论文标题
$ n（1535）$共振的达利兹衰变的协变模型
Covariant model for the Dalitz decay of the $N(1535)$ resonance
论文作者
论文摘要
我们为$γ^\ ast n \ to N（1535）$转换开发了一个协变量模型，该区域是正方形动量传递$ q^2 $的区域。我们的起点是由空格类运动区域中数据约束的协变量夸克模型（$ q^2 = -q^2> 0 $）。该模型用于估计价夸克对过渡形式的贡献，并且在中间和大$ q^2 $上获得了对狄拉克形式的公平描述。对于Pauli的形式，有证据表明，除了夸克核的贡献之外，梅森云效应也有很大的贡献。将夸克核模型与对介子云效应的有效描述相结合，我们得出了可以将太空型数据的参数化，可以将协变量扩展到时期区域。这一扩展使我们能够估算$ n（1535）$共振的Dalitz衰减宽度，以及其他可观察物。我们的计算可以帮助解释Hades（$ PP $碰撞等）的本实验。
We develop a covariant model for the $γ^\ast N \to N(1535)$ transition in the timelike kinematical region, the region where the square momentum transfer $q^2$ is positive. Our starting point is the covariant spectator quark model constrained by data in the spacelike kinematical region ($Q^2 = -q^2 >0$). The model is used to estimate the contributions of valence quarks to the transition form factors, and one obtains a fair description of the Dirac form factor at intermediate and large $Q^2$. For the Pauli form factor there is evidence that beyond the quark-core contributions there are also significant contributions of meson cloud effects. Combining the quark-core model with an effective description of the meson cloud effects, we derive a parametrization of the spacelike data that can be extended covariantly to the timelike region. This extension enabled us to estimate the Dalitz decay widths of the $N(1535)$ resonance, among other observables. Our calculations can help in the interpretation of the present experiments at HADES ($pp$ collisions and others).
