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Nucleon Decay and $n$-$bar n$ Oscillations in a Left-Right Symmetric Model with Large Extra Dimensions

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 نشر من قبل Robert Shrock
 تاريخ النشر 2020
  مجال البحث
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We study baryon-number-violating processes, including proton and bound neutron decays and $n-bar n$ oscillations, in a left-right-symmetric (LRS) model in which quarks and leptons have localized wavefunctions in extra dimensions. In this model we show that, while one can easily suppress baryon-number-violating nucleon decays well below experimental bounds, this does not suppress $n-bar n$ transitions, which may occur at levels comparable to current limits. This is qualitatively similar to what was found in an extra-dimensional model with a Standard-Model low-energy effective field theory (SMEFT). We show that experimental data imply a lower limit on the mass scale $M_{n bar n}$ characterizing the physics responsible for $n-bar n$ oscillations in the LRS model that is significantly higher than in the extra-dimensional model using a SMEFT and explain the reason for this. Our results provide further motivation for new experiments to search for $n - bar n$ oscillations.

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