Search for light sterile neutrinos with two neutrino beams at MicroBooNE
- P. Abratenko
- D. Andrade Aldana
- L. Arellano
- J. Asaadi
- A. Ashkenazi
- S. Balasubramanian
- B. Baller
- A. Barnard
- G. Barr
- D. Barrow
- J. Barrow
- V. Basque
- J. Bateman
- O. Benevides Rodrigues
- S. Berkman
- A. Bhat
- M. Bhattacharya
- M. Bishai
- A. Blake
- B. Bogart
- T. Bolton
- M. B. Brunetti
- L. Camilleri
- D. Caratelli
- F. Cavanna
- G. Cerati
- A. Chappell
- Y. Chen
- J. M. Conrad
- M. Convery
- L. Cooper-Troendle
- J. I. Crespo-Anadón
- R. Cross
- M. Del Tutto
- S. R. Dennis
- P. Detje
- R. Diurba
- Z. Djurcic
- K. Duffy
- S. Dytman
- B. Eberly
- P. Englezos
- A. Ereditato
- J. J. Evans
- C. Fang
- B. T. Fleming
- W. Foreman
- D. Franco
- A. P. Furmanski
- F. Gao
2025-12-03
The existence of three distinct neutrino flavours, ν e , ν μ and ν τ , is a central tenet of the Standard Model of particle physics 1,2 . Quantum-mechanical interference can allow a neutrino of one initial flavour to be detected sometime later as a different flavour, a process called neutrino oscillation. Several anomalous observations inconsistent with this three-flavour picture have motivated the hypothesis that an additional neutrino state exists, which does not interact directly with matter, termed as ‘sterile’ neutrino, ν s (refs. 3–9 ). This includes anomalous observations from the Liquid Scintillator Neutrino Detector (LSND) 3 experiment and Mini-Booster Neutrino Experiment (MiniBooNE) 4,5 , consistent with ν μ → ν e transitions at a distance inconsistent with the three-neutrino picture. Here we use data obtained from the MicroBooNE liquid-argon time projection chamber 10 in two accelerator neutrino beams to exclude the single light sterile neutrino interpretation of the LSND and MiniBooNE anomalies at the 95% confidence level (CL). Moreover, we rule out a notable portion of the parameter space that could explain the gallium anomaly 6–8 . This is one of the first measurements to use two accelerator neutrino beams to break a degeneracy between ν e appearance and disappearance, which would otherwise weaken the sensitivity to the sterile neutrino hypothesis. We find no evidence for either ν μ → ν e flavour transitions or ν e disappearance that would indicate non-standard flavour oscillations. Our results indicate that previous anomalous observations consistent with ν μ → ν e transitions cannot be explained by introducing a single sterile neutrino state.