First Measurement of Monoenergetic Muon Neutrino Charged Current Interactions

Area of Science:

• Particle Physics
• Nuclear Physics
• Neutrino Physics

Background:

• Neutrino interactions are crucial for understanding nuclear physics and the Standard Model.
• Previous studies lacked a method to measure neutrino-nucleus energy transfer (ω) with known neutrino energy.
• Electron scattering is the only prior method to measure ω.

Purpose of the Study:

• To report the first measurement of monoenergetic muon neutrino charged current interactions.
• To introduce a novel method for probing nuclear responses using neutrinos with a precisely known energy.
• To measure neutrino-nucleus energy transfer (ω) using a neutrino-based interaction.

Main Methods:

• Utilized the MiniBooNE detector and the NuMI beamline.
• Isolated 236 MeV muon neutrino events from charged kaon decay at rest (K^{+}→μ^{+}ν_{μ}).
• Differentiated signal events from background neutrino sources (pion decay) using arrival time and muon energy.

Main Results:

• Observed 236 MeV monoenergetic muon neutrino events with a significance of 3.9σ.
• Successfully extracted muon kinetic energy, neutrino-nucleus energy transfer (ω), and total cross section.
• Demonstrated the capability to measure ω using a known-energy neutrino interaction.

Conclusions:

• This study presents the first measurement of monoenergetic muon neutrino charged current interactions.
• The results establish a new, weak-interaction-only probe of the nucleus using neutrinos.
• This technique opens new avenues for studying nuclear structure and neutrino interactions.