| Geant4 Cross Reference |
>> 1 $Id: README 78070 2013-12-03 11:29:49Z ihrivnac $
1 ---------------------------------------------- 2 -------------------------------------------------------------------
2 3
3 ========================================= 4 =========================================================
4 Geant4 - an Object-Oriented Toolkit for S 5 Geant4 - an Object-Oriented Toolkit for Simulation in HEP
5 ========================================= 6 =========================================================
6 7
7 ExUCN 8 ExUCN
8 ----- 9 -----
9 Peter Gumplinger 10 Peter Gumplinger
10 TRIUMF, Vancouver, Canada 11 TRIUMF, Vancouver, Canada
11 12
12 This example exhibits the functionality of UCN 13 This example exhibits the functionality of UCN physics
13 14
14 15
15 1- GEOMETRY DEFINITION 16 1- GEOMETRY DEFINITION
16 17
17 The geometry consists of a single hollow 18 The geometry consists of a single hollow pipe (cylinder)
18 placed in a world. 19 placed in a world.
19 20
20 Default World Size: G4Box - 1m x 1m x 100 21 Default World Size: G4Box - 1m x 1m x 100m
21 22
22 The pipe wall is made of G4_Ni while the 23 The pipe wall is made of G4_Ni while the world and, hence,
23 the inside of the pipe is made from G4_Ga 24 the inside of the pipe is made from G4_Galactic
24 25
25 The G4UCNMaterialPropertiesTable properti 26 The G4UCNMaterialPropertiesTable properties are:
26 27
27 "REFLECTIVITY" = 1 28 "REFLECTIVITY" = 1
28 "DIFFUSION" = 0.1 29 "DIFFUSION" = 0.1
29 "FERMIPOT" = 252.0 neV 30 "FERMIPOT" = 252.0 neV
30 "SPINFLIP"= 0. 31 "SPINFLIP"= 0.
31 "LOSS" = 12.5e-5 32 "LOSS" = 12.5e-5
32 "LOSSCS" = 0. 33 "LOSSCS" = 0.
33 "ABSCS"= 4.49 // 1/v loss cross-sectio 34 "ABSCS"= 4.49 // 1/v loss cross-section at room temp.
34 "SCATCS" = 18.5 // (incoherent) "elastic 35 "SCATCS" = 18.5 // (incoherent) "elastic" scattering cross-section
35 36
36 The MicroRoughnessParameters are: 37 The MicroRoughnessParameters are:
37 38
38 Roughness correlation length w = 30nm 39 Roughness correlation length w = 30nm
39 Surface roughness b = 1nm 40 Surface roughness b = 1nm
40 # of angles theta_i in the look-up tables 41 # of angles theta_i in the look-up tables: 180
41 # of energie bins in the look-up tables: 42 # of energie bins in the look-up tables: 1000
42 min. and max. values of theta_i: 0*degree 43 min. and max. values of theta_i: 0*degree and 90*degree
43 min. and max values of Energy: 1neV and 1 44 min. and max values of Energy: 1neV and 1000neV
44 # of angles theta_o in the look-up table 45 # of angles theta_o in the look-up table calculation: 15
45 # of angels phi_o in the look-up table 46 # of angels phi_o in the look-up table calculation: 15
46 angular cut: 0.01*degree 47 angular cut: 0.01*degree
47 48
48 The default step limits in the vacuum is 49 The default step limits in the vacuum is 1mm and maxTime is 100s
49 50
50 The simulation is in a G4UniformGravityFi 51 The simulation is in a G4UniformGravityField
51 52
52 2- PHYSICS LIST 53 2- PHYSICS LIST
53 54
54 The ExUCNPhysicsList defines only G4Neutro 55 The ExUCNPhysicsList defines only G4Neutron, G4Proton, G4Electron,
55 G4AntiNeutrinoE, G4MuonPlus, G4MuonMinus a 56 G4AntiNeutrinoE, G4MuonPlus, G4MuonMinus and G4GenericIon
56 57
57 Through ExUCNExtraPhysics the following pr 58 Through ExUCNExtraPhysics the following processes are instantiated:
58 59
59 G4StepLimiter 60 G4StepLimiter
60 G4UserSpecialCuts 61 G4UserSpecialCuts
61 62
62 and in ConstructUCN() 63 and in ConstructUCN()
63 64
64 G4UCNLoss 65 G4UCNLoss
65 G4UCNAbsorption 66 G4UCNAbsorption
66 G4UCNMultiScattering 67 G4UCNMultiScattering
67 68
68 3- AN EVENT : THE PRIMARY GENERATOR 69 3- AN EVENT : THE PRIMARY GENERATOR
69 70
70 The primary kinematic consists of a singl << 71 The primary kinematic consists of a single ultra-colde neutron
71 uniform between 1neV and 100neV, from the << 72 (uniform between 1neV and 100neV from the origin uniform into 4pi
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