arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1801.06264hep-phhep-exhep-latnucl-exnucl-th
收藏

强子层析成像及其对强子引力半径的应用

Hadron tomography and its application to gravitational radii of hadrons

S. Kumano, Qin-Tao Song, O. V. Teryaev

摘要:

强子层析成像已经被研究的三维结构函数,如广义部分子分布(GPD)和广义分布振幅(GDA)。GDA是GPD的$s$ - $t$交叉量,两个函数都探测强子的引力形状因子。我们通过分析Belle双光子过程$γ^* γ\to π^0 π^0$的微分截面数据确定了π介子GDA。由所测得的GDA,我们计算了π介子的类时引力形状因子,并利用色散关系将其转换为类空形状因子。这些重力形状因子$Θ_1$和$Θ_2$分别表示机械(压力、剪切力)和重力质量(或能量)分布。然后,引力半径计算的π介子的形状因子,并与π介子电荷半径进行了比较。我们解释了引力物理学的新领域可以在夸克和胶子的微观水平上发展。

英文摘要:

Hadron tomography has been investigated by three-dimensional structure functions, such as generalized parton distributions (GPDs) and generalized distribution amplitudes (GDAs). The GDAs are $s$-$t$ crossed quantities of the GPDs, and both functions probe gravitational form factors for hadrons. We determined the pion GDAs by analyzing Belle data on the differential cross section for the two-photon process $γ^* γ\to π^0 π^0$. From the determined GDAs, we calculated timelike gravitational form factors of the pion and they were converted to the spacelike form factors by using the dispersion relation. These gravitational form factors $Θ_1$ and $Θ_2$ indicate mechanical (pressure, shear force) and gravitational-mass (or energy) distributions, respectively. Then, gravitational radii are calculated for the pion from the form factors, and they are compared with the pion charge radius. We explain that the new field of gravitational physics can be developed in the microscopic level of quarks and gluons.

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。

↑