| Geant4 Cross Reference |
1
2 =========================================
3 Geant4 - an Object-Oriented Toolkit for S
4 =========================================
5
6 Hadr03
7 ------
8
9 How to compute total cross section from the
10 mean free path ( see below, item Physics).
11 How to identify nuclear reactions.
12 How to plot energy spectrum of secondary pa
13
14 1- GEOMETRY DEFINITION
15
16 It is a single box representing a 'semi inf
17 Two parameters define the geometry :
18 - the material of the box,
19 - the (full) size of the box.
20
21 The default geometry (10 m of molybdenum) i
22 but the above parameters can be changed int
23 in DetectorMessenger.
24
25 2- PHYSICS LIST
26
27 The PhysicsList contains builders for hadro
28 Predefined G4 PhysicsConstructors or 'local
29 (see geant4/source/physics_lists or example
30
31 In order not to introduce 'artificial' cons
32 electromagnetic processes are not registere
33 loss.
34
35 Several hadronic physics options are contro
36 To select them, see Hadr03.cc.
37
38 3- AN EVENT : THE PRIMARY GENERATOR
39
40 The primary kinematic consists of a single
41 of the box. The type of the particle and it
42 PrimaryGeneratorAction (neutron 1 MeV), and
43 build-in commands of ParticleGun class (see
44 this example).
45
46 4- PHYSICS
47
48 An event is killed at the first interaction
49 The absorption length, also called mean fre
50 the mean value of the track length of the i
51 This is why the medium must be 'infinite' :
52 occurs at any events.
53
54 The result is compared with the 'input' val
55 given by G4HadronicProcessStore and used by
56
57 The list of nuclear reactions that occured
58 (the number of gamma of deexcitation is not
59
60 Then, comes the total list of generated par
61 The energy spectrum of the scattered partic
62 secondaries are plotted (see SteppingAction
63
64 Momentum conservation is checked as :
65 momentum balance = modulus(P_out - P_in)
66
67 A set of macros defining various run condit
68 The processes can be actived/inactived in o
69 individually.
70
71 5- HISTOGRAMS
72
73 The test contains 12 built-in 1D histograms
74 G4AnalysisManager and its Messenger. The hi
75 activated with the command :
76 /analysis/h1/set id nbBins valMin valMax u
77 where unit is the desired unit for the hist
78 (see the macros xxxx.mac).
79
80 1 "kinetic energy of scattered pri
81 2 "kinetic energy of gamma"
82 3 "kinetic energy of e-"
83 4 "kinetic energy of neutrons"
84 5 "kinetic energy of protons"
85 6 "kinetic energy of deuterons"
86 7 "kinetic energy of alphas"
87 8 "kinetic energy of nuclei"
88 9 "kinetic energy of mesons"
89 10 "kinetic energy of baryons"
90 11 "Q = Ekin out - Ekin in"
91 12 "Pbalance = mag(P_out - P_in)"
92 13 "atomic mass of nuclei"
93
94 The histograms are managed by the HistoMana
95 The histos can be individually activated wi
96 /analysis/h1/set id nbBins valMin valMax u
97 where unit is the desired unit for the hist
98
99 One can control the name of the histograms
100 /analysis/setFileName name (default Hadr0
101
102 It is possible to choose the format of the
103 xml, csv, by using namespace in HistoManage
104
105 It is also possible to print selected histo
106 /analysis/h1/setAscii id
107 All selected histos will be written on a fi
108
109 6- VISUALIZATION
110
111 The Visualization Manager is set in the mai
112 The initialisation of the drawing is done v
113 /vis/... in the macro vis.mac. To get visua
114 > /control/execute vis.mac
115
116 The detector has a default view which is a
117 The tracks are drawn at the end of event, a
118
119 7- HOW TO START ?
120
121 Execute Hadr03 in 'batch' mode from macro f
122 % Hadr03 inelastic.mac
123
124 Execute Hadr03 in 'interactive mode' with v
125 % Hadr03
126 Idle> control/execute vis.mac
127 ....
128 Idle> type your commands
129 ....
130 Idle> exit
131
132 Macros provided in this example:
133 - hadr03.in: macro used in Geant4 testing
134 - Au196.mac: neutron (1 MeV) on Au195
135 - elastic.mac: proton (10 MeV) on Mo100. Ela
136 - fusion.mac: deuteron (400 keV) on tritium
137 - gamma.mac: gamma (10 MeV) on Au196
138 - inelastic.mac: proton (10 MaV) on Mo98. In
139 - ion.mac: Li7 (140 MeV) on Be9
140 - nCapture.mac: neutron (1 eV) on Boron. Cap
141 - nFission.mac: neutron (1 eV) on U235. Fis
142 - neutron.mac: neutron (1 MeV) on Boron
143
144 Macros to be run interactively:
145 - debug.mac: proton (10 MeV) on Boron
146 - vis.mac: To activate visualization