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New Limit on the D Coefficient in Polarized Neutron Decay

L. J. Lising·S. R. Hwang·J. M. Adams·T. J. Bowles·M. C. Browne·T. E. Chupp·K. P. Coulter·M. S. Dewey·S. J. Freedman·B. K. Fujikawa·A. Garcia·G. L. Greene·G. L. Jones·H. P. Mumm·J. S. Nico·J. M. Richardson·R. G. H. Robertson·T. D. Steiger·W. A. Teasdale·A. K. Thompson·E. G. Wasserman·F. E. Wietfeldt·R. C. Welsh·J. F. Wilkerson
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Abstract

We describe an experiment that has set new limits on the time reversal invariance violating D coefficient in neutron beta-decay. The emiT experiment measured the angular correlation J . p_e x p_p using an octagonal symmetry that optimizes electron-proton coincidence rates. The result is D=[-0.6+/-1.2(stat)+/-0.5(syst)]x10^(-3). This improves constraints on the phase of g_A/g_V and limits contributions to T violation due to leptoquarks. This paper presents details of the experiment, data analysis, and the investigation of systematic effects.

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L. J. Lising, S. R. Hwang, J. M. Adams, T. J. Bowles, M. C. Browne, T. E. Chupp, K. P. Coulter, M. S. Dewey, S. J. Freedman, B. K. Fujikawa, A. Garcia, G. L. Greene, G. L. Jones, H. P. Mumm, J. S. Nico, J. M. Richardson, R. G. H. Robertson, T. D. Steiger, W. A. Teasdale, A. K. Thompson, E. G. Wasserman, F. E. Wietfeldt, R. C. Welsh, J. F. Wilkerson. 2000-07-19. New Limit on the D Coefficient in Polarized Neutron Decay. https://doi.org/10.1103/physrevc.62.055501

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