Double-hit signature of millicharged particles in 3D segmented neutrino detector

Dmitry Gorbunov,Igor Krasnov,Yury Kudenko,Sergey Suvorov

doi:10.1016/j.physletb.2021.136641

Abstract

We calculate the production of hypothetical millicharged particles (MCPs) of sub-GeV masses by the J-PARC proton beam in the framework of T2K and future T2HK neutrino oscillation experiments. Concentrating on the region of model parameter space, where an MCP can hit the near neutrino detector twice, we adopt this background-free signature to estimate the sensitivity of T2K and T2HK experiments to MCPs. We find that a previously inaccessible in direct searches region of charges 5×10−4-10−2e for MCP masses 0.1-0.5 GeV can be probed.

Highlights

We calculate the production of hypothetical millicharged particles (MCPs) of sub-GeV masses by the J-PARC proton beam in the framework of T2K and future T2HK neutrino oscillation experiments
Neutrino detectors are not suited for the detection of feebly interacting massive particles (FIMPs), since its interaction inside the detector closely mimics that of neutrino
For T2HK oscillation measurements with NP OT = 2.7 × 1022 protons on target to be collected for about 10 years of operation and the upgraded T2K near detector designed as described in Ref. [12], we find this signature very promising

Summary

Introduction

We calculate the production of hypothetical millicharged particles (MCPs) of sub-GeV masses by the J-PARC proton beam in the framework of T2K and future T2HK neutrino oscillation experiments. We performed simulations for Nsim = 2 × 106 protons on target (POT) which reveal the following (approximate) numbers of produced light mesons participating in the MCP phenomenology: Nπ = 6.24 × 106 , Nη = 7.94 × 105 , Nη = 2.96 × 105 , Nρ = 4.16 × 105 , Nω = 2.32 × 105 , Nφ = 1.01 × 104 .

Results

Conclusion