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arXiv · 2004.07615

Signs of new physics in top quark pair production associated with a neutrino pair at the LHC

Daruosh Haji Raissi·Javad Ebadi·Mojtaba Mohammadi Najafabadi
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Abstract

In this paper, we examine the interactions of the top quarks with the $Z$ boson using the top quark pair production associated with neutrino pair ($t\bar{t}\nu_{l}\bar{\nu_{l}}$) at the LHC. In particular, potential constraints on the anomalous electroweak top-quark interactions are determined by considering two opposite-sign charged leptons, missing energy, and two b-tagged jets in the final state. The analysis is performed for a High Luminosity scenario of the LHC with an integrated luminosity of 3 ab$^{-1}$ of proton-proton collisions at a center-of-mass energy of 14 TeV. The $95\%$ confidence intervals are computed on the anomalous couplings considering a realistic detector simulation of an upgraded CMS detector including an average of 200 proton-proton interactions per bunch crossing. We find that the $t\bar{t}\nu_{l}\bar{\nu_{l}}$ channel can provide stringent bounds on the relevant Wilson coefficients and has the potential to serve as an additional handle beside the $t\bar{t}Z(Z\rightarrow l^{+}l^{-})$ and other channels to search for new physics.

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Daruosh Haji Raissi, Javad Ebadi, Mojtaba Mohammadi Najafabadi. 2020-04-16. Signs of new physics in top quark pair production associated with a neutrino pair at the LHC. https://doi.org/10.1103/physrevd.101.095002

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