# FlavBit: A GAMBIT module for computing flavour observables and likelihoods

## TL;DR

FlavBit is a module within GAMBIT that calculates flavour physics observables and likelihoods, enabling detailed testing of new physics models against experimental data, including uncertainties and correlations.

## Contribution

It introduces FlavBit, a new dedicated flavour physics module with comprehensive likelihood routines and integration with external theory codes for the GAMBIT framework.

## Key findings

- Supports a wide range of flavour observables including B, D mesons, kaons, and pions.
- Allows detailed comparison of theoretical predictions with experimental data.
- Demonstrates use in supersymmetry and effective field theory analyses.

## Abstract

Flavour physics observables are excellent probes of new physics up to very high energy scales. Here we present FlavBit, the dedicated flavour physics module of the global-fitting package GAMBIT. FlavBit includes custom implementations of various likelihood routines for a wide range of flavour observables, including detailed uncertainties and correlations associated with LHCb measurements of rare, leptonic and semileptonic decays of B and D mesons, kaons and pions. It provides a generalised interface to external theory codes such as SuperIso, allowing users to calculate flavour observables in and beyond the Standard Model, and then test them in detail against all relevant experimental data. We describe FlavBit and its constituent physics in some detail, then give examples from supersymmetry and effective field theory illustrating how it can be used both as a standalone library for flavour physics, and within GAMBIT.