Parton Densities at the LHC

TL;DR

This paper reviews the current status of parton density functions (PDFs) and their uncertainties at the LHC, highlighting methods to constrain PDFs using LHC data and the advantages of PDF reweighting techniques for uncertainty estimation.

Contribution

It introduces the PDF reweighting technique for rapid estimation of PDF uncertainties in Monte Carlo simulations at the LHC.

Findings

PDF uncertainties significantly impact LHC physics analyses

PDF reweighting allows quick uncertainty estimates

Methods to constrain PDFs using LHC data are discussed

Abstract

This contribution to the Italian "Workshop sui Monte Carlo, la Fisica e le Simulazioni a LHC", held at LNF, Frascati, in February, May and October 2006, summarises the status of parton density functions (PDF's) and the impact of their uncertainties on the LHC physics. Emphasis is given to methods of contraining PDF's using LHC data. Moreover, the advantages of the so-called PDF reweighting technique, which enables to quickly estimate PDF uncertainties with Monte Carlo events, are also presented.