Gabriele Cosmo
89 lines
3.0 KiB
Plaintext
89 lines
3.0 KiB
Plaintext
$Id: README,v 1.5 2004/09/01 09:56:08 japost Exp $
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-------------------------------------------------------------------
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=========================================================
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Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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=========================================================
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field02
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-------
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Test for investigation of tracking in electric field
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and field dependent electromagnetic processes.
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1- FIELD DEFINITION
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The field is a constant electric field.
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Technical note: in order to use any electric field, it is
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necessary to create the objects for its equation of motion,
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the stepper and driver for the integration, and the
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chord finder.
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The class that does these is F02ElectricFieldSetup.
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1- GEOMETRY DEFINITION
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The "absorber" is a solid made of a given material.
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Three parameters define the absorber :
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- the material of the absorber,
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- the thickness of an absorber,
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- the transverse size of the absorber (the input face is a square).
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The volume "World" contains the "absorber".
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In this test the parameters of the "World" can be changed , too.
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In addition a transverse uniform magnetic field can be applied.
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The default geometry is constructed in DetectorConstruction class,
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but all the parameters can be changed via
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the commands defined in the DetectorMessenger class.
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2- AN EVENT : THE PRIMARY GENERATOR
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The primary kinematic consists of a single particle which hits the
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absorber perpendicular to the input face. The type of the particle
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and its energy are set in the PrimaryGeneratorAction class, and can
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be changed via the G4 build-in commands of ParticleGun class (see
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the macros provided with this example).
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A RUN is a set of events.
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3- DETECTOR RESPONSE
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A HIT is a record, event per event , of all the
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informations needed to simulate and analyse the detector response.
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In this example a CalorHit is defined as a set of 2 informations:
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- the total energy deposit in the absorber,
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- the total tracklength of all charged particles in the absorber,
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Therefore the absorber is declared
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'sensitive detector' (SD), which means they can contribute to the hit.
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4- PHYSICS DEMO
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The particle's type and the physic processes which will be available
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in this example are set in PhysicsList class.
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The messenger classes introduce interactive commands . Using these
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commands the geometry of the detector, the data of the primary
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particle, etc. can be changed.
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5- HOW TO START ?
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- compile and link to generate an executable
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% cd $G4INSTALL/example/extended/field/field02
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% gmake
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- execute field02 in 'batch' mode from macro file e.g.
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% $(G4INSTALL)/bin/$(G4SYSTEM)/field02 field02.in
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- execute field02 in 'interactive' mode with visualization e.g.
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% $(G4INSTALL)/bin/$(G4SYSTEM)/field02
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....
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Idle> type your commands
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....
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