[807] | 1 | $Id: README,v 1.5 2006/05/18 08:16:42 grichine Exp $ |
---|
| 2 | ------------------------------------------------------------------- |
---|
| 3 | |
---|
| 4 | ========================================================= |
---|
| 5 | Geant4 - an Object-Oriented Toolkit for Simulation in HEP |
---|
| 6 | ========================================================= |
---|
| 7 | |
---|
| 8 | TestEm10 |
---|
| 9 | -------- |
---|
| 10 | |
---|
| 11 | Test for investigation of ionisation in thin absorbers, transition |
---|
| 12 | and synchrotron radiations. Default setup for "TestEm10.in" and "TestEm10.large_N.in" is |
---|
| 13 | the experiment for XTR with NIM A294 (1990) 465-472 (fig. 11) setup |
---|
| 14 | |
---|
| 15 | |
---|
| 16 | 0- INTRODUCTION |
---|
| 17 | |
---|
| 18 | The parameterisations models can be changed simply with: |
---|
| 19 | |
---|
| 20 | Idle> /XTRdetector/setModel i (i = 1 to 10) |
---|
| 21 | |
---|
| 22 | It is NOT needed (and not recommended) to issue the command |
---|
| 23 | /XTRdetector/update if just the model is changed. |
---|
| 24 | |
---|
| 25 | See macro file "TestEm10.in" for an example. |
---|
| 26 | |
---|
| 27 | |
---|
| 28 | 1- GEOMETRY DEFINITION |
---|
| 29 | |
---|
| 30 | The "absorber" is a tube made of a given material. |
---|
| 31 | |
---|
| 32 | Three parameters define the absorber : |
---|
| 33 | - the material of the absorber, |
---|
| 34 | - the thickness of an absorber, |
---|
| 35 | - the transverse size of the absorber (the input face is a square). |
---|
| 36 | |
---|
| 37 | The volume "World" contains the "absorber". |
---|
| 38 | In this test the parameters of the "World" can be changed , too. |
---|
| 39 | |
---|
| 40 | In addition a transverse uniform magnetic field can be applied. |
---|
| 41 | |
---|
| 42 | The default geometry is constructed in DetectorConstruction class, |
---|
| 43 | but all the parameters can be changed via |
---|
| 44 | the commands defined in the DetectorMessenger class. |
---|
| 45 | |
---|
| 46 | 2- AN EVENT : THE PRIMARY GENERATOR |
---|
| 47 | |
---|
| 48 | The primary kinematic consists of a single particle which hits the |
---|
| 49 | absorber perpendicular to the input face. The type of the particle |
---|
| 50 | and its energy are set in the PrimaryGeneratorAction class, and can |
---|
| 51 | be changed via the G4 build-in commands of ParticleGun class (see |
---|
| 52 | the macros provided with this example). |
---|
| 53 | |
---|
| 54 | A RUN is a set of events. |
---|
| 55 | |
---|
| 56 | 3- DETECTOR RESPONSE |
---|
| 57 | |
---|
| 58 | Here we test G4PAIionisation , G4IonisationByLogicalVolume and |
---|
| 59 | transition radiation processes |
---|
| 60 | |
---|
| 61 | A HIT is a record, event per event , of all the |
---|
| 62 | informations needed to simulate and analyse the detector response. |
---|
| 63 | |
---|
| 64 | In this example a CalorHit is defined as a set of 2 informations: |
---|
| 65 | - the total energy deposit in the absorber, |
---|
| 66 | - the total tracklength of all charged particles in the absorber, |
---|
| 67 | |
---|
| 68 | Therefore the absorber is declared |
---|
| 69 | 'sensitive detector' (SD), which means they can contribute to the hit. |
---|
| 70 | |
---|
| 71 | At the end of a run, from the histogram(s), one can study |
---|
| 72 | different physics quantities such as : |
---|
| 73 | - angle distribution, |
---|
| 74 | - energy deposit, |
---|
| 75 | - transmission/backscattering, |
---|
| 76 | - ... |
---|
| 77 | |
---|
| 78 | The test contains 10 built-in histograms, which can be activated by |
---|
| 79 | interactive commands (see the macros runxx.mac for details). |
---|
| 80 | |
---|
| 81 | The histogram files can be viewed using PAW e.g with the commands |
---|
| 82 | |
---|
| 83 | paw> h/file 1 geant4.plot01 or g4.p11 |
---|
| 84 | paw> option stat |
---|
| 85 | paw> h/pl 1 |
---|
| 86 | |
---|
| 87 | |
---|
| 88 | |
---|
| 89 | 4- PHYSICS DEMO |
---|
| 90 | |
---|
| 91 | The particle's type and the physic processes which will be available |
---|
| 92 | in this example are set in PhysicsList class. |
---|
| 93 | |
---|
| 94 | The messenger classes introduce interactive commands . Using these |
---|
| 95 | commands the geometry of the detector, the data of the primary |
---|
| 96 | particle, the limits of the histograms , etc. can be changed. |
---|
| 97 | |
---|
| 98 | |
---|
| 99 | 5- HOW TO START ? |
---|
| 100 | |
---|
| 101 | - compile and link to generate an executable |
---|
| 102 | % cd TestEm10 |
---|
| 103 | % gmake |
---|
| 104 | |
---|
| 105 | - execute TestEm10 in 'batch' mode from macro files e.g. |
---|
| 106 | % $(G4INSTALL)/bin/$(G4SYSTEM)/TestEm10 run11.mac |
---|
| 107 | |
---|
| 108 | - execute TestEm10 in 'interactive' mode with visualization e.g. |
---|
| 109 | % $(G4INSTALL)/bin/$(G4SYSTEM)/TestEm10 |
---|
| 110 | .... |
---|
| 111 | Idle> type your commands |
---|
| 112 | .... |
---|
| 113 | |
---|
| 114 | List of the built-in histograms |
---|
| 115 | ------------------------------- |
---|
| 116 | |
---|
| 117 | 1. number of (tracking) steps/event |
---|
| 118 | 2. energy deposit distribution in the absorber (in MeV) |
---|
| 119 | 3. angle distribution of the primary particle at the exit |
---|
| 120 | of the absorber (deg) |
---|
| 121 | 4. distribution of the lateral displacement at exit(mm) |
---|
| 122 | 5. kinetic energy of the transmitted primaries (MeV) |
---|
| 123 | 6. angle distribution of the backscattered primaries (deg) |
---|
| 124 | 7. kinetic energy of the backscattered primary particles (MeV) |
---|
| 125 | 8. kinetic energy of the charged secondary particles (MeV) |
---|
| 126 | 9. z distribution of the secondary charged vertices (mm) |
---|
| 127 | 10. kinetic energy of the photons escaping the absorber (MeV) |
---|
| 128 | |
---|
| 129 | |
---|
| 130 | Using histograms |
---|
| 131 | ---------------- |
---|
| 132 | |
---|
| 133 | By default the histograms are not activated. To activate histograms |
---|
| 134 | the environment variable G4ANALYSIS_USE should be defined. For instance |
---|
| 135 | uncomment the flag G4ANALYSIS_USE in GNUmakefile. |
---|
| 136 | |
---|
| 137 | To use histograms any of implementations of AIDA interfaces should |
---|
| 138 | be available (see http://aida.freehep.org). |
---|
| 139 | |
---|
| 140 | A package including AIDA and extended interfaces also using Python |
---|
| 141 | is PI, available from: http://cern.ch/pi . |
---|
| 142 | |
---|
| 143 | Once installed PI or PI-Lite in a specified local area $MYPY, it is |
---|
| 144 | required to add the installation path to $PATH, i.e. for example, |
---|
| 145 | for release 1.2.1 of PI: |
---|
| 146 | |
---|
| 147 | setenv PATH ${PATH}:$MYPI/1.2.1/app/releases/PI/PI_1_2_1/rh73_gcc32/bin |
---|
| 148 | |
---|
| 149 | CERN users can use the PATH to the LCG area on AFS. |
---|
| 150 | |
---|
| 151 | Before compilation of the example it is optimal to clean up old |
---|
| 152 | files: |
---|
| 153 | |
---|
| 154 | gmake histclean |
---|
| 155 | gmake |
---|
| 156 | |
---|
| 157 | Before running the example the command should be issued: |
---|
| 158 | |
---|
| 159 | eval `aida-config --runtime csh` |
---|
| 160 | |
---|
| 161 | It is possible to choose the format of the output file with |
---|
| 162 | histograms using UI command: |
---|
| 163 | |
---|
| 164 | /testem/histo/setFileType type |
---|
| 165 | |
---|
| 166 | The following types are available: hbook, root, xml. |
---|