arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1406.7709hep-ph
收藏

从维格纳分布看夸克轨道运动

Quark orbital motions from Wigner distributions

Tianbo Liu

摘要:

本文研究了光锥旁观者模型中夸克的维格纳分布。标量和轴矢量观众都包括在内。从夸克-旁观者-核子的有效顶点出发,导出了光锥波函数,并通过调整能量守恒因子的幂次,将其推广。通过引入相对相位的光锥振幅,考虑到规范链接,和相位估计从一个胶子交换相互作用。从维格纳分布出发,计算了描述横坐标和横动量之间的关联以及夸克轨道运动的混合分布。我们发现在极化质子中,在小$x$区域,$u$夸克和$d$夸克都有正的轨道角动量,而在大$x$区域,$d$夸克的轨道角动量发生了变化.此外,还发现了不同偏振态下维格纳分布之间的模型关系。

英文摘要:

We investigate quark Wigner distributions in a light-cone spectator model. Both the scalar and the axial-vector spectators are included. The light-cone wave functions are derived from effective quark-spectator-nucleon vertex and then generalized by adjusting the power of energy denominators. The gauge link is taken into account by introducing relative phases to the light-cone amplitudes, and the phases are estimated from one gluon exchange interactions. The mixing distributions, which describe the correlation between transverse coordinate and transverse momentum and represent quark orbital motions, are calculated from the Wigner distributions. We find both $u$ quark and $d$ quark have positive orbital angular momentum in a polarized proton at small $x$ region, but a sign change is observed at large $x$ region for the $d$ quark. Besides, some model relations between Wigner distributions with different polarization configurations are found.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑