Search for Lorentz-invariance violation with the first KATRIN data
M. Aker, D. Batzler, A. Beglarian, J. Behrens, A. I. Berlëv, U. Besserer, B. Bieringer, F. Block, S. Bobien, B. Bornschein, L. Bornschein, Matthias Böttcher, T. Brunst, T. S. Caldwell, R. M. D. Carney, S. Chilingaryan, W. Choi, K. Debowski, M. Descher, D. Díaz Barrero, P. J. Doe, O. Dragoun, G. Drexlin, F. Edzards, K. Eitel, E. Ellinger, R. Engel, S. Enomoto, A. Felden, J. A. Formaggio, F. M. Fränkle, G. B. Franklin, F. Friedel, A. Fulst, K. Gauda, A. S. Gavin, W. Gil, F. Glück, Robin Größle, R. Gumbsheimer, V. Hannen, N. Haußmann, K. Helbing, S. Hickford, R. Hiller, D. Hillesheimer, D. Hinz, T. Höhn, T. Houdy, A. Huber, A. Jansen, C. Karl, J. Kellerer, M. Kleifges, M. Klein, C. Köhler, L. Köllenberger, A. Kopmann, M. Korzeczek, A. Kovalík, B. Krasch, H. Krause, L. La Cascio, T. Lasserre, T. L. Le, O. Lebeda, B. Lehnert, A. Lokhov, M. Machatschek, E. Malcherek, M. Mark, A. Marsteller, E. L. Martín, C. Melzer, S. Mertens, J. Mostafa, K. Müller, H. Neumann, S. Niemes, P. Oelpmann, D. S. Parno, A. W. P. Poon, J. Poyato, F. Priester, Jan Ráliš, S. Ramachandran, R. G. H. Robertson, Werner Rodejohann, C. Rodenbeck, M. Röllig, C. Röttele, M. Ryšavý, R. Sack, Alejandro Sáenz, R. Salomon, P. Schäfer, L. Schimpf, M. Schlösser, K. Schlösser, L. Schlüter
Abstract
Some extensions of the Standard Model of particle physics allow for Lorentz invariance and charge-parity-time invariance violations. In the neutrino sector strong constraints have been set by neutrino-oscillation and time-of-flight experiments. However, some Lorentz-invariance-violating parameters are not accessible via these probes. In this work, we focus on the parameters $({a}_{\mathrm{of}}^{(3)}{)}_{00}$, $({a}_{\mathrm{of}}^{(3)}{)}_{10}$, and $({a}_{\mathrm{of}}^{(3)}{)}_{11}$ which would manifest themselves in a nonisotropic $\ensuremath{\beta}$-decaying source as a sidereal oscillation and an overall shift of the spectral endpoint. Based on the data of the first scientific run of the KATRIN experiment, we set the first 90% confidence-level limit on $|({a}_{\mathrm{of}}^{(3)}{)}_{11}|$ of $<0.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\text{ }\text{ }\mathrm{GeV}$ to $3.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\text{ }\text{ }\mathrm{GeV}$, depending on the phase. Moreover, we derive new constraints on $({a}_{\mathrm{of}}^{(3)}{)}_{00}$ and $({a}_{\mathrm{of}}^{(3)}{)}_{10}$.