisEvent 165 /random/saveThisEvent
161 /random/setSavingFlag 166 /random/setSavingFlag
162 167
163 The file currentEvent.rndm should contain the 168 The file currentEvent.rndm should contain the two seeds which were outputed in
164 the scintHit file. 169 the scintHit file.
165 170
166 ERRORS: 171 ERRORS:
167 172
168 When running interactively the following error 173 When running interactively the following error will be shown:
169 174
170 BooleanProcessor::caseIE : unimplemented case 175 BooleanProcessor::caseIE : unimplemented case
171 BooleanProcessor::caseIE : unimplemented case 176 BooleanProcessor::caseIE : unimplemented case
172 BooleanProcessor::caseIE : unimplemented case 177 BooleanProcessor::caseIE : unimplemented case
173 BooleanProcessor::caseIE : unimplemented case 178 BooleanProcessor::caseIE : unimplemented case
174 BooleanProcessor::caseIE : unimplemented case 179 BooleanProcessor::caseIE : unimplemented case
175 BooleanProcessor::caseIE : unimplemented case 180 BooleanProcessor::caseIE : unimplemented case
176 BooleanProcessor: boolean operation failed 181 BooleanProcessor: boolean operation failed
177 BooleanProcessor::caseIE : unimplemented case 182 BooleanProcessor::caseIE : unimplemented case
178 BooleanProcessor::caseIE : unimplemented case 183 BooleanProcessor::caseIE : unimplemented case
179 BooleanProcessor::caseIE : unimplemented case 184 BooleanProcessor::caseIE : unimplemented case
180 BooleanProcessor::caseIE : unimplemented case 185 BooleanProcessor::caseIE : unimplemented case
181 BooleanProcessor: boolean operation failed 186 BooleanProcessor: boolean operation failed
182 187
183 This is a "feature" of the visualisation of bo 188 This is a "feature" of the visualisation of boolean volumes, but does not
184 affect functionality/performance so can be ign 189 affect functionality/performance so can be ignored.
185 190
186 NB: 191 NB:
187 If using explicit libraries (?) i.e. non-share 192 If using explicit libraries (?) i.e. non-shared then compilation time with
188 neutrons in physics list is very long (>5 minu 193 neutrons in physics list is very long (>5 minutes) - check this.............
189 It is more efficient to use shared libraries t 194 It is more efficient to use shared libraries that are loaded at run-time with
190 increased initialisation time (at run-time). 195 increased initialisation time (at run-time).
191 196
192 Also if using shared libraries the load time a 197 Also if using shared libraries the load time at run-time may be several minutes
193 - this is partially due to the neutron impleme 198 - this is partially due to the neutron implementation requires full data sets
194 for each isotope being specified. 199 for each isotope being specified.
195 200
196 201
197 -------------------------------------- 202 --------------------------------------
198 203
199 If running on Redhat 7.0 or above set G4SYSTEM 204 If running on Redhat 7.0 or above set G4SYSTEM to Linux-g++, alternatively you
200 can install backward compatibility to egcs, ho 205 can install backward compatibility to egcs, however, requires
201 config/sys/Linux-egcs.gmk to be altered so tha 206 config/sys/Linux-egcs.gmk to be altered so that CXX is set to kgcc
202 (compared to g++ in original file) 207 (compared to g++ in original file)
203 208
204 -------------------------------------- 209 --------------------------------------
205 210
206 211
207 Alex Howard, 29/11/01 212 Alex Howard, 29/11/01
208 updated 18/06/02 213 updated 18/06/02
209 214