# Recherche du boson de Higgs dans le canal $ZH \to \nu\bar nu b\bar b$ dans l'experience D0 auprès du TeVatron

Abstract : The origin of the electroweak symmetry breaking is one the pending questions at the beginning of the XXIst century. Imagined in the 1960's, the Higgs mechanism offers a theoretical solution to this problem, while predicting a new particle, the Higgs boson, undiscovered up to now.
This particle has been searched with the D0 detector at the Tevatron hadronic collider, with a center of mass energy of 1,96 TeV. The analysis channel is $ZH\to\nunub\bbb$.
For this search, an optimization of the trigger conditions specific to signals with jets plus missing transverse energy final states has been performed. Moreover, a tool was designed to measure the corresponding efficiencies.
A precise determination of the jet energies is also an essential ingredient for this analysis. A method was developed in order to correct the simulated jets for the differences observed in jet energy scale, energy resolution and reconstruction efficiency between data and simulation.
The data analysis, performed with an integrated luminosity of 2.1 fb$^{-1}$, did not reveal any excess. For a Higgs boson mass of 115 GeV, a limit has been set at 95\% C.L. on the cross section times branching fraction of $(p\bar{p}\to H(Z/W))\times(H\to b\bar{b})$, which is 7.5 times larger than the standard model value.
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https://tel.archives-ouvertes.fr/tel-00341890
Contributor : Christophe Ochando <>
Submitted on : Wednesday, November 26, 2008 - 11:46:30 AM
Last modification on : Wednesday, September 16, 2020 - 4:20:01 PM
Long-term archiving on: : Monday, June 7, 2010 - 11:25:01 PM

### Identifiers

• HAL Id : tel-00341890, version 1

### Citation

C. Ochando. Recherche du boson de Higgs dans le canal $ZH \to \nu\bar nu b\bar b$ dans l'experience D0 auprès du TeVatron. Physique des Hautes Energies - Expérience [hep-ex]. Université Paris Sud - Paris XI, 2008. Français. ⟨tel-00341890⟩

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