Muon Beam for Neutrino CP Violation: connecting energy and neutrino frontiers

• DOI: 10.48550/arxiv.2301.02493
• Publication Date: 2023-01-01
• Authors: Ruzi, Alim; Yang, Tianyi; Fu, Dawei; Qian, Sitian; Gao, Leyun; Li, Qiang
• Keywords: Accelerator Physics (physics.acc-ph); FOS: Physical sciences; Popular Physics (physics.pop-ph); Physics - Popular Physics; 7. Clean energy; High Energy Physics - Experiment; High Energy Physics - Phenomenology; 03 medical and health sciences; High Energy Physics - Experiment (hep-ex); 0302 clinical medicine; High Energy Physics - Phenomenology (hep-ph); Physics - Accelerator Physics

We propose here a proposal to connect neutrino and energy frontiers, by exploiting collimated muon beams for neutrino oscillations, which generate symmetric neutrino and antineutrino sources: $μ^+\rightarrow e^+\,\barν_μ\, ν_{e}$ and $μ^-\rightarrow e^-\, ν_μ \,\barν_{e}$. Interfacing with long baseline neutrino detectors such as DUNE and T2K, this experiment can be applicable to measure tau neutrino properties, and also to probe neutrino CP phase, by measuring muon electron (anti-)neutrino mixing or tau (anti-)neutrino appearance, and differences between neutrino and antineutrino rates. There are several significant benefits leading to large neutrino flux and high sensitivity on CP phase, including 1) collimated and manipulable muon beams, which lead to a larger acceptance of neutrino sources in the far detector side; 2) symmetric $μ^+$ and $μ^-$ beams, and thus symmetric neutrino and antineutrino sources, which make this proposal ideally useful for measuring neutrino CP violation. More importantly, $\barν_{e,μ}\rightarrow\barν_τ$ and $ν_{e,μ}\rightarrow ν_τ$, and, $\barν_{e}\rightarrow\barν_μ$ and $ν_{e}\rightarrow ν_μ$ oscillation signals can be collected simultaneously, with no needs for separate specific runs for neutrinos or antineutrinos. Based on a simulation of neutrino oscillation experiment, we estimate $10^4$ tau (anti-) neutrinos can be collected within 5 years which makes this proposal suitable for a brighter tau neutrino factory. Moreover, more than 7 standard deviations of sensitivity can be reached for $\dcp = |π/2|$, within only five ears of data taking, by combining tau and muon (anti-) neutrino appearances. With the development of a more intensive muon beam targeting future muon collider, the neutrino potential of the current proposal will surely be further improved.<br/>Additional fixes included. In this new version, we have now strengthened our results by carrying out a solid physics simulation with the help of GLoBES, a sophisticated software package for the simulation of long baseline neutrino oscillation experiments. The results are compared with previous qualitative estimations, and are found to be in reasonable agreement<br/>