Getting started with Geant4

Geant4 is an open-source toolkit that enables to simulate particle passage through matter. It is written in C++ and offers a wide range of tools for users to employ in their applications. More information on the overview of the package can be found in the Introduction to Geant4.

Where to find information?

Geant4 is documented in several user guides for different steps of development with Geant4.

Numerous example applications are distributed with each Geant4 release (under examples/), offering a preview and a demonstration of Geant4 capabilities. Beginner users are invited to consult them and use as a base for their applications. More information on the examples can be found in the Application Developers Guide.

Geant4 tutorials are often held in various parts of the world. Consult events calendar to search for incoming events, but also to have a look at past editions, which contain the educational material.

Do we want to link to most recent tutorials, e.g. G4 beginners tutorial?

How to install?

Geant4 can be used on Linux, macOS, and Windows (see supported and tested platforms).

Visit download page to get the latest Geant4 release.

Details on the requirements, installation steps, and post-installation setup are described in the Installation Guide.

Information on how to install your application, or Geant4 examples, can be found in the same guide.

How to write an application?

Geant4 is a toolkit, therefore it provides necessary tools for users to write their simulation applications. Consult Application Developers Guide to learn how Geant4 application should bee structured, what elements are needed, and how to customise the application to your needs.

Set of example applications is distributed with Geant4 (examples/), to demonstrate the implementation of customised simulations.

More detailed information on advanced topics can be found in other user guides:

  • Physics Reference Manual describes physics interactions simulated in Geant4.
  • Physics List Guide is a brief guide over the pre-defined sets of physics interactions (called reference physics lists), and in particular differences in the electromagnetic options.
  • Toolkit Developers Guide covers more advanced topics, explaining the design of the toolkit, and information on how to extend it, e.g. by implementing a new physics process.

Frequently Asked Questions

Frequently asked questions are summarised in this guide.

Where to look for help?

If you cannot find answer to your questions in the user guides or the examples and their documentation, try browsing the user forum to see if someone has already encountered a similar problem, otherwise, post it.

If you want to report a bug, please use Geant4 Problem Tracking System.