First Measurement of Monoenergetic Muon Neutrino Charged Current Interactions

TL;DR

This paper reports the first measurement of monoenergetic muon neutrino charged current interactions at 236 MeV, providing new insights into neutrino-nucleus interactions using weak interactions, with a significance of 3.9 sigma.

Contribution

It presents the first measurement of monoenergetic muon neutrino interactions at 236 MeV, including cross sections and energy transfer, using neutrinos as a probe of nuclear structure.

Findings

Signal significance of 3.9 sigma.

Measured muon kinetic energy and energy transfer.

First energy transfer measurement using neutrinos.

Abstract

We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest ($K^+ \rightarrow \mu^+ \nu_\mu$) at the NuMI beamline absorber. These signal $\nu_\mu$-carbon events are distinguished from primarily pion decay in flight $\nu_\mu$ and $\overline{\nu}_\mu$ backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9$\sigma$ level. The muon kinetic energy, neutrino-nucleus energy transfer ($\omega=E_\nu-E_\mu$), and total cross section for these events is extracted. This result is the first known-energy, weak-interaction-only probe of the nucleus to yield a measurement of $\omega$ using neutrinos, a quantity thus far only accessible through electron scattering.