HERAFitter, Open Source QCD Fit Project

TL;DR

HERAFitter is an open-source software framework designed for determining proton parton distribution functions (PDFs) using diverse experimental data and theoretical models in QCD, supporting various analysis methods.

Contribution

It introduces a comprehensive, flexible platform that integrates multiple PDF determination techniques and theoretical options for QCD analyses, enhancing research capabilities.

Findings

Supports a wide range of experimental data types.

Includes multiple methods for PDF fitting and visualization.

Enables study of new collider measurements' impact on PDFs.

Abstract

HERAFitter is an open-source package that provides a framework for the determination of the parton distribution functions (PDFs) of the proton and for many different kinds of analyses in Quantum Chromodynamics (QCD). It encodes results from a wide range of experimental measurements in lepton-proton deep inelastic scattering and proton-proton (proton-antiproton) collisions at hadron colliders. These are complemented with a variety of theoretical options for calculating PDF-dependent cross section predictions corresponding to the measurements. The framework covers a large number of the existing methods and schemes used for PDF determination. The data and theoretical predictions are brought together through numerous methodological options for carrying out PDF fits and plotting tools to help visualise the results. While primarily based on the approach of collinear factorisation, HERAFitter also provides facilities for fits of dipole models and transverse-momentum dependent PDFs. The package can be used to study the impact of new precise measurements from hadron colliders. This paper describes the general structure of HERAFitter and its wide choice of options.