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| 2 | ========================================================= |
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| 3 | Geant4 - ULTRA-based air shower example |
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| 4 | ========================================================= |
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| 5 | |
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| 6 | README |
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| 7 | --------------------- |
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| 8 | |
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| 9 | ------------------------------------------------------------------------| |
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| 10 | ----> Introduction. |
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| 11 | | |
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| 12 | The ULTRA detector is a hybrid 2-component system consisting of: |
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| 13 | | |
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| 14 | |
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| 15 | 1) an UV detection system - the UVscope | |
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| 16 | 2) an array of scintillator detectors - the ETscope |
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| 17 | | |
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| 18 | The UVscope detects Cherenkov light associated to cosmic ray showers |
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| 19 | when it is diffusively reflected on ground. | |
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| 20 | The ETscope detects in coincidence the charged particles of the shower. |
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| 21 | | |
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| 22 | In the current version only the UVscope simulation is included |
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| 23 | ------------------------------------------------------------------------| |
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| 24 | ----> Description |
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| 25 | | |
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| 26 | The UVscope consists of a Fresnel lens and a PMT located in the focal |
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| 27 | plane, enclosed in a cylindrical aluminum housing. The lens is 457 mm | |
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| 28 | in diameter and is made of UV transmitting acrylic with 5.6 grooves |
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| 29 | per mm. The description of the geometry of the Fresnel lens makes use | |
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| 30 | of object parameterisation/replication capabilities. |
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| 31 | | |
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| 32 | The primary vertex generator describes a plane circular source of UV |
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| 33 | (3eV, about 400 nm) optical photons. | |
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| 34 | Depending on the user selection (see below for the relevant environment |
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| 35 | variables) the source can be positioned such that the photons are fired | |
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| 36 | to a reflecting surface or, by default, directly to the UVscope |
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| 37 | (no reflecting surface is present in this case). | |
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| 38 | Reflection at the surface can be chosen to be specular or diffuse. |
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| 39 | In both cases the normal to the surface makes an angle of 45 degrees | |
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| 40 | with the UVscope axis and the photons are emitted at an angle of |
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| 41 | 90 degrees with the UVscope axis. | |
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| 42 | If none of these variables is set no reflecting surface is used |
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| 43 | and the photons source is positioned at the UVscope axis. |
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| 44 | | |
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| 45 | The definition of the relevant optical boundaries, parameters and |
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| 46 | processes is made. | |
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| 47 | |
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| 48 | ------------------------------------------------------------------------| |
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| 49 | ----> SET-UP |
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| 50 | | |
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| 51 | A standard Geant4 example GNUmakefile is provided | |
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| 52 | |
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| 53 | The following environment variables can be set: | |
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| 54 | |
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| 55 | setenv G4ANALYSIS_USE 1 |
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| 56 | |
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| 57 | setenv ULTRA_VERBOSE |
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| 58 | |
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| 59 | setenv ULTRA_MIRROR_USE 1 : A specular reflecting surface is used. |
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| 60 | setenv ULTRA_GROUND_USE 1 : A diffusive reflecting surface is used. |
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| 61 | |
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| 62 | ------------------------------------------------------------------------ |
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| 63 | |
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| 64 | Setup for analysis with iAIDA : for details, see Appendix 2 of the Users Guide for Application Developers |
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| 65 | |
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| 66 | Definition of environment variables (assuming AIDA_INSTALL is the directory where you installed iAIDA): |
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| 67 | |
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| 68 | setenv PATH ${PATH}:"$AIDA_INSTALL/bin" |
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| 69 | |
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| 70 | The following keywords can be used in UltraAnalysisManager.cc, |
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| 71 | in order to produce HBOOK, AIDA or ROOT histograms. |
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| 72 | |
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| 73 | "hbook" for HBOOK histograms |
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| 74 | "xml" for AIDA histograms |
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| 75 | "root" for ROOT histograms |
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| 76 | |
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| 77 | For more information on the AIDA interface: |
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| 78 | http://aida.freehep.org |
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| 79 | |
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| 80 | |
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| 81 | - |
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| 82 | |
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| 83 | ----------------------------------------------------------------------- |
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| 84 | ----> How to run the example. | |
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| 85 | |
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| 86 | - batch mode: |
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| 87 | $G4WORDIR/bin/Linux-g++/Ultra UltraMacro.mac | |
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| 88 | | |
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| 89 | - Interative mode: |
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| 90 | 3) $G4WORDIR/bin/Linux-g++/Ultra | |
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| 91 | |
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| 92 | ------------------------------------------------------------------------ |
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| 93 | ----> Simulation output | |
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| 94 | |
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| 95 | if G4ANALYSIS_USE = 1 in the set-up, the output is ultra.aida | |
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| 96 | It contains: |
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| 97 | 1)1Dhistogram with the detected photons energy (eV) | |
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| 98 | 2)1Dhistogram with the number of detected photons per event | |
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| 99 | |
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| 100 | ------------------------------------------------------------------------ |
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| 101 | ----> Visualisation | |
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| 102 | |
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| 103 | a macro is provided as example of visulisation: Visualisation.mac | |
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| 104 | to run it : $G4WORKDIR/bin/Linux-g++/Ultra Visualisation.mac |
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| 105 | ------------------------------------------------------------------------ |
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| 106 | |
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| 107 | for comments and questions: bernardo@lip.pt |
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| 108 | for more info http://www.ge.infn.it/geant4/examples/ |
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| 109 | |
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| 110 | last modified: B. Tome 16/11/2009 |
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| 111 | created by : B. Tome and M.C. Espirito Santo 20/05/2004 |
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