Azimuthal Asymmetry In SIDIS Wish Longitudinally Polarized

In the last century, there had been a great increase in our knowledge about the structure of materials, like proton, electron, quark and gluon. Actually, such studies, for example, the appearance of quark and parton model, have aroused great interest at that time, and also been at the cutting edge of the present Physics. In practice, some useful methods have been fruitful developed, including DIS and SIDIS between leptons and nuclei, through which lots of inner information can be revealed. Especially, there are some very interesting processes that are related to the asymmetry of azimuth and spin in the final state, which are the concerns of our work.This paper is to use the high twist method to study the azimuthal asymmetry in unpolarized and polarized SIDIS. This paper is divided into three parts, in the Chapterâ…¡, we introduce a simple way to calculate the azimuthal asymmetry in unpolarized SIDIS, in the face this method is the expansion of the parton model. At the same time we use this method in the case of polarized azimuthal asymmetry SIDIS process. In the Chapterâ…¢, we calculated under the circumstances azimuthal asymmetry in unpolarized SIDIS process with the method of collinear expansion in strict high twist factor of QCD. In the Chapter IIII we use the calculation method of Chapterâ…¢to study the azimuthal asymmetry in the process of polarization case SIDIS. In the end, we give our summary and prospect.