Can I read Towards consistent Electroweak Precision Data constraints in the SMEFT on EtoBox?

Towards consistent Electroweak Precision Data constraints in the SMEFT by Berthier, Laure; Trott, Michael is a scholarly article available to read on EtoBox.

What is Towards consistent Electroweak Precision Data constraints in the SMEFT about?

We discuss the impact of many previously neglected effects of higher dimensional operators when fitting to Electroweak Precision data (EWPD) in the Standard Model Effective Field Theory (SMEFT). We calculate the general case of $2 \rightarrow 2$ fermion scattering in the SMEFT to order $\mathcal{O}(\bar{v}_T^2/\Lambda^2)$ valid on and off the $Z$ pole, in the massless fermion limit. We demonstrate that previously neglected corrections scale as $\Gamma_Z M_Z/\bar{v}_T^2$ in the partial widths extracted from measured cross sections at LEPI, compared to the leading effect of dimension six operators in anomalous $Z$ couplings. Further, constraints on leading effects of anomalous $Z$ couplings are also modified by neglected perturbative corrections and dimension eight operators. We perform a minimal EWPD fit to illustrate the size of the error these corrections induce, when bounding leading effects. These considerations relax bounds compared to a naive leading order analysis, and show that constraints that rise above the percent level are subject to substantial theoretical uncertanties. We also argue that renormalization group running global constraints expressed through $\chi^2$ functi

Author

Berthier, Laure; Trott, Michael

Published

2015

Language

EN