arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2401.04080hep-lathep-ph
收藏

使用扭曲质量费米子的π介子和K介子的广义形状因子

Generalized form factors of the pion and kaon using twisted mass fermions

Joseph Delmar, Constantia Alexandrou, Simone Bacchio, Ian Cloët, Martha Constantinou, Giannis Koutsou

AI总结:

本文使用动量增强的介子态和扭曲质量费米子,更新了π介子和K介子PDF与GPD的Mellin矩格点计算,提取了荷与广义形状因子,并详细研究了激发态、离散化和体积效应。

摘要:

我们更新了使用动量增强的介子态对π介子和K介子的PDF和GPD的Mellin矩的格点计算。特别地,我们重点关注标量和张量局部算符,以及带有最多三个协变导数的矢量算符的计算。相应的矩阵元使我们能够提取标量和张量荷,以及 $n=1,2,3$ 的 $\langle x^n \rangle$。此外,我们在初末态介子之间引入动量转移,从而得到标量、矢量和张量形状因子,以及多达三个协变导数的广义形状因子。上述结果使用两组具有clover改进的最大扭曲质量费米子系综获得,包含两个简并轻夸克、一个奇夸克和一个粲夸克 $(N_f=2+1+1)$,格距分别为 0.093 fm 和 0.081 fm。这些系综的π介子质量约为 260 MeV。我们通过分析源-_sink时间间隔的四个值(1.12 - 1.67 fm)来研究激发态效应。我们还检查了离散化和体积效应。格点数据经过非微扰重整化,结果以 2 GeV 尺度下的 MS 方案呈现。

英文摘要:

We present an update on our lattice calculations of the Mellin moments of PDFs and GPDs for the pion and kaon, using momentum-boosted meson states. In particular, we focus on the calculation of the scalar and tensor local operators, and the vector operator with up to three-covariant derivatives. The corresponding matrix elements allow us to extract the scalar and tensor charges, as well as $\langle x^n \rangle$ with $n=1,2,3$. In addition, we introduce momentum transfer between the initial and final meson state that leads to the scalar, vector, and tensor form factors, and the generalized form factors up to three covariant derivatives. The above results are obtained using two ensembles of maximally twisted mass fermions with clover improvement with two degenerate light, a strange, and a charm quark $(N_f=2+1+1)$ at lattice spacings of 0.093 fm and 0.081 fm. The pion mass of the ensembles is about 260 MeV. We study excited-states effects by analyzing four values of the source-sink time separation (1.12 - 1.67 fm). We also examine discretization and volume effects. The lattice data are renormalized non-perturbatively, and the results are presented in the MS scheme at a scale of 2 GeV.

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。

↑