Explanation of the Beryllium Anomaly in a $U(1{)}^{\prime }$-Extended 2-Higgs Doublet Model

Abstract

We consider an extension of the Standard Model with an extra gauged $U(1{)}^{\prime }$ symmetry in presence of a 2-Higgs Doublet Model structure of the scalar sector. We show that this scenario is able to explain the anomaly observed by the Atomki collaboration in the decay of an excited state of Beryllium via a light spin-1 $Z^{\prime }$ with a mass of 17 MeV.

Comments: Prepared for proceedings of EPS-HEP 2017, European Physical Society conference on High Energy Physics, 5-12 July 2017, Venice, Italy