Search for the standard model Higgs boson in the ZH->vvbb channel in 9.5 fb-1 of ppbar collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper reports a search for the standard model Higgs boson in the ZH->vvbb channel using 9.5 fb-1 of proton-antiproton collision data, setting limits on the production cross section and measuring WZ/ZZ production.

Contribution

It introduces a search method for the Higgs boson in the vvbb final state and provides the first limits at this energy and luminosity, also measuring WZ/ZZ cross sections.

Findings

No significant excess observed over background.

Set a 95% CL limit 4.3 times the SM prediction for Higgs at 125 GeV.

Measured WZ/ZZ cross section consistent with SM within uncertainties.

Abstract

We present a search for the standard model Higgs boson in 9.5 fb-1 of ppbar collisions at sqrt(s) = 1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. The final state considered contains a pair of b jets and is characterized by an imbalance in transverse energy, as expected from ppbar->ZH->vvbb production. The search is also sensitive to the WH->lvbb channel when the charged lepton is not identified. The data are found to be in good agreement with the expected background. For a Higgs boson mass of 125 GeV, we set a limit at the 95% C.L. on the cross section sigma(ppbar->[Z/W]H), assuming standard model branching fractions, that is a factor of 4.3 times larger than the theoretical standard model value, while the expected factor is 3.9. The search is also used to measure a combined WZ and ZZ production cross section that is a factor of 0.94 +/- 0.31(stat) +/- 0.34(syst) times the standard model prediction of 4.4 pb, with an observed significance of 2.0 standard deviations.