First Search for Lorentz and CPT Violation in Double Beta Decay with EXO-200

L. J. Kaufman

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arXiv · 1608.05748

First Search for Lorentz and CPT Violation in Double Beta Decay with EXO-200

L. J. Kaufman

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Abstract

This proceedings contribution reports the first experimental search for Lorentz- and CPT-violating signals specifically studying the effect of the Standard-Model Extension (SME) oscillation-free momentum-independent neutrino coupling operator in the double beta decay process. The search has been performed using an exposure of 100 kg yr of $^{136}$Xe with the EXO-200 detector. No significant evidence of the spectral modification due to isotropic Lorentz violation was found. A two-sided limit of $-2.65 \times 10^{-5}$ GeV $<$ $\mathring{a}_{\mathrm{of}}^{(3)}$ $< 7.60 \times 10^{-6}$ GeV (90% C.L.) is placed on the relevant coefficient within the SME.

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L. J. Kaufman. 2016-08-19. First Search for Lorentz and CPT Violation in Double Beta Decay with EXO-200. https://arxiv.org/abs/1608.05748

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