Measurement of ¹⁰³Rh(n,γ) reaction for T-violation search

It is known that P-violation in the (n,γ) reaction cross section of the compound nucleus, which is formed by neutron absorption into a nucleus, is enhanced by a factor of 10⁶, compared to that of proton-proton scattering. The enhancement is considered to be due to an interference between s-wave and p-wave resonances. In addition, T-violation may be enhanced for a compound nucleus in which P-violation is enhanced. We plan to search for T-violation with a polarized neutron beam and a polarized target in future. Among a number of target nuclei with large P-violation observed, we chose ¹⁰³Rh, and measured the ¹⁰³Rh(n,γ) reaction at the J-PARC/MLF BL04 beamline in June 2018.

In this presentation, we will report the analysis status of the γ-ray energy distribution measured with Germanium detectors and the neutron resonance distribution.