Applications of a nonlinear evolution equation II: The EMC effect

Abstract

The EMC effect is studied by using the DGLAP equation with the ZRS corrections and minimum number of free parameters, where the nuclear shadowing effect is a dynamical evolution result of the equation, the nucleon swelling and Fermi motion in the nuclear environment deform the input parton distributions. Parton distributions of both proton and nucleus are predicted in a unified framework. We show that the parton recombination as a higher twist correction plays an essential role in the evolution of parton distributions either of proton or nucleus. We find that the nuclear anti-shadowing contributes a part of enhancement of the ratio of the structure functions around x ~ 0.1, while the other part origins from the deformation of the nuclear valence quark distributions. In particular, the nuclear gluon distributions are dynamically predicted, which are important information for the recherche of the high energy nuclear physics.