论文标题
核中价值夸克的残余平均场模型
Residual Mean Field Model of Valence Quarks in the Nucleon
论文作者
论文摘要
我们基于核子内部价值夸克的平均场相互作用，开发了一个非扰动模型（PDFS）。该模型的主要动机是获得价值夸克的平均场描述，以研究产生PDF的高$ x $尾巴的短距离夸克Quark互动。该模型基于价值三夸克群和核中残留系统的分离。然后，在有效的轻正图方法中计算了核子结构函数，该方法引入了非扰动的轻正价夸克和残留波函数。在模型中，在$ xq_v（x）$的峰值之间获得了一个新的关系，价格为$ xq_v（x）$的分布和剩余系统的有效质量，$ m_r $，形式为：$ x_ {p} \ of 4}（1-}（1-}（1- {1- {m_r \ fiver m_n} $）这种关系解释了D型和U Quark分布的残留质量的预期差异D-和U夸克的峰位置的差异。该模型的参数是通过将计算出的价夸克分布拟合到现象学PDF来固定的。这使我们能够估计价D和U夸克的重型和势头总和规则中的总体平均现场贡献。最后，价值3Q群集和残留系统的非扰动波函数的评估参数可用于计算其他数量，例如核子形态，广义partononic和横向动量分布。
We develop a non-perturbative model for valence parton distribution functions (PDFs) based on the mean field interactions of valence quarks in the nucleonic interior. The main motivation for the model is to obtain a mean field description of the valence quarks as a baseline to study the short range quark-quark interactions that generate the high $x$ tail of PDFs. The model is based on the separation of the valence three-quark cluster and residual system in the nucleon. Then the nucleon structure function is calculated within the effective light-front diagrammatic approach introducing nonperturbative light-front valence quark and residual wave functions. Within the model a new relation is obtained between the position, $x_p$, of the peak of $xq_V(x)$ distribution of the valence quark and the effective mass of the residual system, $m_R$, in the form: $x_{p} \approx {1\over 4} (1-{m_R\over m_N})$ at starting $Q^2$. This relation explains the difference in the peak positions for d- and u- quarks through the expected difference of residual masses for valence d- and u- quark distributions. The parameters of the model are fixed by fitting the calculated valence quark distributions to the phenomenological PDFs. This allowed us to estimate the overall mean field contribution in baryonic and momentum sum rules for valence d- and u- quarks. Finally, the evaluated parameters of the non-perturbative wave functions of valence 3q-cluster and residual system can be used in calculation of other quantities such as nucleon form factors, generalized partonic and transverse momentum distributions.
