Flavour independent search for Higgs bosons decaying into hadronic final states in e+e- collisions

TL;DR

This paper reports a flavor-independent search for Higgs bosons decaying into hadronic states in e+e- collisions, setting a lower mass limit of 104 GeV/c2 at 95% confidence level.

Contribution

It introduces a broad, flavor-independent search method for hadronic Higgs decays in e+e- collisions, extending previous analyses and setting new mass limits.

Findings

No significant excess observed over background.

Set a lower Higgs mass limit of 104 GeV/c2.

Combined results from multiple energy datasets.

Abstract

A search for the Higgsstrahlung process e+e- -> hZ is described, where the neutral Higgs boson h is assumed to decay into hadronic final states. In order to be sensitive to a broad range of models, the search is performed independent of the flavour content of the Higgs boson decay. The analysis is based on e+e- collision data collected by the OPAL detector at energies between 192 GeV and 209 GeV. The search does not reveal any significant excess over the Standard Model background prediction. Results are combined with previous searches at energies around 91 GeV and at 189 GeV. A limit is set on the product of the cross-section and the hadronic branching ration of the Higgs boson, as a function of the Higgs boson mass. Assuming the hZ coupling predicted by the Standard Model, and a Higgs boson decaying only into hadronic final states, a lower bound of 104 GeV/c2 is set on the mass at the 95% confidence level.