Impact of low-energy data on global fits of PDFs

Traditional global fits for parton distribution functions (PDFs) use cuts on $Q$ and $W$ in deeply inelastic lepton-nucleon scattering (DIS) to eliminate regions where target mass corrections and higher twist contributions are important. Such cuts typically limit the coverage in $x$ to $x < 0.7$, which is also the range covered by most high energy DIS experiments. In order to constrain the PDFs at larger values of $x$, one can relax the cuts imposed on $Q$ and $W$ and make use of lower energy data. This necessitates treating the target mass corrections and higher twist contributions in the fits. Furthermore, the separation of the $u$ and $d$ PDFs requires the use of nuclear targets - typically deuterium - which requires the inclusion of corrections for nuclear effects. This is particularly important in the large-$x$ region. In this talk I will review some recent efforts to include low-energy data in global fits and discuss the resulting PDFs.