Hydrogen portal to exotic radioactivity

TL;DR

This paper proposes that hydrogen atoms in certain dark sector models can decay and produce detectable signals, potentially explaining the XENON1T electron recoil excess through new physics portals.

Contribution

It introduces a novel dark sector model where hydrogen decay acts as a portal to new physics, providing a possible explanation for experimental anomalies.

Findings

Hydrogen decay fluxes can produce detectable signals at Earth and Sun.

Models can explain XENON1T excess without conflicting with existing decay limits.

Detection channels include decay and scattering signatures.

Abstract

We show that in a special class of dark sector models, the hydrogen atom can serve as a portal to new physics, through its decay occurring in abundant populations in the Sun and on Earth. The large fluxes of hydrogen decay daughter states can be detected via their decay or scattering. By constructing two models for either detection channel, we show that the recently reported excess in electron recoils at XENON1T could be explained by such signals in large regions of parameter space unconstrained by proton and hydrogen decay limits.