| Geant4 Cross Reference |
1 ---------------------------------------------- 1 -------------------------------------------------------------------
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 TestEm4 7 TestEm4
8 ------- 8 -------
9 9
10 Plot energy deposited by 9 MeV photon beam in 10 Plot energy deposited by 9 MeV photon beam in an homogeneous medium.
11 11
12 1- GEOMETRY DEFINITION 12 1- GEOMETRY DEFINITION
13 13
14 It is a cylinder of 5 cm radius filled with 14 It is a cylinder of 5 cm radius filled with C6F6.
15 15
16 2- PHYSICS LIST 16 2- PHYSICS LIST
17 17
18 The particle list contains only gamma, elect 18 The particle list contains only gamma, electron,positron.
19 The physics list contains the 'standard' ele 19 The physics list contains the 'standard' electromagnetic processes.
20 20
21 3- AN EVENT : THE PRIMARY GENERATOR 21 3- AN EVENT : THE PRIMARY GENERATOR
22 22
23 The primary kinematic is a single 9 MeV gamm 23 The primary kinematic is a single 9 MeV gamma randomly shooted at the
24 middle of the cylinder. 24 middle of the cylinder.
25 25
26 4- VISUALIZATION 26 4- VISUALIZATION
27 27
28 The Visualization Manager is set in the main 28 The Visualization Manager is set in the main().
29 The initialisation of the drawing is done vi 29 The initialisation of the drawing is done via the commands
30 /vis/.. in the macro vis.mac. This macro is 30 /vis/.. in the macro vis.mac. This macro is
31 automatically read from the main in case of 31 automatically read from the main in case of interactive running mode.
32 32
33 The detector has a default view which is a t 33 The detector has a default view which is a transversal view of the
34 cylinder. 34 cylinder.
35 35
36 The tracks are drawn at the end of event, an 36 The tracks are drawn at the end of event, and erased at the end of run.
37 Optionaly one can choose to draw all particl 37 Optionaly one can choose to draw all particles, only the charged one,
38 or none. This command is defined in EventAct 38 or none. This command is defined in EventActionMessenger class.
39 39
40 5- PHYSICS SURVEY 40 5- PHYSICS SURVEY
41 41
42 The energy deposited in C6F6 is histogramed 42 The energy deposited in C6F6 is histogramed.
43 43
44 6- HOW TO START ? 44 6- HOW TO START ?
45 45
46 - execute TestEm4 in 'batch' mode from macro 46 - execute TestEm4 in 'batch' mode from macro files
47 % TestEm4 TestEm4.in 47 % TestEm4 TestEm4.in
48 48
49 - execute TestEm4 in 'interactive mode' with 49 - execute TestEm4 in 'interactive mode' with visualization
50 % TestEm4 50 % TestEm4
51 .... 51 ....
52 Idle> type your commands 52 Idle> type your commands
53 .... 53 ....
54 Idle> exit 54 Idle> exit
55 <<
56 macro verbose.mac illustrate capabili <<
57 55
58 7- USING HISTOGRAMS 56 7- USING HISTOGRAMS
59 57
60 The format of the histogram file can be : roo 58 The format of the histogram file can be : root (default),
61 xml, csv, by selecting g4nnn.hh in RunAction. 59 xml, csv, by selecting g4nnn.hh in RunAction.hh
62 60
63 8- RANDOM NUMBERS HANDLING 61 8- RANDOM NUMBERS HANDLING
64 62
65 CLHEP provides several random number engine 63 CLHEP provides several random number engines. In this example the Ranecu
66 engine is choosen at beginning of the main 64 engine is choosen at beginning of the main (TestEm4.cc).
67 65
68 By default, G4RunManager does not save the 66 By default, G4RunManager does not save the rndm seed.
69 To do so the user must set in BeginOfRunAct 67 To do so the user must set in BeginOfRunAction:
70 G4RunManager::GetRunManager()->SetRandomNum 68 G4RunManager::GetRunManager()->SetRandomNumberStore(true);
71 69
72 Then the rndm seed is systematically saved 70 Then the rndm seed is systematically saved at beginning of run
73 (currentRun.rndm) and beginning of event (c 71 (currentRun.rndm) and beginning of event (currentEvent.rndm)
74 Therefore, in case of abnormal end, the see 72 Therefore, in case of abnormal end, the seed of the last event processed
75 is available in currentEvent.rndm 73 is available in currentEvent.rndm
76 74
77 Even in case of normal run processing, the 75 Even in case of normal run processing, the user may wish to preserve the
78 rndm seed of selected events. At any time i 76 rndm seed of selected events. At any time in the event, put the
79 following statement: 77 following statement:
80 if (condition) G4RunManager::GetRunManager( 78 if (condition) G4RunManager::GetRunManager()->rndmSaveThisEvent();
81 currentEvent.rndm will be copied to runXXev 79 currentEvent.rndm will be copied to runXXevntYY.rndm
82 (see SteppingAction::UserSteppingAction() ) 80 (see SteppingAction::UserSteppingAction() )
83 81
84 To restart a run from a given rndm seed, us 82 To restart a run from a given rndm seed, use the UI command :
85 /random/resetEngineFrom fileName 83 /random/resetEngineFrom fileName
86 84
87 The macro rndmSeed.mac shows how to save an 85 The macro rndmSeed.mac shows how to save and reset the random number
88 seed between runs, from UI commands. 86 seed between runs, from UI commands.