| Geant4 Cross Reference |
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4 Geant4 - an Object-Oriented Toolkit for S
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6
7 TestEm6
8 -------
9 This example is intended to test the proc
10 to a pair of muons and annihilation of po
11 electrons to a pair of muons.
12
13 1- GEOMETRY DEFINITION
14
15 The geometry consists of a single block o
16
17 Two parameters define the geometry :
18 - the material of the box,
19 - the (full) size of the box.
20 The default is 500 m of iron.
21
22 In addition a transverse uniform magnetic
23
24 The default geometry is constructed in De
25 but all of the above parameters can be ch
26 the commands defined in the DetectorMesse
27
28 2- PHYSICS LIST
29
30 Physics Lists are based on modular design
31 instantiated:
32 1. Transportation
33 2. EM physics
34 3. Decays
35 4. StepMax - for step limitation
36
37 The electromagnetic physics is chosen fro
38 physics constructors in the physics_list
39
40 Cross sections can be enhanced (see below
41
42 3- AN EVENT : THE PRIMARY GENERATOR
43
44 The primary kinematic consists of a singl
45 block perpendicular to the input face. Th
46 and its energy are set in the PrimaryGene
47 changed via the G4 build-in commands of G
48 the macros provided with this example).
49 The default is a Gamma of 100 TeV.
50
51 In addition one can choose randomly the i
52 particle. The corresponding interactive c
53 PrimaryGeneratorMessenger class.
54
55 A RUN is a set of events.
56
57 4- VISUALIZATION
58
59 The Visualization Manager is set in the m
60 The initialisation of the drawing is done
61 > /control/execute vis.mac
62
63 The detector has a default view which is
64
65 The tracks are drawn at the end of event,
66 Optionally one can choose to draw all par
67 or none. This command is defined in Event
68
69 5- PHYSICS DEMO
70
71 The particle's type and the physics proce
72 in this example are set in PhysicsList cl
73
74 In addition a build-in interactive comman
75 allows to activate/inactivate the process
76
77 The threshold for producing secondaries c
78 eg: /run/particle/setCut 100 micrometer
79 /run/initialize
80
81 To visualize the GammaConversionToMuons :
82 /control/execute run01.mac
83 /control/execute vis.mac
84 /run/beamOn
85
86 To visualize the AnnihiToMuPair :
87 /control/execute run11.mac
88 /control/execute vis.mac
89 /run/beamOn
90
91 Other macros:
92 - run02.mac: the final state of the Gamma
93 - run12.mac: test on carbon target with b
94
95 6- HOW TO START ?
96
97 - execute Test in 'batch' mode from macr
98 % TestEm6 run01.mac
99
100 - execute Test in 'interactive mode' wit
101 % TestEm6
102 ....
103 Idle> type your commands
104 ....
105 Idle> exit
106
107 7- HOW TO INCREASE STATISTICS ON gamma -> mu+
108
109 The processes of gamma -> mu+mu- and e+e
110 have a low cross section but can be impor
111 for leakage through thick absorbers and c
112 Straight forward simulation will be quite
113 To make the processes more visible, the c
114 artificially increased by some factor (he
115 using the commands (only effective after
116
117 /testem/phys/SetGammaToMuPairFac 1000
118 /testem/phys/SetAnnihiToMuPairFac 1000
119
120
121 8- HISTOGRAMS
122
123 Testem6 produces 6 histograms, h1 - h6, whic
124 the final state of the GammaConversionToMuon
125 with run02.mac and can be displayed with the
126
127 The remaining histograms h7 - h16 show vario
128 of eeToHadr/eeToMu, see their definitions in
129
130 By default the histograms are saved as teste
131
132 The format of the histogram file can be : ro
133 by selecting the analysis manager default fi