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arXiv · 1109.2542

Beyond the Standard Model with Precision Nucleon Matrix Elements on the Lattice

Huey-Wen Lin
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Abstract

Precision measurements of nucleons provide constraints on the Standard Model and can discern the signatures predicted for particles beyond the Standard Model (BSM). Knowing the Standard Model inputs to nucleon matrix elements will be necessary to constrain the couplings of dark matter candidates such as the neutralino, to relate the neutron electric dipole moment to the CP-violating theta parameter, or to search for new TeV-scale particles though non-$V-A$ interactions in neutron beta decay. However, these matrix elements derive from the properties of quantum chromodynamics (QCD) at low energies, where perturbative treatments fail. Using lattice gauge theory, we can nonperturbatively calculate the QCD path integral on a supercomputer. In this proceeding, I will discuss a few representative areas in which lattice QCD (LQCD) can contribute to the search for BSM physics, emphasizing suppressed operators in neutron decay, and outline prospects for future development.

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BibTeXRIS

Huey-Wen Lin. 2011-09-12. Beyond the Standard Model with Precision Nucleon Matrix Elements on the Lattice. https://doi.org/10.1063/1.3700610

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