User Documents and Examples II

Geant4 Tutorial atMarshall Space Flight Center

18 April 2012Dennis Wright (SLAC)

Geant4 V9.5

User Documents

• http://geant4.web.cern.ch/geant4/support/userdocuments.shtml

• Application Developers Guide

• Toolkit Developers' Guide– for those who want to contribute to the extension of the

functionality to the Geant4 toolkit

• Physics Reference Manual– a detailed description of the physics interactions provided

in the Geant4 toolkit

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Toolkit Developers' Guide

• http://geant4.web.cern.ch/geant4/UserDocumentation/UsersGuides/ForToolkitDeveloper/html/index.html

• For developers and experienced users of Geant4• already familiar with functionality of the Geant4 toolkit as

explained in the ``User‘s Guide For Application Developers“• a working knowledge of programming using C++ is assumed

• Includes• a description of the object-oriented design of the Geant4 toolkit• philosophy behind design choices• a guide for users who want to extend the functionality of

Geant4: adding new solids, modifying the navigator, creating new fields, etc.

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Physics Reference Manual• http://geant4.web.cern.ch/geant4/UserDocumentation/

UsersGuides/PhysicsReferenceManual/fo/PhysicsReferenceManual.pdf

• presents the theoretical formulation, model, or parameterization of the physics interactions included in Geant4

• Describes the probability of occurrence of an interaction and the sampling mechanisms required to simulate it

• Serves as a reference for toolkit users and developers who wish to consult the underlying physics of an interaction.

• The Physics Reference Manual contains gaps in documentation which correspond to un-implemented interactions. There are also a few sections in which documentation is slight

• No more html version, only pdf version is available.4

Examples

• Novice Examples

• Extended Examples purpose:– testing and validation of processes and tracking– demonstration of Geant4 tools – extending the functionality of Geant4.

• Advanced Examples purpose:– illustrate realistic applications of Geant4 in typical experimental

environments

• Extended and advanced examples currently undergoing redesign and update

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Extended Examples• Chapter 9 of Application Developers Guide• Examples for testing and validation of processes and tracking

• electromagnetic (TestEm0 – TestEm18) , Hadronic• radioactive decay, polarization• EM field (field01 – field04)• Geometry (volume overlap test)

• Examples to demonstrate Geant4 tools• Analysis, event generator, g3tog4, persistency• Biasing (B01-B02), optical, run and event• Parameterisations (GFLASH

• Examples which extend the functionality of Geant4.• parallel computing (ExDINE, MPI and TopC)

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Extended Examplesgeant4/examples/extended

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Advanced Examples

• Chapter 9 of Application Developers Guide

• Examples of realistic applications of Geant4 in typical experimental environments

• Examples of how to use analysis tools (histograms, ntuples, plotting and and so on)

• Visualization examples

• Examples of advanced user interface facilities

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Advanced Examples geant4/examples/advanced

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Gamma Ray Telescope

• Simulation of a gamma ray space telescope • very similar to Fermi

Gamma Space Telescope

• Studies the tracking and calorimetry of ~GeV gammas• 16 Si foil tracker towers• 16 CsI calorimeters• GammaRayTelPhysicsList• customized particle

generator• AIDA-based analysis

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•

X-ray Telescope

• Simulation of XMM Newton telescope• first application of Geant4

• Studies the focusing of background protons onto focal plane arrays• carbon fiber tube, x-ray

mirrors• XrayTelPhysicsList• G4hMultipleScattering is

main process• General Particle Source• AIDA-based analysis

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•

Underground Physics

• Realistic example of underground dark matter search experiment

• Full lab geometry• desks, cupboards, door and

windows• important for neutron

scattering• Physics

• low energy, standard EM• neutron HP• optical processes• radioactive decay

• General particle source

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PMT

Laboratory

Liquid/Gas Xe Scintillator including grids + calibrator

Concrete Cavern also implemented

Hadron Therapy

• Specifically developed to address needs of proton and ion therapy

• Proton beam line • Standard geometry for IAEA

benchmark

• Physics– Reference Physics Lists– Specific 'local' physics list

for the ion-ion interactions

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Water Phantom

Proton beam line for eye-treatments installed at the INFN-LNS facility in Catania

Human Phantom

• Anthropomorphic phantoms for Geant4 simulations

• Two models are available– MIRD and ORNL– male and female for each

model• Some geometries are

implemented through GDML

• Physics Processes– standard EM processes

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MIRD Female Phantom with particle tracks

Summary

• Toolkit Developers' Guide• for a deeper knowledge of the structure and philosophy of

Geant4• Physics Reference Manual

• to learn about the physics of Geant4• Extended Examples

• concrete applications which demonstrate Geant4 tools and capabilities

• Advanced Examples• concrete applications of Geant4 in typical experimental

environments

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