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arXiv · hep-ph/0512262

Improved Measurement of ttZ Couplings at the LHC

U. Baur·A. Juste·D. Rainwater·L. H. Orr
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Abstract

We consider QCD tt~Z production at the LHC with Z->\barννand all-hadronic tt~ decays, i.e. pp -> p_T(miss)bb~+4 jets, as a tool to measure ttZ couplings. This channel has a significantly larger cross section than those where the Z boson decays leptonically. However, tt~, bb~+4 jet, tt~j and tt~jj production give rise to potentially large backgrounds. We show that these processes can be suppressed to an acceptable level with suitable cuts, and find that adding the p_T(miss)bb~+4 jet channel to the final states used in previous ttZ couplings analyses will improve the sensitivity by 10-60%. We also discuss how the measurement of the ttZ couplings may constrain Little Higgs models.

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U. Baur, A. Juste, D. Rainwater, L. H. Orr. 2005-12-20. Improved Measurement of ttZ Couplings at the LHC. https://doi.org/10.1103/physrevd.73.034016

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