| 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 amsEcal 7 amsEcal
8 ------- 8 -------
9 9
10 1- GEOMETRY DEFINITION 10 1- GEOMETRY DEFINITION
11 11
12 AMS Ecal calorimeter is described in the join 12 AMS Ecal calorimeter is described in the joined documument : ams_ecal.pdf
13 13
14 - A single layer is a plane of scintillating 14 - A single layer is a plane of scintillating fibers within a box of
15 absorber material. 15 absorber material.
16 - Single layers are positionned (eg. placemen 16 - Single layers are positionned (eg. placement) within Module
17 (called SuperLayer in the descriptive docum 17 (called SuperLayer in the descriptive document),
18 alternatively with a relative offset of +- 18 alternatively with a relative offset of +- 0.25*distanceInterFibers.
19 - Modules are positionned within calorimeter, 19 - Modules are positionned within calorimeter, alternatively rotated of
20 90 deg around beam axis (X_axis). 20 90 deg around beam axis (X_axis).
21 Therefore all fibers are along Y_axis or Z_ 21 Therefore all fibers are along Y_axis or Z_axis calorimeter.
22 22
23 The default geometry is constructed in Detect 23 The default geometry is constructed in DetectorConstruction class.
24 In addition a transverse uniform magnetic fie 24 In addition a transverse uniform magnetic field can be applied.
25 25
26 2- PHYSICS LISTS 26 2- PHYSICS LISTS
27 27
28 Physics lists can be local (eg. in this exam 28 Physics lists can be local (eg. in this example) or from G4 kernel
29 (physics_lists subdirectory). 29 (physics_lists subdirectory).
30 30
31 - "local" standard EM physics with current ' 31 - "local" standard EM physics with current 'default' options.
32 32
33 From geant4/source/physics_lists/constructor 33 From geant4/source/physics_lists/constructors:
34 - "emstandard_opt0" standard EM physics wi 34 - "emstandard_opt0" standard EM physics with all default options
35 - "emstandard_opt1" best CPU performance s 35 - "emstandard_opt1" best CPU performance standard physics for LHC
36 - "emstandard_opt2" 36 - "emstandard_opt2"
37 - "emstandard_opt3" 37 - "emstandard_opt3"
38 38
39 Physics lists and options can be (re)set wit 39 Physics lists and options can be (re)set with UI commands
40 40
41 Please, notice that options set through G4Em 41 Please, notice that options set through G4EmProcessOPtions are global, eg
42 for all particle types. In G4 constructors, 42 for all particle types. In G4 constructors, it is shown how to set options per
43 particle type. 43 particle type.
44 44
45 3- PRIMARY GENERATOR : mono-energetic pencil 45 3- PRIMARY GENERATOR : mono-energetic pencil beam
46 46
47 The primary kinematic is a single particle w 47 The primary kinematic is a single particle which hits the calorimeter
48 perpendicular to the input face (eg. along X 48 perpendicular to the input face (eg. along X_axis).
49 The type of particle and its energy are set 49 The type of particle and its energy are set in the PrimaryGeneratorAction,
50 and can be changed via the G4 build-in comma 50 and can be changed via the G4 build-in commands of ParticleGun class
51 (see the macros provided with this example). 51 (see the macros provided with this example).
52 52
53 One can choose randomly the tranverse positi 53 One can choose randomly the tranverse position of the incident particle,
54 eg. the width of the beam. The associated in 54 eg. the width of the beam. The associated interactive command is built
55 in PrimaryGeneratorMessenger. 55 in PrimaryGeneratorMessenger.
56 56
57 4- DETECTOR RESPONSE 57 4- DETECTOR RESPONSE
58 58
59 The program computes the 'visible' energy, e 59 The program computes the 'visible' energy, eg. the energy deposited
60 in scintillating fibers. 60 in scintillating fibers.
61 61
62 It also computes the total energy deposited 62 It also computes the total energy deposited per layer, either in absorber
63 material or in scintillator material. 63 material or in scintillator material.
64 64
65 The list of fibers fired can be written even 65 The list of fibers fired can be written event per event, on an ascii file.
66 The file is filled at EndOfEvent(); uncommen 66 The file is filled at EndOfEvent(); uncomment the function WriteFibers()
67 See EventAction::WriteFibers() and the forma 67 See EventAction::WriteFibers() and the format description : eventFormat.txt
68 68
69 NB: visible energy can be corrected for Birk 69 NB: visible energy can be corrected for Birk's attenuation:
70 see the function SteppingAction::BirksAt 70 see the function SteppingAction::BirksAttenuation() (not activated)
71 71
72 5- HISTOGRAMS 72 5- HISTOGRAMS
73 73
74 The Program contains 5 built-in 1D histogram 74 The Program contains 5 built-in 1D histograms, managed by G4AnalysisManager.
75 These histograms can be activated individual 75 These histograms can be activated individually with the command :
76 /analysis/h1/set id nbBins valMin valMax un 76 /analysis/h1/set id nbBins valMin valMax unit
77 where unit is the desired unit for the histo 77 where unit is the desired unit for the histo (MeV, keV, etc..)
78 (see the macros xxxx.mac). 78 (see the macros xxxx.mac).
79 79
80 1 total energy in calorimeter (eg. summed a 80 1 total energy in calorimeter (eg. summed all layers)
81 2 vsible energy in calorimeter (eg. summed a 81 2 vsible energy in calorimeter (eg. summed all layers)
82 3 total energy per layer (eg. longitudinal p 82 3 total energy per layer (eg. longitudinal profile)
83 4 visible energy per layer (eg. longitudinal 83 4 visible energy per layer (eg. longitudinal profile)
84 5 visible energy per fiber (eg. lateral prof 84 5 visible energy per fiber (eg. lateral profile)
85 85
86 Histograms can be viewed using ROOT. 86 Histograms can be viewed using ROOT.
87 87
88 One can control the name and format of the h 88 One can control the name and format of the histograms file with the command:
89 /analysis/setFileName name (default amsEca 89 /analysis/setFileName name (default amsEcal)
90 /analysis/setFileType type (choice: root(d 90 /analysis/setFileType type (choice: root(default), XML, csv)
91 91
92 It is also possible to print selected histog 92 It is also possible to print selected histograms on an ascii file:
93 /analysis/h1/setAscii id 93 /analysis/h1/setAscii id
94 All selected histos will be written on a fil 94 All selected histos will be written on a file name.ascii (default amsEcal)
95 95
96 6- VISUALIZATION 96 6- VISUALIZATION
97 97
98 Visualization Manager is set in the main(). 98 Visualization Manager is set in the main().
99 Initialisation of the drawing is done via th 99 Initialisation of the drawing is done via the commands :
100 /vis/... in the macro vis.mac. In interactiv 100 /vis/... in the macro vis.mac. In interactive session:
101 PreInit or Idle > /control/execute vis.mac 101 PreInit or Idle > /control/execute vis.mac
102 102
103 Default view is a longitudinal view of the c 103 Default view is a longitudinal view of the calorimeter.
104 104
105 Tracks are drawn at end of event, and erased 105 Tracks are drawn at end of event, and erased at end of run.
106 Optionaly one can choose to draw all particl 106 Optionaly one can choose to draw all particles, only charged one, or none.
107 This command is defined in EventActionMessen 107 This command is defined in EventActionMessenger.
108 108
109 7- HOW TO START ? 109 7- HOW TO START ?
110 110
111 - compile and link to generate an executable 111 - compile and link to generate an executable
112 % cd amsEcal 112 % cd amsEcal
113 % gmake 113 % gmake
114 114
115 - execute amsEcal in 'batch' mode from macro 115 - execute amsEcal in 'batch' mode from macro files
116 % amsEcal run1.mac 116 % amsEcal run1.mac
117 117
118 - execute amsEcal in 'interactive mode' with 118 - execute amsEcal in 'interactive mode' with visualization
119 % amsEcal 119 % amsEcal
120 .... 120 ....
121 Idle> type your commands. For instance: 121 Idle> type your commands. For instance:
122 Idle> /control/execute run1.mac 122 Idle> /control/execute run1.mac
123 .... 123 ....
124 Idle> exit 124 Idle> exit
125 125
126 8- HANDLE RANDOM NUMBER SEEDS 126 8- HANDLE RANDOM NUMBER SEEDS
127 127
128 The macro rndmSeed.mac shows how to create a 128 The macro rndmSeed.mac shows how to create a set of random number seeds.
129 Here we save the seed at begin of each run ( 129 Here we save the seed at begin of each run (the number of events per run
130 is arbitrary). The seeds are stored in subdi 130 is arbitrary). The seeds are stored in subdirectory random.
131 131
132 Macro rndmSeed.mac shows also how to start a 132 Macro rndmSeed.mac shows also how to start a run from one of these seeds.