Direct reaction test of T violation in 2 MeV neutron scattering from aligned 165Ho

The parity-even time-reversal-odd five-fold correlation has been studied in 2 MeV polarized neutron transmission through a rotating, cryogenically-aligned 165Ho target. The analyzing power was found to be (1 ± 6) × 10−4, consistent with time reversal invariance. We obtain a bound of 5 × 10−3 for αT, the ratio of T-odd to T-even couplings in the effective N−N interaction.