Particle Detector Simulation (I) Using Geant4

Ahmed Sayed Hamed (master student) Introduction

GEANT4 (GEometry ANd Tracking version 4) is an Object- Oriented Programming (OOP) Toolkit for the simulation of the passage of particles through matter. Geant4 nowadays used by a wide scientific community worldwide in diverse experimental domains.

It is also used in production by large scale high energy and nuclear physics experiments as well as in smaller scale detector development projects.

Geant4 provides many packages specialized for modeling both electromagnetic and hadronic physic interactions at different energies. Objective

At the end of this presentation we will learn the

basics of geometry description with simple

placements (location, rotation).

Part I How to define detector geometry

For example: Creating Cylinder Logical volume Physical volume How to specify detector material

There are various methods to specify materials

For example, Defining air and water from the internal Geant4 database. How to set up

• Prepare directory for your application.

In that directory

• myApplication.cc – A file in which main() is defined

• includes/ – Directory for header files (class definition) for mandatory user classes and optional user run action classes.

• src/ – Directory for source files (class implementation) for the above classes.

• GNUmakefile – A make file describing how to build the application

Application directory Part (II) Practice

Step-0 Setup Copy the application and unpack it in the work directory (~/work/). Step-1 Compile and run $ make clean $ make –j 2 ... Done! $ export G4VRMLFILE_MAX_FILE_NUM=0 $ $G4WORKDIR/bin/Linux-g++/expd2 Idle> /control/execute vis.mac Idle> exit $ ls $ vrmlview g4_00.wrl

• $ $G4WORKDIR/bin/Linux-g++/expd2 • ... • Idle> /control/execute vis.mac • ... • Idle> /control/execute gun.mac • ... • Idle> /run/beamOn 5

References

1- Geant4 Application Developers Guide 2- http://wiki.kek.jp

Thank you