We search for resonant production of tt̅ pairs in 4.8 fb-1 integrated luminosity of pp̅ collision data at √s=1.96 TeV in the lepton+jets decay channel, where one top quark decays leptonically and the other hadronically. A matrix-element reconstruction technique is used; for each event a probability density function of the tt̅ candidate invariant mass is sampled. These probability density functions are used to construct a likelihood function, whereby the cross section for resonant tt̅ production is estimated, given a hypothetical resonance mass and width. The data indicate no evidence of resonant production of tt̅ pairs. A benchmark model of leptophobic Z′→tt̅ is excluded with mZ′<900 GeV/c2 at 95% confidence level.
A search for resonant production of ttˉ pairs in 4.8 fb−1 of integrated luminosity of ppˉ collisions at √s=1.96 TeV
PAGLIARONE, Carmine Elvezio;
2011-01-01
Abstract
We search for resonant production of tt̅ pairs in 4.8 fb-1 integrated luminosity of pp̅ collision data at √s=1.96 TeV in the lepton+jets decay channel, where one top quark decays leptonically and the other hadronically. A matrix-element reconstruction technique is used; for each event a probability density function of the tt̅ candidate invariant mass is sampled. These probability density functions are used to construct a likelihood function, whereby the cross section for resonant tt̅ production is estimated, given a hypothetical resonance mass and width. The data indicate no evidence of resonant production of tt̅ pairs. A benchmark model of leptophobic Z′→tt̅ is excluded with mZ′<900 GeV/c2 at 95% confidence level.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.