Twist-4 contributions to semi-inclusive deeply inelastic scatterings with polarized beam and target
Twist-4 contributions to semi-inclusive deeply inelastic scatterings with polarized beam and target
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DOI：
10.1103/physrevd.95.074017
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发表时间：
2016-11
影响因子：
5
通讯作者：
Shu-yi Wei;Yu-kun Song;Kai-bao Chen;Z. Liang
中科院分区：
文献类型：
--
作者：
Shu-yi Wei;Yu-kun Song;Kai-bao Chen;Z. Liang
在pQCD的树形能级上，我们首次给出了半包含深度非弹性散射e^-N到e^-Qx的完全扭转-4结果。利用共线展开后的公式进行了计算，其中考虑了多重胶子散射，并以系统的方式自动获得了规范联系。结果表明，对应于8个扭曲-2横向动量相关的部分子分布函数的所有8个扭曲-2结构函数都有扭曲-4的贡献。这样的高扭转效应可能是非常显著的，因此对从e^-N到e^-HX$的不对称数据中提取这些三维部分子分布函数具有重要的影响。我们还建议了一种近似的方法来粗略地估计这种较高的扭曲贡献。
We present for the first time the complete twist-4 result for the semi-inclusive deeply inelastic scattering $e^- N \to e^-qX$ with polarized electron and proton beams at the tree level of pQCD. The calculations have been carried out using the formulism obtained after collinear expansion where the multiple gluon scattering are taken into account and gauge links are obtained automatically in a systematical way. The results show in particular that there are twist-4 contributions to all the eight twist-2 structure functions for $e^- N \to e^-hX$ that correspond to the eight twist-2 transverse momentum dependent parton distribution functions. Such higher twist effects could be very significant and therefore have important impacts on extracting these three-dimensional parton distribution functions from the asymmetry data on $e^- N \to e^-hX$. We suggest also an approximate way for a rough estimation of such higher twist contributions.