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Higgs to bb in ATLAS

A search for the \bb\ decay of the Standard Model Higgs boson is performed with the ATLAS experiment using the full dataset recorded at the LHC in Run 1. The integrated luminosities used from $pp$ collisions at $\sqrt{s}=7$ and 8~TeV are 4.7 and 20.3~\ifb, respectively. The processes considered are...

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Detalles Bibliográficos
Autor principal: Lee, J S H
Lenguaje:eng
Publicado: 2013
Materias:
Acceso en línea:http://cds.cern.ch/record/1571035
Descripción
Sumario:A search for the \bb\ decay of the Standard Model Higgs boson is performed with the ATLAS experiment using the full dataset recorded at the LHC in Run 1. The integrated luminosities used from $pp$ collisions at $\sqrt{s}=7$ and 8~TeV are 4.7 and 20.3~\ifb, respectively. The processes considered are associated \wzh\ production, with \wln, \zll\ ($\ell=e,\mu$), and \znn. No significant excess is observed above the Standard Model (SM) backgrounds. For \mh=125 GeV, a 95\% CL upper limit of 1.4 times the SM expectation is set on the cross section times branching ratio for $pp\to (W/Z)(H\to\bb)$. The corresponding limit expected in the absence of signal is 1.3. The ratio of the measured signal strength to the SM expectation is found to be $\mu = 0.2 \pm 0.5 \mathrm{(stat.)} \pm 0.4 \mathrm{(syst.)}$. %$\mu = 0.17^{+0.67}_{-0.63}$. The analysis procedure is validated by a measurement of the yield of $(W/Z)Z$ production, with $Z\to\bb$, from which the ratio of the observed signal strength to the SM expectation is found to be $\mu_{VZ} = 0.9 \pm 0.2$. % preivously 1.42 vs 1.28