Higher-Twist Effect in Pion Parton Distribution

A higher-twist modified parton evolution equation is used to evolve the initial valence quark distributions in pions,which are derived based on light-front quantization via BLFQ collaboration.The results are consistent with the valence quark distributions of the E615 experiment,and the pion structure function of the H1 experiment.The structure function data highlight the necessity for a higher-twist modification in the small x region.Comparisons with some other models are also given.