The Forward Neutrino Flux and its Secondaries at a 10 TeV Muon Collider
Abstract
Muon decays in a muon collider ring would produce TeV neutrino and antineutrino beams of electron and muon flavor. We study this flux in the forward μ+ and μ- beam directions at a 10 TeV muon collider and introduce \mint, a dedicated Monte Carlo simulation to model neutrino fluxes accounting for muon beam dynamics. We find that a benchmark detector at 5 km from the interaction point would see about 𝒪(109) neutrino interactions per year in a ∼3~tonne fiducial volume with a beam spot size of 𝒪(1)~meter. We calculate the number of secondary muons and neutrinos generated by neutrino interactions in the rock upstream of the forward detectors and find that about two secondary high-energy and highly polarized muons from the rock would cross each detector per bunch crossing. Neutrino productions of charmed mesons and taus in the rock generate a small ντ+ν̅τ secondary flux, with 𝒪(0.2) events per year in the detectors, likely too small to be observed. Wrong-sign neutrinos from similar processes, such as νe+ν̅μ in the μ- beam, are more numerous but still a fraction no larger than 𝒪(10−8) of the number of TeV neutrino interactions. Finally, we outline how the large forward neutrino exposure can be used to search for beyond-the-Standard-Model particles produced in neutrino interactions, with examples of heavy neutral leptons coupled to electron and muon flavors through mixing or electromagnetic dipole operators.
Related
- FCC-μe: High Energy, High Luminosity Muon-Electron Collider & Neutrino Factory at CERN
- Neutrino Tridents and W-boson production at the Muon Collider
- Neutrino trident process at a muon collider
- A High-Energy Neutrino Collider within a Muon Collider
- Probing a heavy neutral lepton in a radiative neutrino model at a muon collider
BibTeX
@misc{choi2026forward,
title = {{The Forward Neutrino Flux and its Secondaries at a 10 TeV Muon Collider}},
author = {Ju-Yeol Choi and Matheus Hostert and Peiran Li and Zhen Liu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2608.02718},
eprint = {2608.02718},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.02718},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The Forward Neutrino Flux and its Secondaries at a 10 TeV Muon Collider
AU - Ju-Yeol Choi
AU - Matheus Hostert
AU - Peiran Li
AU - Zhen Liu
PY - 2026
DA - 2026/09/05
PB - arXiv
DO - 10.48550/arxiv.2608.02718
UR - https://arxiv.org/abs/2608.02718
AB - Muon decays in a muon collider ring would produce TeV neutrino and antineutrino beams of electron and muon flavor. We study this flux in the forward μ^+ and μ^- beam directions at a 10 TeV muon collider and introduce \mint, a dedicated Monte Carlo simulation to model neutrino fluxes accounting for muon beam dynamics. We find that a benchmark detector at 5 km from the interaction point would see about 𝒪(10^9) neutrino interactions per year in a ∼3~tonne fiducial volume with a beam spot size of 𝒪(1)~meter. We calculate the number of secondary muons and neutrinos generated by neutrino interactions in the rock upstream of the forward detectors and find that about two secondary high-energy and highly polarized muons from the rock would cross each detector per bunch crossing. Neutrino productions of charmed mesons and taus in the rock generate a small ν_τ+ν̅_τ secondary flux, with 𝒪(0.2) events per year in the detectors, likely too small to be observed. Wrong-sign neutrinos from similar processes, such as ν_e+ν̅_μ in the μ^- beam, are more numerous but still a fraction no larger than 𝒪(10^−8) of the number of TeV neutrino interactions. Finally, we outline how the large forward neutrino exposure can be used to search for beyond-the-Standard-Model particles produced in neutrino interactions, with examples of heavy neutral leptons coupled to electron and muon flavors through mixing or electromagnetic dipole operators.
ER -