English

Towards First Detection of the Solar MSW Transition With JUNO

High Energy Physics - Phenomenology 2026-02-02 v2 High Energy Astrophysical Phenomena High Energy Physics - Experiment Nuclear Experiment Nuclear Theory

Abstract

Matter-induced neutrino flavor mixing (the Mikheyev-Smirnov-Wolfenstein, or MSW, effect) is a central prediction of the neutrino mixing framework, but it has not been conclusively observed. Direct observation of the energy-dependent MSW transition in the solar electron-neutrino survival probability would solve this, but backgrounds have been prohibitive. We show that our new technique for suppressing muon-induced spallation backgrounds will allow JUNO to measure the MSW transition at >>4σ\sigma significance in 10 years. This would strongly support upcoming multi-$1B next-generation long-baseline experiments and their goals in cementing the neutrino mixing framework.

Cite

@article{arxiv.2512.14824,
  title  = {Towards First Detection of the Solar MSW Transition With JUNO},
  author = {Obada Nairat and John F. Beacom and Kevin J. Kelly and Shirley Weishi Li},
  journal= {arXiv preprint arXiv:2512.14824},
  year   = {2026}
}

Comments

Main text is 4 pages. Comments are welcome