论文标题
用核子和杜特龙靶的衍射两烯膜电源
Diffractive two-meson electroproduction with a nucleon and deuteron target
论文作者
论文摘要
两个被较大速度差距分隔的介体的衍射电或照相产生以非常特定的方式访问广义的Parton分布（GPD）。首先，这些反应允许通过选择一种生成的载体中的媒介中的一种可以横向极化来轻松访问手性trant码夸克gpd。其次，它们仅对所谓的ERBL区域敏感，在该区域中，GPD并没有受到前向夸克分布的约束。第三，偏度参数$ξ$与bjorken $ x_ \ text {bj} $变量无关，而与速度差距的大小有关。我们分析了不同的通道（$ρ_l^0 \，ρ_{l/t}，ρ^0_l \，ω__{l/t} $和$ρ^0_l \，π$，π$生产）和deuteron targets。分析在运动域中进行，其中从光子到衍射产生的媒介中的大动量转移引入了硬尺度（交换硬波梅隆的虚拟性）。这使得在GPD的共线分解框架中对过程的耐药部分的描述。我们表明，非偏置横截面在很大程度上取决于核子的手性和手性夸克分布的参数化，以及梅森分布幅度的形状。该速率显示在未来电子离子对撞机的能力范围内。
The diffractive electro- or photo-production of two mesons separated by a large rapidity gap gives access to generalized parton distributions (GPDs) in a very specific way. First, these reactions allow to easily access the chiral-odd transversity quark GPDs by selecting one of the produced vector meson to be transversely polarized. Second, they are only sensitive to the so-called ERBL region where GPDs are not much constrained by forward quark distributions. Third, the skewness parameter $ξ$ is not related to the Bjorken $x_\text{Bj}$ variable, but to the size of the rapidity gap. We analyze different channels ($ρ_L^0\,ρ_{L/T}, ρ^0_L\,ω_{L/T}$ and $ρ^0_L\,π$ production) on nucleon and deuteron targets. The analysis is performed in the kinematical domain where a large momentum transfer from the photon to the diffractively produced vector meson introduces a hard scale (the virtuality of the exchanged hard Pomeron). This enables the description of the hadronic part of the process in the framework of collinear factorization of GPDs. We show that the unpolarized cross sections depend very much on the parameterizations of both chiral-even and chiral-odd quark distributions of the nucleon, as well as on the shape of the meson distribution amplitudes. The rates are shown to be in the range of the capacities of a future electron-ion collider.
