Search for Lorentz and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>C</mml:mi><mml:mi>P</mml:mi><mml:mi>T</mml:mi></mml:math> violation using sidereal time dependence of neutrino flavor transitions over a short baseline

Abstract

A class of extensions of the Standard Model allows Lorentz and CPT\nviolations, which can be identified by the observation of sidereal modulations\nin the neutrino interaction rate. A search for such modulations was performed\nusing the T2K on-axis near detector. Two complementary methods were used in\nthis study, both of which resulted in no evidence of a signal. Limits on\nassociated Lorentz and CPT violating terms from the Standard Model Extension\nhave been derived taking into account their correlations in this model for the\nfirst time. These results imply such symmetry violations are suppressed by a\nfactor of more than $10^{20}$ at the GeV scale.\n