Introduction to GAMBIT

Evidence for new physics Beyond the Standard Model (BSM) could appear in any observable in particle, astroparticle or nuclear physics. This means that if a BSM model is to be proven or disproven it is necessary to analyse the data from many different experimental sources simultaneously. Global fits attempt to tackle this problem, combining theoretical observable predictions with targeted searches of experimental data.

GAMBIT, the Global And Modular BSM Inference Tool, is one of a number of global fitting software frameworks. However, GAMBIT is designed to offer a number of advantages over existing solutions including theory flexibility, straightforward extension to new observables and external interfaces, code availability, statistical secularism and computational speed.

Gambit consists of a number of modules or Bits, along with various Core components and utilities. GAMBIT’s Bits are:

ColliderBitCalculates particle collider observables and likelihoods. Includes detailed implementations of LEP, ATLAS and CMS searches for new particle production, and measurements of the Higgs boson.
FlavBitCalculates observables and likelihoods from flavor physics, in particular B, D, and K meson decays as observed by LHCb, including angular observables and correlations.
DarkBitCalculates Dark Matter observables and likelihoods, from the relic abundance to direct and indirect searches.
SpecBitInterfaces to one of a number of possible external spectrum generators in order to determine pole masses and running parameters, and provides them to the rest of GAMBIT in a standardised spectrum container format.
DecayBitCalculates decay rates of all relevant particles in the BSM theory under investigation, and contains decay data for all Standard Model particles.
ScannerBitThe sampling module for Gambit. Implements various scanners which are programmed as plugins.
CosmoBitComputes cosmological observables and likelihoods. Can be used for studying models of inflation and variations in the properties of elementary particles, among other topics.
NeutrinoBitCalculates observables and likelihoods for neutrino physics.
PrecisionBitCalculation of precision observables and likelihoods.
ObjectivesBitProvides standard test functions.

How do I run GAMBIT?

To run a limited version of GAMBIT quickly and easily, use the Docker image. A pre-built version of GAMBIT is available as a Docker image which can be downloaded and run locally. For detailed instructions please see the Docker Usage page.

To access and use all features of GAMBIT, build from source. GAMBIT builds and runs under Linux and macOS. For detailed instructions please see the Installation for Linux or Installation for macOS pages. Although Windows is not directly supported, it is possible to install Linux on Windows using WSL. See Installation for Windows for more information.