arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1702.01477nucl-thhep-lathep-phnucl-ex
收藏

张量极化氘质子-氘Drell-Yan过程的自旋不对称性

Spin asymmetry for proton-deuteron Drell-Yan process with tensor-polarized deuteron

S. Kumano, Qin-Tao Song

摘要:

氘核的张量结构可以通过深度非弹性散射和Drell-Yan过程来研究,以夸克和胶子自由度来理解它。它探讨了有趣的功能,包括D波的贡献,在氘核。在带电轻子DIS中,扭转2结构函数$b_1$和$b_2$用张量极化的部分子分布函数(PDF)表示。我们注意到,$b_1$的HERMES实验测量似乎与传统的理论预测有很大不同。这种令人困惑的情况应该在不久的将来得到显著改善,通过批准的实验来测量$b_1$在JLab。另一方面,张量极化的PDF,特别是反夸克分布,可以测量的自旋不对称性的Drell-Yan过程与张量极化的氘核在费米实验室。在这项工作中,我们估计张量极化不对称的费米实验室Drell-Yan实验通过使用参数化的张量极化PDF来解释的HERMES $b_1$数据。得到的自旋不对称性通常是百分之几的数量级,它们可以通过Fermilab-E1039实验测量。由于张量极化的反夸克分布将在解决这个难题中发挥重要作用,因此需要在费米实验室和其他强子设施上对Drell-Yan实验进行进一步的理论和实验努力。

英文摘要:

Tensor structure of the deuteron can be studied by deep inelastic scattering and Drell-Yan process to understand it in terms of quark and gluon degrees of freedom. It probes interesting features in the deuteron including a D-wave contribution. In the charged-lepton DIS, twist-two structure functions $b_1$ and $b_2$ are expressed by tensor-polarized parton distribution functions (PDFs). We note that the HERMES experimental measurement of $b_1$ seems to be much different from a conventional theoretical prediction. This puzzling situation should be significantly improved in the near future by an approved experiment to measure $b_1$ at JLab. On the other hand, the tensor-polarized PDFs, especially antiquark distributions, could be measured by spin asymmetries in the Drell-Yan process with a tensor-polarized deuteron at Fermilab. In this work, we estimate tensor-polarization asymmetries for the Fermilab Drell-Yan experiment by using a parametrization for the tensor-polarized PDFs to explain the HERMES $b_1$ data. Obtained spin asymmetries are typically a few percent order and they could be measured by the Fermilab-E1039 experiment. Since the tensor-polarized antiquark distributions will play an important role to solve the puzzle, further theoretical and experimental efforts are needed toward the Drell-Yan experiment at Fermilab and other hadron facilities.

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。

↑