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arXiv · 1403.2447

Probing TeV scale physics in precision UCN decays

Rajan Gupta·Tanmoy Bhattacharya·Anosh Joseph·Saul D. Cohen·Huey-Wen Lin
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Abstract

We present the calculation of matrix elements of iso-vector scalar, axial and tensor charges between a neutron and a proton state on dynamical $N_f=2+1+1$ HISQ configurations generated by the MILC Collaboration using valence clover fermions. These matrix elements are needed to probe novel scalar and tensor interactions in neutron beta-decay that can arise in extensions to the Standard Model at the TeV scale. Results are presented at one value of the lattice spacing, $a=0.12$ fm, and two values of light quarks corresponding to $M_\pi=310$ and $220$ MeV. We discuss two sources of systematic errors, contribution of excited states to these matrix elements and the renormalization constants, and the efficacy of methods used to control them.

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Rajan Gupta, Tanmoy Bhattacharya, Anosh Joseph, Saul D. Cohen, Huey-Wen Lin. 2014-03-11. Probing TeV scale physics in precision UCN decays. https://arxiv.org/abs/1403.2447

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