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arXiv · 0902.1194

The D coefficient in neutron beta decay in effective field theory

Shung-ichi Ando·Judith A. McGovern·Toru Sato
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Abstract

In this paper we explore the time-reversal-odd triple-correlation coefficient in neutron beta decay, the so-called "D coefficient", using heavy-baryon effective field theory with photon degrees of freedom. We find that this framework allows us to reproduce the known results for the contribution which comes from final-state interactions, and also to discuss higher-order corrections. In particular we are able to show that in the heavy-baryon limit all electromagnetic contributions vanish. By calculating the leading correction to the known result, we give a final expression which is accurate to better than 1%. Hence we extend downwards the range over which the D coefficient could be used to explore time-violation from new physics.

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Shung-ichi Ando, Judith A. McGovern, Toru Sato. 2009-05-01. The D coefficient in neutron beta decay in effective field theory. https://doi.org/10.1016/j.physletb.2009.04.088

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