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A New Limit on Time-Reversal Violation in Beta Decay



Hans P. Mumm, T E. Chupp, K P. Coulter, R L. Cooper, S J. Freedman, B. K. Fujikawa, A. Garcia, Gordon L. Jones, Jeffrey S. Nico, Alan K. Thompson, C A. Trull, J. F. Wilkerson, F. E. Wiefeldt


We report the results of an improved determination of the triple correlation DP • (p_e × p_v) that can be used to limit possible time-reversal invariance in the beta decay of polarized neutrons and constrain extensions to the Standard Model. Our result is D = (-0.96 ± 1.89(stat) ± 1.01(sys)) × 10e-4. The corresponding phase between g_A and g_V is 180.013 ± 0.028 degrees (68% confidence level). This result represents the most sensitive measurement of D in nuclear beta decay.
Physical Review Letters


baryon asymmetry, neutron decay, symmetries, time-reversal


Mumm, H. , Chupp, T. , Coulter, K. , Cooper, R. , Freedman, S. , Fujikawa, B. , Garcia, A. , Jones, G. , Nico, J. , Thompson, A. , Trull, C. , Wilkerson, J. and Wiefeldt, F. (2012), A New Limit on Time-Reversal Violation in Beta Decay, Physical Review Letters (Accessed February 26, 2024)
Created September 2, 2012, Updated February 19, 2017