Application of the Kimber-Martin-Ryskin and Martin-Ryskin-Watt unintegrated parton distributions to the EMC ratio of a ~6Li nucleus in the k_t-factorization framework

摘要

In the present work, it is intended to calculate the unintegrated parton distribution functions (UPDFs) of the ~6Li nucleus, which depend not only on the longitudinal momentum fraction x (the Bjorken variable) and the factorization scale μ of partons, but also on their transverse momentum (k_t). Therefore, the KMR and MRWprocedures are applied to generate the k_t-dependent parton distributions from the familiar integrated parton densities (PDFs), which were determined in our recent related work, using the constituent quark exchange model (CQEM) for the ~6Li nucleus. Then, the resulting UPDFs of ~6Li are compared with the UPDFs of free proton from our previous work. Afterwards, from the kt-factorization formalism, the structure function (SF) of the ~6Li nucleus is computed to extract its European Muon Collaboration (EMC) ratio. The results are compered with those generated from the ~6Li nucleus PDFs and the available NMC experimental data. It is observed that, especially in the small x region, where the k_t dependence of partons is important in the calculations of the hadron structure functions, the present EMC ratios are extremely improved, compared with those of our previous work, and show an excellent agreement with the NMC experimental data.