Non-Substitution Theorems for Perfect Matching Problems

WG1: Summary Structure Functions and Parton Densities

“…A study examining the PDF constraints obtained from measurements of the Drell-Yan forward-backward asymmetry at the High Luminosity LHC using xFitter was also presented [37], demonstrating that such data will provide information mostly on the sum of u and d valence quark distributions, and thus will be complementary to the measurement of the W asymmetry which constrain the difference of u and d valence quark distributions. Another study using xFitter focusing on the fits to the HERA data was presented, and a new functional form for the PDF parameterisation at the starting scale was proposed [38]. The new parameterisation gives an improved description of the HERA data.…”