Threshold Resummation and the Determination of Parton Distribution Functions

A precise knowledge of parton distribution functions (PDFs) is necessary to the accurate calculation of QCD observables initiated by hadrons. The deep inelastic scattering (DIS) and lepton pair production (LPP) processes are primary sources of information on PDFs. Recent global fits for PDFs have used DIS data from the large Bjorken $x$, moderate $Q^{2}$ region, where it is known that there are large logarithms that can be resummed using threshold resummation techniques. The purpose of this study is to investigate the effects of simultaneously including DIS and LPP threshold resummation in the determinations of PDFs. The results of multiple PDF fits corresponding to different choices of resummation methods are compared to recent results and used to discuss the implications of threshold resummation on PDF fits.