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arXiv · 2407.10948

The infamous 95 GeV $\rm b \bar b$ excess at LEP: Two b or not two b?

Abstract

A small deviation observed around 95 GeV in the diphoton invariant mass distribution in the LHC Run 2 data has been subject to considerable attention in the past couple of years. The interpretation of this excess as the manifestation of an additional scalar particle at this mass is often claimed to be supported by a previously observed, even smaller, excess in the b\=b invariant mass distribution in LEP data. This short note aims at confronting this claim to factual experimental observations, through a careful scrutiny of the detailed LEP public notes written at the time on the topic. It is found that the LEP data strongly disfavour the production of a new 95 GeV scalar particle, as well as any other new physics interpretation in the 95-100 GeV mass range.

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Patrick Janot. 2024-07-15. The infamous 95 GeV $\rm b \bar b$ excess at LEP: Two b or not two b?. https://arxiv.org/abs/2407.10948

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