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arXiv · 2204.12152

On two-body and three-body spin correlations in leptonic $t\bar{t}Z$ production and anomalous couplings at the LHC

Rafiqul Rahaman
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Abstract

We study the anomalous $t\bar{t}Z$ couplings in the $t\bar{t}Z$ production in leptonic final state at the $13$ TeV LHC. We use the polarizations of top quarks and $Z$ boson, two-body and three-body spin correlations among the top quarks and $Z$ boson, and the cross section to probe the anomalous couplings. We estimate one parameter and simultaneous limits on the couplings of the effective vertex as well as the effective operators for a set of luminosities $150$ fb$^{-1}$, $300$ fb$^{-1}$, $1000$ fb$^{-1}$, and $3000$ fb$^{-1}$. The polarizations and the spin correlations are found to be helpful on top of the cross section to better constrain the anomalous couplings.

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Rafiqul Rahaman. 2022-04-26. On two-body and three-body spin correlations in leptonic $t\bar{t}Z$ production and anomalous couplings at the LHC. https://doi.org/10.1007/jhep02(2023)077

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