| Geant4 Cross Reference |
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4 Geant4 - an Object-Oriented Toolkit for S
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6
7 electronScattering
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9
10 Electron scattering benchmark (T. O'Shea and
11
12 1- GEOMETRY DEFINITION
13
14 The geometry is described in the enclosed doc
15
16 A "World" volume contains a "Frame" made of A
17 The Frame contains : ExitWindow, ScatterFoil,
18 The Bag contains a Gas volume, which contains
19 The Scoring plane is the end-plane of the Fra
20
21 The default geometry is constructed in Detect
22 The parameters of the ScatterFoil (material a
23 via 2 UI commands : see the macro scatter.mac
24
25 2- PHYSICS LIST
26
27 Physics lists can be local (eg. in this examp
28 physics_lists subdirectory.
29
30 Local physics lists:
31 - "local" standard EM physics with current '
32 these options are explicited i
33 - "standardSS" standard EM physics with singl
34 instead of multiple scattering
35
36 From geant4/source/physics_lists/builders:
37 - "emstandard_opt0" recommended standard EM
38 - "emstandard_opt1" best CPU performance sta
39 - "emstandard_opt2" alternative models
40 - "emstandard_opt3" current state of art for
41 analog to "local"above
42
43 Physics lists and options can be (re)set with
44
45 Please, notice that options set through G4EmP
46 for all particle types. In G4 builders, it is
47 particle type.
48
49
50 3- PRIMARY GENERATOR : mono-enegetic pencil b
51
52 The primary kinematic consists of a single pa
53 perpendicular to the input face (ExitWindow).
54 energy are set in the PrimaryGeneratorAction
55 the G4 build-in commands of ParticleGun class
56 (see the macros provided with this example)
57
58 The incident beam has a Gaussian-shaped spati
59 Gaussian can be define with an UI command bui
60
61 4- VISUALIZATION
62
63 The Visualization Manager is set in the main(
64 The initialisation of the drawing is done via
65 In interactive session:
66 PreInit or Idle > /control/execute vis.mac
67
68 The example has a default view which is a lon
69
70 The tracks are drawn at the end of event, and
71 Optionaly one can choose to draw all particle
72 This command is defined in EventActionMesseng
73
74 5- TRACKING
75
76 One can limit 'by hand' the step lenght of t
77 this limitation is implemented as a 'full' pr
78 Messenger. The 'StepMax process' is registere
79
80 6- DETECTOR RESPONSE
81
82 At the end of a run, from the histogram(s), o
83 physics quantities, via the histograms define
84
85 An ascii file corresponding to histo 4 (see b
86
87
88 7- List of the built-in histograms
89 ----------------------------------
90
91 The test contains 4 built-in 1D histograms, w
92 G4AnalysisManager class and its Messenger. Th
93 with the command :
94 /analysis/h1/set id nbBins valMin valMax uni
95 where unit is the desired unit for the histo
96 (see the macros xxxx.mac).
97
98 1 "(charged particles): projected angle at S
99 2 "(charged particles): dN/dS at Scoring pla
100 3 "(charged particles): d(N/cost)/dS at Scor
101 4 "(charged particles): normalized d(N/cost)
102 5 "(charged particles); scatteri
103 6 "(charged particles); measured
104
105 The histograms can be viewed using ROOT or PA
106
107 One can control the name and format of the hi
108 /analysis/setFileName name (default nrccBen
109 It is possible to choose the format of the hi
110 xml, csv, by using namespace in HistoManager.
111 It is also possible to print selected histogr
112 /analysis/h1/setAscii id
113 All selected histos will be written on a file
114
115
116 8- HOW TO START ?
117
118 - execute electronScattering in 'batch' mode
119 % electronScattering myMacro.mac
120
121 - execute electronScattering in 'interactive'
122 % electronScattering
123 Then type your commands, for instance :
124 Idle> control/execute vis.mac
125 Idle> run/beamOn 5
126 ....