论文标题
中子极化转移，$ c_ {x'}^n $，in $π^+$ $ photoproduction of proton
Neutron polarisation transfer, $C_{x'}^n$, in $π^+$ photoproduction off the proton
论文作者
论文摘要
我们报告了可观察到的双极化的第一个测量，$ c_ {x'} $，以$π^+$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $。 $ c_ {x'} $双偏光可观察到的可观察到从圆极化光子束向后退中子的转移。撞击液体氘靶细胞上的MAMI圆形光子光束，在水晶球量热计中检测到反应产物。围绕目标周围的辅助设备提供了跟踪，颗粒识别和后座核子极化的测定。 $ c_ {x'} $可观察到的光子能量800-1400 MEV确定，为旨在阐明核子共振的光谱和特性的模型提供了新的约束。这是该反应可观察到的可观察到的任何极化组的首次确定，从而对基于部分波浪分析的当前解决方案进行了有价值的约束和系统的检查。
We report a first measurement of the double-polarisation observable, $C_{x'}$, in $π^+$ photoproduction off the proton. The $C_{x'}$ double-polarisation observable represents the transfer of polarisation from a circularly polarised photon beam to the recoiling neutron. The MAMI circularly polarised photon beam impinged on a liquid deuterium target cell, with reaction products detected in the Crystal Ball calorimeter. Ancillary apparatus surrounding the target provided tracking, particle identification and determination of recoil nucleon polarisation. The $C_{x'}$ observable is determined for photon energies 800-1400 MeV, providing new constraints on models aiming to elucidate the spectrum and properties of nucleon resonances. This is the first determination of any polarisation observable from the beam-recoil group of observables for this reaction, providing a valuable constraint and systematic check of the current solutions of partial wave analysis based theoretical models.
