Gabriele Cosmo
110 lines
3.8 KiB
Plaintext
110 lines
3.8 KiB
Plaintext
$Id: README,v 1.2 2000/01/21 10:56:13 maire 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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TestEm2
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-------
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This example allows to do the shower development of an single primary
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particle, and to survey the physics processes which occur,
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with printing and visualization.
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1- GEOMETRY DEFINITION
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The geometry consists of a cylinder of homegenous material.
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This cylinder is replicated longitudinaly (slice) and radialy (ring).
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The default geometry is constructed in DetectorConstruction class,
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but all of the above parameters can be modified interactively via
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the commands defined in the DetectorMessenger class.
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Material can be choosen: Air Water lAr Al Fe BGO PbWO4 Pb.
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eg: /calor/setMat PbWO4
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The size of the slices and rings are expressed in radiation length units
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and can be changed.
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eg: /calor/setLbin 20 1. ---> 20 slices of 1. radl
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/calor/setRbin 5 0.25 ---> 5 rings of 0.25 radl
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/calor/update ---> rebuild the geometry
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An uniform magnetic field along the cylinder axis can be set.
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eg: /calor/setField 5 tesla
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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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cylinder 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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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- VISUALIZATION
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The Visualization Manager is set in the main().
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The initialisation of the drawing is done via the command
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/vis~/create_view in the macro init.mac. This macro is
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automatically read from the main in case of interactive running mode.
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The detector has a default view which is a longitudinal view of the
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cylinder.
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The tracks are drawn at the end of event, and erased at the end of run.
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Optionaly one can choose to draw all particles, only the charged one,
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or none. This command is defined in EventActionMessenger class.
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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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In addition a build-in interactive command (/process/inactivate proname)
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allows to activate/inactivate the processes one by one.
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The threshold for producing secondaries can be changed.
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eg: /run/particle/setCut 100 microm
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/run/initialize
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5- HOW TO START ?
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- compile and link to generate an executable
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% cd TestEm2
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% gmake
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- execute TestEm2 in 'batch' mode from macro files
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% TestEm2 run01.mac
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- execute TestEm2 in 'interactive mode' with visualization
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% TestEm2
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....
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Idle> type your commands. For instance:
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Idle> /control/execute newgeom.mac
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....
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Idle> exit
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7- HISTOGRAMS
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TestEm2 produces several histo which are saved as testem2.histo
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Content of these histo:
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1 : energy deposit per event
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2 : charged track length per event
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3 : neutral track length per event
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4 : longitudinal energy profile
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5 : cumulated longitudinal energy profile
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6 : rms of cumulated longitudinal energy profile
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7 : gamma's flux
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8 : positron's flux
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9 : electron's flux
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10 : radial energy profile
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11 : cumulated radial energy profile
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12 : rms of cumulated radial energy profile
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