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arXiv · 1911.11244

Electroweak Loops as a Probe of New Physics in $t\bar{t}$ Production at the LHC

Till Martini·Markus Schulze
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Abstract

We calculate the $\mathcal{O}(\alpha)$ weak corrections to top quark pair production at the LHC and include anomalous electroweak interactions from dimension-six operators. The loop calculation and renormalization are consistently done within the Standard Model Effective Field Theory. Sensitivity to the involved operators is exposed through the virtual corrections, which receive enhancement from electroweak Sudakov logarithms. We investigate the prospects of using this feature for probing New Physics at the LHC that so far has only been studied in final states with on-shell sensitivity such as $t\bar{t}+Z$ or $t \to b W$. We find that the large $t\bar{t}$ production rate and the excellent perturbative control allow compensating the loop suppression and yield remarkably strong constraints that are competitive with those from $t\bar{t}+Z$.

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Till Martini, Markus Schulze. 2019-11-25. Electroweak Loops as a Probe of New Physics in $t\bar{t}$ Production at the LHC. https://doi.org/10.1007/jhep04(2020)017

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