GEANT is the name of a series of simulation software designed to describe the passage of
elementary particles
In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. Particles currently thought to be elementary include electrons, the fundamental fermions (quarks, leptons, an ...
through matter, using
Monte Carlo method
Monte Carlo methods, or Monte Carlo experiments, are a broad class of computational algorithms that rely on repeated random sampling to obtain numerical results. The underlying concept is to use randomness to solve problems that might be deter ...
s. The name is an
acronym
An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in '' NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, a ...
formed from "GEometry ANd Tracking". Originally developed at
CERN for
high energy physics
Particle physics or high energy physics is the study of fundamental particles and forces that constitute matter and radiation. The fundamental particles in the universe are classified in the Standard Model as fermions (matter particles) and b ...
experiments, GEANT-3 has been used in many other fields.
History
The very first version of GEANT dates back to 1974, while the first version of GEANT-3 dates back to 1982. Versions of GEANT through 3.21 were written in
FORTRAN and eventually maintained as part of
CERNLIB. Since about 2000, the last FORTRAN release has been essentially in stasis and receives only occasional bug fixes. GEANT3 was, however, still in use by some experiments for some time thereafter. Most of GEANT-3 is available under the
GNU General Public License
The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end user
In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ulti ...
, with the exception
of some hadronic interaction code contributed by the
FLUKA
FLUKA (FLUktuierende KAskade) is a fully integrated Monte Carlo simulation package for the interaction and transport of particles and nuclei in matter.
FLUKA has many applications in particle physics, high energy experimental physics and engine ...
collaboration.
GEANT-3 was used by a majority of high energy physics experiments from the late 1980s to the early 2000s. The largest experiments using were three of the experiments at the
Large Electron-Positron collider
Large means of great size.
Large may also refer to:
Mathematics
* Arbitrarily large, a phrase in mathematics
* Large cardinal, a property of certain transfinite numbers
* Large category, a category with a proper class of objects and morphisms (o ...
, including
ALEPH
Aleph (or alef or alif, transliterated ʾ) is the first letter of the Semitic abjads, including Phoenician , Hebrew , Aramaic , Syriac , Arabic ʾ and North Arabian 𐪑. It also appears as South Arabian 𐩱 and Ge'ez .
These let ...
,
L3 and
OPAL
Opal is a hydrated amorphous form of silica (SiO2·''n''H2O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Due to its amorphous property, it is classified as a mineraloid, unlike crystalline forms ...
. It was also a key tool in the design and optimization of the detectors of all experiments at the Large Hadron Collider (LHC) – see e.g. the ATLA
Technical Design Report GEANT-3.21 based programs remained main simulation engine of ATLAS, CMS and LHCb at LHC until 2004, when these experiments moved to Geant4-based simulations. Even in 2019 it remains the primary simulation tool for the ALICE experiment at the LHC.
A related (but separate) product is
Geant4
Geant4 (for GEometry ANd Tracking) is a platform for "the simulation of the passage of particles through matter" using Monte Carlo methods. It is the successor of the GEANT series of software toolkits developed bThe Geant4 Collaboration and th ...
(when referring to this version, the name is typically no longer capitalized). It is a
complete rewrite in
C++ with a modern
object-oriented
Object-oriented programming (OOP) is a programming paradigm based on the concept of " objects", which can contain data and code. The data is in the form of fields (often known as attributes or ''properties''), and the code is in the form of ...
design. Geant4 was developed by the RD44 collaboration in 1994–1998 and is being maintained and improved now by the Geant4 international collaboration. For quite some time Geant4 did not have a clearly defined software license. As of version 8.1 (released June 30, 2006) this omission has been remedied. Geant4 is now available under th
Geant4 Software License
See also
*
EGS (program) __NOTOC__
The EGS (Electron Gamma Shower) computer code system is a general purpose package for the Monte Carlo simulation of the coupled transport of electrons and photons in an arbitrary geometry for particles with energies from a few keV up to se ...
*
CLHEP
CLHEP (short for ''A Class Library for High Energy Physics'') is a C++ library that provides utility classes for general numerical programming, vector arithmetic, geometry, pseudorandom number generation, and linear algebra, specifically targe ...
and
FreeHEP, libraries for high energy physics
References
{{Reflist
External links
Geant4publicly accessible webpage
GEANTwebpage at CERN (only available to CERN users)
Free software programmed in Fortran
Monte Carlo particle physics software
Physics software
CERN software