论文标题
核子的电荷半径是从其风味依赖的狄拉克形式的
Charge radii of the nucleon from its flavor dependent Dirac form factors
论文作者
论文摘要
在首先在轻锥形框架配方中,在电荷对称性下对这些形式的质量分解后,我们从质子和中子弹性形式的全局分析中确定了质子和中子电荷半径。然后,我们提取了依赖性夸克分布的横向均方根半径。反过来,它们以与质子和中子电荷半径无关的方式相关,但允许我们考虑到有限但高动量转移的数据后反冲核子的运动效应。在质子的情况下,我们发现$ \ langle r_p \ rangle = 0.852 \ pm0.002 _ {\ rm(stat。)} \ pm0.009 _ {\ rm(syst。 \ cite {pohl:2010,antog2013}。当前方法基于副本测量值的$ \ langle r_p \ rangle $提取的精度提高。此外,我们发现在不同的电子散射测量测量中确定$ \ langle r_p \ rangle $在$ \ langle r_p \ rangle $中没有差异,所有这些测量都利用了当前的提取方法,导致价值与最小的$ \ langle r_p \ r_p \ rangle r_p \ rangle $ frock cractional cretaction \ langle r_p \ rangle r_p \ rangle $ sctipturection \ ciete \ cite \ cite \ cite c。关于中子情况,过去的结果仅依赖于中子电子散射长度测量值,这些测量值低估了提取技术固有的潜在系统不确定性。利用当前的方法,我们基于核子形态数据进行了首次提取中子电荷半径,我们发现$ \ langle r_n^2 \ rangle = -0.122 \ pm0.004 _ {\ rm(stat。stat。
We have determined the proton and the neutron charge radii from a global analysis of the proton and the neutron elastic form factors, after first performing a flavor decomposition of these form factors under charge symmetry in the light cone frame formulation. We then extracted the transverse mean-square radii of the flavor dependent quark distributions. In turn, these are related in a model-independent way to the proton and neutron charge radii but allow us to take into account motion effects of the recoiling nucleon for data at finite but high momentum transfer. In the proton case we find $\langle r_p \rangle = 0.852 \pm0.002_{\rm (stat.)} \pm0.009_{\rm (syst.)}~({\rm fm})$, consistent with the proton charge radius obtained from muonic hydrogen spectroscopy \cite{pohl:2010,antog2013}. The current method improves on the precision of the $\langle r_p \rangle$ extraction based on the form factor measurements. Furthermore, we find no discrepancy in the $\langle r_p \rangle$ determination among the different electron scattering measurements, all of which, utilizing the current method of extraction, result in a value that is consistent with the smallest $\langle r_p \rangle$ extraction from the electron scattering measurements \cite{Xiong:2019umf}. Concerning the neutron case, past results relied solely on the neutron-electron scattering length measurements, which suffer from an underestimation of underlying systematic uncertainties inherent to the extraction technique. Utilizing the present method we have performed the first extraction of the neutron charge radius based on nucleon form factor data, and we find $\langle r_n^2 \rangle = -0.122 \pm0.004_{\rm (stat.)} \pm0.010_{\rm (syst.)}~({\rm fm}^2)$.