Bounds on the anomalous $HZ\gamma$ vertex arising from the process $e^+e^-\to \tau^+ \tau^- \gamma$

TL;DR

This paper derives bounds on the anomalous $HZ ext{ extbackslash}gamma$ vertex using LEP data, constraining new physics effects beyond the Standard Model within a specific Higgs mass range.

Contribution

It provides the first experimental limits on the $HZ ext{ extbackslash}gamma$ coupling from $e^+e^- o au^+ au^- ext{ extbackslash}gamma$ data, improving understanding of Higgs interactions.

Findings

Bounds on the $HZ ext{ extbackslash}gamma$ coupling are of order $10^{-2}$.

Limits are set for Higgs masses between 115 and 145 GeV.

Results are two orders of magnitude above Standard Model predictions.

Abstract

We obtain limits on the anomalous coupling $HZ\gamma$ through data published by the L3 Collaboration on the process $e^+e^-\to \tau^+\tau^- \gamma$. Our analysis leads to bounds on this coupling of order $10^{-2}$, for an intermediate mass Higgs boson $115 < M_H < 145$ $GeV$, two orders of magnitude above the Standard Model prediction.