论文标题
baryon共振在$π^-p \ to ne^+e^ - $反应中的作用
Role of baryon resonances in the $π^-p \to ne^+e^-$ reaction within an effective-Lagrangian model
论文作者
论文摘要
We present a study of the reaction $π^-p \to ne^+e^-$ for $\sqrt{s}=1.49\,\textrm{GeV}$, including non-resonant Born terms and contributions of the $N(1440)$, $N(1520)$, $N(1535)$ resonances ($R$), using an effective-Lagrangian model, which we extended by a $rnρ$顶点功能处的现象学阶段因子。我们给出了差异横截面$dσ/dm $和腐烂到Lepton对的虚拟光子的旋转密度矩阵元素的预测。在研究的能源范围内，横截面由BORN和$ n（1520）$贡献主导。
We present a study of the reaction $π^-p \to ne^+e^-$ for $\sqrt{s}=1.49\,\textrm{GeV}$, including non-resonant Born terms and contributions of the $N(1440)$, $N(1520)$, $N(1535)$ resonances ($R$), using an effective-Lagrangian model, which we extended by a phenomenological phase factor at the $RNρ$ vertex function. We give predictions for both the differential cross section $dσ/dm$ and the spin density matrix elements of the virtual photon that decays into the lepton pair. In the studied energy range, the cross section is dominated by the Born and $N(1520)$ contributions.
