Light dark bosons in the JUNO-TAO neutrino detector

TL;DR

This paper evaluates the JUNO-TAO detector's potential to detect light dark bosons like dark photons, axion-like particles, and scalars, demonstrating sensitivity improvements and analyzing cross sections for these particles.

Contribution

It provides the first sensitivity estimates for dark boson detection at JUNO-TAO and derives relevant cross sections for their interactions with electrons.

Findings

Sensitivity to dark bosons can reach ~10^{-5} at 95% C.L.

Background systematic uncertainty limits sensitivity improvements.

Derived differential cross sections for all three boson types.

Abstract

This work presents a sensitivity study of a reactor liquid scintillator detector to three kinds of dark bosons with masses below 1 MeV, such as dark photons, axion-like particles and light scalar bosons. The JUNO-TAO detector with Taishan nuclear reactor is taken as a reference. With proposed 180 days data taking, the sensitivity to the dark bosons can reach $\sim10^{-5}$ 95%C.L. for the optimized signal to background ratio for the electron coupling constant $\it{g_X} $ through inverse Compton-like scattering. Similar calculations are completed for axion-like particles and scalar bosons. The background systematic uncertainty presents as the main limiting factor for the further sensitivity improvement. Several remarks are made to the controversial analysis for the NEOS experiment. Additionally the differential and the inverse differential cross sections have been derived for all three boson types and their interactions with electrons in liquid scintillator.