Application of the KMR and MRW unintegrated parton distributions to the EMC ratio of $^6{Li}$ nucleus in the $k_t$-factorization framework

Abstract

In the present work, it is intended to calculate the unintegrated parton distribution functions (UPDFs) of the $^6{Li}$ nucleus, which depend not only on the longitudinal momentum fraction $x$ (the Bjorken variable) and the factorization scale $\mu$ of partons, but also on their transverse momentum ($k_t$). Therefore, the KMR and MRW procedures 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 $^6{Li}$ are compared with the UPDFs of free proton from our previous work. Afterwards, from the $k_t$-factorization formalism, the structure function (SF) of $^6{Li}$ 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 are 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.