Decay Characteristics of Neutron Excess Copper Nuclei

The properties of neutron excess copper nuclei are determined utilizing a single-particle model. The single particle model calculations include alpha, beta, positron, electron capture, and spontaneous fission decay modes. Neutron emission decay modes that have short half-lives are not readily determined by the model. However, estimates of the neutron decay mode were evaluated using the methodology of Chowdhury et al. Using that model, spontaneous neutron emission is predicted to occur in the range of A = 91 – 93. The Japanese Nuclear Data Compilation calculations terminate their calculations at A = 87. Given these results, single-particle model calculations are extended to encompass these values, and were extended to A = 95.

Single particle model calculations predict that A = 82 – 95 neutron excess copper systems form bound systems that have limiting beta decay half-lives in the range of 1.40 – 44.3 ms. Model half-life results for the A = 82 – 87 copper nuclei are within a factor of about two of the predictions of the Japanese Nuclear Data Compilation calculations.