Testing U(1)_Lμ-Lτ model with JUNO observation on dark matter induced neutrino flux from the galactic halo

Guey-Lin Lin¹, Thi Dieu Hien Van^1*

¹Institute of Physics, National Yang Ming Chiao Tung University, Hinschu 300, Taiwan

* Presenter:Thi Dieu Hien Van, email:hieniop96.sc09@nycu.edu.tw

In this study, we discuss how JUNO’s sensitivity (A. Abusleme et al. [JUNO], JCAP 09, 001 (2023)) to the thermally averaged Dark Matter (DM) annihilation cross section, ⟨σv⟩, can constrain the parameters of U(1)_Lμ-Lτ model, which include the mass of Ζ' gauge boson and the gauge coupling g_Z' which couples Z' to μ, τ and their associated neutrinos. For DM mass below 100 MeV, the annihilation channel χχ → Z' → ν_{μ, τ}ν_{μ, τ} can take place in the galactic halo. The final-state neutrinos shall reach the Earth and be detected by large neutrino detectors such as JUNO. We first require ⟨σv⟩ in the early universe to take the value that produces the desired DM relic density, Ω_χh² = 0.12. Under this condition, one can predict the value of ⟨σv⟩ in the present-day universe, which is generally enhanced as compared to the value in the early universe. It is found that the predicted ⟨σv⟩ in the galactic halo is testable by JUNO detector. The implication of the JUNO observation is discussed.

Keywords: Dark matter, Thermal relic, Neutrinos, Ζ' coupling, JUNO