Explaining the 96 GeV Di-photon Anomaly in a Generic 2HDM Type-III

TL;DR

This paper proposes that a generic 2HDM Type-III with specific Yukawa textures can explain the 96 GeV di-photon excess and related anomalies, fitting current experimental data within 1σ.

Contribution

It demonstrates that a 2HDM Type-III with lepton flavor violation can simultaneously explain the 96 GeV di-photon and b-bbar anomalies, consistent with existing bounds.

Findings

Solutions with m_H=125 GeV and m_h=96 GeV are viable.

The model can explain the anomalies at 1σ level.

Bounds from Higgs data constrain the parameter space.

Abstract

Motivated by results recently reported by the CMS Collaboration about an excess in the di-photon spectrum at about 96 GeV, especially when combined with another long-standing anomaly at the same value in the $b\bar b$ invariant mass spectrum in four-jet events collected at LEP, we show that a possible explanation to both phenomena can be found at 1$\sigma$ level in a generic 2-Higgs Doublet Model (2HDM) of Type-III in presence of a specific Yukawa texture, wherein Lepton Flavour Violating (LFV) (neutral) currents are induced at tree level. Bounds from Higgs data play a major role in limiting the parameter space of this scenario, yet we find solutions with $m_H = 125$ GeV and $m_h = 96$ GeV consistent with current theoretical and experimental bounds.