Polarization observables in the processes $p + p o Theta^ + + Sigma^ + $ and $n + p o Theta^ + + Lambda^0$, in the threshold region, for any spin and parity of the $Theta^ + $-hyperon
Polarization observables in the processes $p + p o Theta^ + + Sigma^ + $ and $n + p o Theta^ + + Lambda^0$, in the threshold region, for any spin and parity of the $Theta^ + $-hyperon
复制标题
对于 $Theta^ $-超子的任何自旋和宇称，在阈值区域中 $p p o Theta^ Sigma^ $ 和 $n p o Theta^ Lambda^0$ 过程中的偏振可观测量
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
E. Tomasi
中科院分区：
文献类型：
--
作者：
M. Rekalo;E. Tomasi
摘要。利用强相互作用的对称性，如泡利原理、p不变量、总角动量守恒和同位素不变量，以模型无关的方式建立了$p + p o θ ^ + + σ ^ + $和$n + p o θ ^ + + λ ^0$过程的阈值矩阵元在近阈值区域的自旋结构，并适用于$ θ ^ + $-超子的任意自旋和宇称。我们预测了这些过程的双自旋观测值，例如微分截面对碰撞核子偏振的依赖，以及从核子束或靶到产生的$Sigma^ + $-或$Lambda^0$-超子的极化转移系数。我们证明了这些可观测值对$Theta^ + $-重子的p宇称敏感，对于其自旋的任何值。作为动力学考虑的一个例子，我们在k介子交换的框架内分析了这些反应。
Abstract.Using the symmetry properties of the strong interaction, such as the Pauli principle, the P-invariance, the conservation of the total angular momentum and isotopic invariance, we establish the spin structure of the threshold matrix elements for the processes $p + p o Theta^ + + Sigma^ + $ and $n + p o Theta^ + + Lambda^0$, in the near-threshold region, in a model-independent way, which applies to any spin and parity of the $Theta^ + $-hyperon. We predict the double-spin observables for these processes, such as the dependence of the differential cross-section on the polarizations of the colliding nucleons, and the coefficients of polarization transfer from a nucleon beam or target to the produced $Sigma^ + $- or $Lambda^0$-hyperon. We prove that these observables are sensitive to the P-parity of the $Theta^ + $-baryon, for any value of its spin. As an example of dynamical considerations, we analyzed these reactions in the framework of K-meson exchange.