Enhancement of discrete symmetry violations in neutron-induced compound nuclei

The fundamental parity violation caused by the hadronic weak interaction is enhanced by up to 10^6 times in neutron absorption reactions of 139^La, 131^Xe, 117^Sn, and other nuclei. This enhancement can be explained by the mixing between s-wave and p-wave amplitudes of the compound nuclear state (s-p mixing model). Similarly, T-violation can also be enhanced in these systems through the same mechanism, suggesting the possibility of conducting a sensitive search for T-violation using compound nucleus reactions. The NOPTREX collaboration is planning an experiment to explore unknown T-violation by measuring the T-odd cross-section between a polarized epithermal neutron beam and a polarized target. Recently, fundamental studies for the T-violation search experiment have been conducted, including the measurement of the angular correlation of (n,gamma) reactions, enhanced P-violation, and the spin-dependent cross-section between polarized neutrons and a polarized target. In my presentation, I will provide an overview of these experiments and present several new results.