Gabriele Cosmo
69 lines
2.3 KiB
Plaintext
69 lines
2.3 KiB
Plaintext
$Id: README,v 1.1 2008/11/03 11:48:35 gcosmo Exp $
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------------------------------------------------------------
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Example of the external decayer implementation with Pythia6
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===========================================================
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The complete Pythia6 documentation can be found at:
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http://home.thep.lu.se/~torbjorn/pythiaaux/recent.html
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The Pythia6 external decayer was originally developed within
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the AliRoot framework, by Andreas Morsch (CERN).
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The dependence on the ALICE software was taken off
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by Christian Holm Christensen,
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The dependence on the Root framework and the integration in
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the Geant4 framework was done by Ivana Hrivnacova (IPN Orsay).
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The use of the external decayer is demonstrated on the modified
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novice N03 example.
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The G4Pythia6Decayer class provides the implementation of the
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G4VExternalDecayer interface with using Pythia6. In order
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to be able to use Pythia6, which is written in FORTRAN,
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a C++ interface class Pythia6 is provided. This class
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interfaces only the Pythia6 functions relevant to decay.
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The G4Pythia6Decayer is instantiated in the ExN03PhysicsList class,
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in the ConstructDecay() function.
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To demonstrate the decay with external decayer,
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the B- meson is defined in ExN03PrimaryGeneratorAction,
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as it has no own decay table defined within Geant4.
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With Pythia6, it is possible to force a selected decay
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type. This selection can be chosen interactively via
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the implemented Geant4 UI command:
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/pythia6Decayer/forceDecayType decayType
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where the available decay types are listed in the EDecayType
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enumaration.
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The classes Pythia6, G4Pythia6Decayer, G4Pythia6DecayerMessenger
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are independent from the example classes and can be reused
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in another user application.
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Installation:
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1. Download the Pythia6 source file from the Pythia6 download site:
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http://www.hepforge.org/downloads/pythia6
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2. Define the environment variables:
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PYTHIA6 the path to pythia-vesrinX.f source code
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PYTHIA6_VERSION the pythia version
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e.g. If you download pythia-6.4.18.f.gz and unzip it in $HOME,
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then you have to set:
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export PYTHIA6=$HOME
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export PYTHIA6_VERSION="6.4.18"
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3. cd $G4INSTALL/example/extended/eventgenerator/pythia/decayer6
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make
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Execution:
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% pythia6_decayer pythia6_decayer.in
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