| Geant4 Cross Reference |
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2 2
3 ========================================= 3 =========================================================
4 Geant4 - an Object-Oriented Toolkit for S 4 Geant4 - an Object-Oriented Toolkit for Simulation in HEP
5 ========================================= 5 =========================================================
6 6
7 ExUCN 7 ExUCN
8 ----- 8 -----
9 Peter Gumplinger 9 Peter Gumplinger
10 TRIUMF, Vancouver, Canada 10 TRIUMF, Vancouver, Canada
11 11
12 This example exhibits the functionality of UCN 12 This example exhibits the functionality of UCN physics
13 13
14 14
15 1- GEOMETRY DEFINITION 15 1- GEOMETRY DEFINITION
16 16
17 The geometry consists of a single hollow 17 The geometry consists of a single hollow pipe (cylinder)
18 placed in a world. 18 placed in a world.
19 19
20 Default World Size: G4Box - 1m x 1m x 100 20 Default World Size: G4Box - 1m x 1m x 100m
21 21
22 The pipe wall is made of G4_Ni while the 22 The pipe wall is made of G4_Ni while the world and, hence,
23 the inside of the pipe is made from G4_Ga 23 the inside of the pipe is made from G4_Galactic
24 24
25 The G4UCNMaterialPropertiesTable properti 25 The G4UCNMaterialPropertiesTable properties are:
26 26
27 "REFLECTIVITY" = 1 27 "REFLECTIVITY" = 1
28 "DIFFUSION" = 0.1 28 "DIFFUSION" = 0.1
29 "FERMIPOT" = 252.0 neV 29 "FERMIPOT" = 252.0 neV
30 "SPINFLIP"= 0. 30 "SPINFLIP"= 0.
31 "LOSS" = 12.5e-5 31 "LOSS" = 12.5e-5
32 "LOSSCS" = 0. 32 "LOSSCS" = 0.
33 "ABSCS"= 4.49 // 1/v loss cross-sectio 33 "ABSCS"= 4.49 // 1/v loss cross-section at room temp.
34 "SCATCS" = 18.5 // (incoherent) "elastic 34 "SCATCS" = 18.5 // (incoherent) "elastic" scattering cross-section
35 35
36 The MicroRoughnessParameters are: 36 The MicroRoughnessParameters are:
37 37
38 Roughness correlation length w = 30nm 38 Roughness correlation length w = 30nm
39 Surface roughness b = 1nm 39 Surface roughness b = 1nm
40 # of angles theta_i in the look-up tables 40 # of angles theta_i in the look-up tables: 180
41 # of energie bins in the look-up tables: 41 # of energie bins in the look-up tables: 1000
42 min. and max. values of theta_i: 0*degree 42 min. and max. values of theta_i: 0*degree and 90*degree
43 min. and max values of Energy: 1neV and 1 43 min. and max values of Energy: 1neV and 1000neV
44 # of angles theta_o in the look-up table 44 # of angles theta_o in the look-up table calculation: 15
45 # of angels phi_o in the look-up table 45 # of angels phi_o in the look-up table calculation: 15
46 angular cut: 0.01*degree 46 angular cut: 0.01*degree
47 47
48 The default step limits in the vacuum is 48 The default step limits in the vacuum is 1mm and maxTime is 100s
49 49
50 The simulation is in a G4UniformGravityFi 50 The simulation is in a G4UniformGravityField
51 51
52 2- PHYSICS LIST 52 2- PHYSICS LIST
53 53
54 The ExUCNPhysicsList defines only G4Neutro 54 The ExUCNPhysicsList defines only G4Neutron, G4Proton, G4Electron,
55 G4AntiNeutrinoE, G4MuonPlus, G4MuonMinus a 55 G4AntiNeutrinoE, G4MuonPlus, G4MuonMinus and G4GenericIon
56 56
57 Through ExUCNExtraPhysics the following pr 57 Through ExUCNExtraPhysics the following processes are instantiated:
58 58
59 G4StepLimiter 59 G4StepLimiter
60 G4UserSpecialCuts 60 G4UserSpecialCuts
61 61
62 and in ConstructUCN() 62 and in ConstructUCN()
63 63
64 G4UCNLoss 64 G4UCNLoss
65 G4UCNAbsorption 65 G4UCNAbsorption
66 G4UCNMultiScattering 66 G4UCNMultiScattering
67 67
68 3- AN EVENT : THE PRIMARY GENERATOR 68 3- AN EVENT : THE PRIMARY GENERATOR
69 69
70 The primary kinematic consists of a singl 70 The primary kinematic consists of a single ultra-cold neutron,
71 uniform between 1neV and 100neV, from the 71 uniform between 1neV and 100neV, from the origin and uniform
72 into 4pi solid angle. 72 into 4pi solid angle.
73 73
74 A RUN is a set of events. 74 A RUN is a set of events.
75 75
76 76
77 4- VISUALIZATION 77 4- VISUALIZATION
78 78
79 The Visualization Manager is set in the m 79 The Visualization Manager is set in the main() for interactive session.
80 The initialisation of the drawing is done 80 The initialisation of the drawing is done via the command
81 /control/execute vis.mac 81 /control/execute vis.mac
82 82
83 5- HOW TO START ? 83 5- HOW TO START ?
84 84
85 This example handles the program arguments 85 This example handles the program arguments in a new way.
86 It can be run with the following optional a 86 It can be run with the following optional arguments:
87 % ExUCN [-m macro ] [-u UIsession] [-t nThr 87 % ExUCN [-m macro ] [-u UIsession] [-t nThreads]
88 88
89 The -t option is available only in multi-th 89 The -t option is available only in multi-threading mode
90 and it allows the user to override the Gean 90 and it allows the user to override the Geant4 default number of
91 threads. The number of threads can be also 91 threads. The number of threads can be also set via G4FORCENUMBEROFTHREADS
92 environment variable which has the top prio 92 environment variable which has the top priority.
93 93
94 - execute ExUCN in 'batch' mode from m 94 - execute ExUCN in 'batch' mode from macro files e.g.
95 % ExUCN -m ExUCN.in > ExUCN.ou 95 % ExUCN -m ExUCN.in > ExUCN.out &
96 96
97 - execute ExUCN in 'interactive' mode 97 - execute ExUCN in 'interactive' mode with visualization e.g.
98 % ExUCN 98 % ExUCN
99 .... 99 ....
100 Idle> type your commands, for 100 Idle> type your commands, for example:
101 Idle> run/beamOn 1 101 Idle> run/beamOn 1
102 .... 102 ....
103 103
104 6- HISTOGRAMS 104 6- HISTOGRAMS
105 105
106 - no histograms for now 106 - no histograms for now