标题： 阈值奇异介子光生和电产过程在SU(3)重子手征微扰理论中的研究 显示英文标题

标题： Threshold kaon photo- and electroproduction in SU(3) baryon chiral perturbation theory

摘要： 我们计算三味重重子手征微扰理论中的一循环过程$\gamma p \to K^0 \Sigma^+ , K^+ \Sigma^0, K^+ \Lambda$。 一些低能常数从单个重子性质中确定，而其他常数则通过共振饱和的方法进行估算。 总截面与阈值区域中现有的少量数据点相比较接近。 $\Lambda$和$\Sigma^0$的反冲极化的角度依赖性表现出与 ELSA 测量结果相似的大部分特征。 我们还预测了$\Sigma^+$和$< r^2_V >_{\Sigma^+} = (0.30 \pm 0.03) fm^2$的同位旋矢量电荷半径。 显示英文摘要

摘要： We calculate the processes $\gamma p \to K^0 \Sigma^+ , K^+ \Sigma^0, K^+ \Lambda$ in three flavor heavy baryon chiral perturbation theory to one loop. Some low--energy constants are fixed from single baryon properties while others are estimated by means of resonance saturation. The total cross sections are comparable with the few existing data points in the threshold region. The angular dependences of the recoil polarization of the $\Lambda$ and $\Sigma^0$ show most features of the ones measured at ELSA. We also predict the isovector charge radius of the $\Sigma^+$, $< r^2_V >_{\Sigma^+} = (0.30 \pm 0.03) fm^2$.