P-a Collisions The Nuclear Effects In Drell-yan Process

In protron-protron collisions, the interactions between quark-gluon that make up colliding nucleons can be learned. In nucleus-nucleus collisions, physical scientists hope to find a signal for the existence of the deconfining phase of QCD, the quark-gluon plasma. In protron-nucleus collistrons, it is hoped to gain more information about the modification of the parton distribution functions in the nuclei, and to learn the space-time development of the strong interaction during its early stages. We can gain the parton distribution functions in the nuclei and the energy loss of the fast quark and gluon moving through the nuclei. Understanding the initial stages of ultra-relativistic heavy-ion collisions is of utmost importance in order to understand the outcome of the high energy heavy-ion experiments, such as the BNL relativistic heavy-ion collider (RHIC) and the CERN large hadron collider (LHC).The Drell-Yan process in p-A collisions is similar to deep inelastic scattering process. It is an also ideal tool to study the nuclear parton distribution. The quark energy loss of fast quarks in nuclear matter is another nuclear effect apart from the nuclear effects on the parton distribution as in deep inelastic scattering process. If the fast quark energy loss in nuclear Drell-Yan process has an obvious effect on nuclear Drell-Yan process differential cross section as a function of the parton momentum fraction target, the nuclear Drell-Yan process could be used difficulty in studying the nuclear sea quark distribution.In the paper, the nuclear Drell-Yan differential cross section ratios are calculated for 800GeV proton incident on D and W by considering quark energy loss effect with the nuclear parton distributions from fitting l- A deep inelastic scattering experimental data. It is found that the energy loss effect can obviously impact on the nuclear Drell-Yan differential cross section. With considering the existence of quark energy-loss effect, the energy-loss effect should be taken into account for extractions of nuclear sea quark distribution functions from the nuclear Drell-Yan process.