A numerical study of the anisotropic distribution of γ-ray emission from oriented 129m,131m,133m Xe

Spin-polarized radioactive nuclei emit radioactive decay products in an anisotropic manner that is characteristic of their degree of nuclear orientation. This property can be utilized for nuclear magnetic resonance spectroscopy and imaging. In this manuscript, we present Python and MATLAB numerical simulations that investigate the angular distribution and measurable asymmetry of γ -ray emission from spin-oriented nuclei of the metastable isotopes 129 m , 131 m , 133 m Xe. We examine several cases that represent different degrees of spin alignment and detection geometries. The results of our simulations provide a benchmark for experiments that use γ -decay anisotropy, such as the GAMMA-MRI project, which aims to develop a novel medical-imaging technique combining the strengths of magnetic resonance and nuclear medicine imaging.