论文标题
分析$γn\至k^+σ^ - （1385）$光生效
Analysis of the $γn \to K^+ Σ^-(1385)$ photoproduction
论文作者
论文摘要
在我们以前的工作中[物理学。修订版d $ \ bf {101} $，074025（2020）]，在有效的Lagrangian方法中调查了光生生效$γp\ to K^+σ^0（1385）$。在那里，通过考虑$ t $ channel $ k $和$ k^\ ast（892）$交易所，$ s $ s $ channel $ n $贡献，$ u $ -channel $ -CHANNEL $ -CANNEL $λ$交易所，广义联系项，最低$ s $ -Channel $ N $ N $ N $ N $ N $ N $ N $和RESUNENANCE di-songrame来构建反应振幅。发现包含$ n（1895）{1/2}^ - $，$δ（1900）{1/2}^ - $和$δ（1930）{5/2}^ - $ $ resonances是重现$ qup \ to $γp\ to k^+ k^+ n55的$差异和总跨截面数据的必不可少的必不可少的必不可少的。在目前的工作中，我们采用相同的模型来研究光增生$γn\至k^+σ^ - （1385）$，目的是了解反应机制，尤其是弄清楚$ n（1895）中的哪一种{1/2}^ - $，$，$，$δ（1900）确实有能力同时描述$ k^+σ^0（1385）$和$ k^+σ^ - （1385）$光增生反应的数据。结果表明，有关$γn\ to K^+σ^ - （1385）$的差分和总横截面和光束不对称的可用数据只能在包含$δ（1930）{5/2}^ - $ resonance的情况下才能复制。普遍的联系任期和$ t $ channel $ k $交易所被发现占主导地位的背景贡献。共振$δ（1930）{5/2}^ - $提供了所考虑的整个能量区域中最重要的贡献，并且负责总横截面中显示的凸起结构。
In our previous work [Phys. Rev. D $\bf{101}$, 074025 (2020)], the photoproduction $γp \to K^+ Σ^0(1385)$ has been investigated within an effective Lagrangian approach. There, the reaction amplitudes were constructed by considering the $t$-channel $K$ and $K^\ast(892)$ exchanges, $s$-channel $N$ contribution, $u$-channel $Λ$ exchange, generalized contact term, and a minimum number of $s$-channel $N$ and $Δ$ resonance diagrams. It was found that the inclusion of one of the $N(1895){1/2}^-$, $Δ(1900){1/2}^-$, and $Δ(1930){5/2}^-$ resonances is essential to reproduce the available differential and total cross-section data for $γp \to K^+ Σ^0(1385)$. In the present work, we employ the same model to study the photoproduction $γn \to K^+ Σ^-(1385)$, with the purpose being to understand the reaction mechanism and, in particular, to figure out which one of the $N(1895){1/2}^-$, $Δ(1900){1/2}^-$, and $Δ(1930){5/2}^-$ resonances is really capable for a simultaneous description of the data for both $K^+ Σ^0(1385)$ and $K^+ Σ^-(1385)$ photoproduction reactions. The results show that the available data on differential and total cross sections and photo-beam asymmetries for $γn \to K^+ Σ^-(1385)$ can be reproduced only with the inclusion of the $Δ(1930){5/2}^-$ resonance rather than the other two. The generalized contact term and the $t$-channel $K$ exchange are found to dominate the background contributions. The resonance $Δ(1930){5/2}^-$ provides the most important contributions in the whole energy region considered, and it is responsible for the bump structure exhibited in the total cross sections.
