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arXiv · 2109.09978

Bounds on the absorptive parts of the chromomagnetic and chromoelectric dipole moments of the top quark from LHC data

A. I. Hernández-Juárez·A. Moyotl·G. Tavares-Velasco
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Abstract

Bounds on the absorptive (imaginary) parts of the top quark chromomagnetic $\hat{\mu}_t$ and chromoelectric $\hat{d}_t$ dipole moments are obtained by reinterpreting the most recent LHC data in top quark pair production. It is found that both limits are of the order of $10^{-1}-10^{-2}$, which are consistent with the standard model prediction of ${\rm Im}\big[\hat{\mu}_t\big]$. The effects of the absorptive parts of the top quark dipole moments are also studied via some kinematic distributions of $\bar{t}t$ production, though no significant deviation from the standard model leading order contribution is observed. Our bounds can be useful to constrain the parameter space of standard model extensions.

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A. I. Hernández-Juárez, A. Moyotl, G. Tavares-Velasco. 2021-09-21. Bounds on the absorptive parts of the chromomagnetic and chromoelectric dipole moments of the top quark from LHC data. https://doi.org/10.1140/epjp%2Fs13360-022-03113-8

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