Beta-Gamma-Gamma Correlation inMn56: A Test of Time-Reversal Invariance

Abstract

A test of time-reversal invariance was performed by measuring the imaginary part | 8 | sin?; of the mixing ratio 8 = | 8 | e ir > between E2 and Ml reduced matrix elements through the observation of two jS-7-7 cascades in 66 Mn. The imaginary part was found to be ( -8.1±4.8) X10" 3 for the 1.81-MeV transition, and ( -7.1± 3.7)X10~3 for the 2.12-MeV transition. In order to eliminate instrumental asymmetries, the difference between the two values was taken, A(| 8 | sim?) = (1±6) X10" 3 . With an average mixing ratio for the two transitions, (\ 8 | ) = 0.23, the difference in phases is A sin?? -Arj^ (0.4±2.6) X10" 2 , giving no evidence for time-reversal violation.