Interference effect between neutron direct and resonance capture reactions for neutron-rich nuclei

Abstract

Interference effect of neutron capture cross section between the compound and direct processes is investigated. The compound process is calculated by resonance parameters and the direct process by the potential model. The interference effect is tested for neutron-rich ⁸²Ge and ¹³⁴Sn nuclei relevant to r-process and light nucleus ¹³C which is neutron poison in the s-process and produces long-lived radioactive nucleus ¹⁴C (T_1/2 = 5700 y). The interference effects in those nuclei are significant around resonances, and low energy region if s-wave neutron direct capture is possible. Maxwellian averaged cross sections at kT = 30 and 300 keV are also calculated, and the interference effect changes the Maxwellian averaged capture cross section largely depending on resonance position.