Synergies of Drell-Yan, beauty, top, and Z observables in MFV-SMEFT

TL;DR

This paper demonstrates that combining diverse high-energy physics observables within the SMEFT framework, especially under MFV assumptions, enhances the ability to constrain new physics and predicts measurable flavor-changing decay rates.

Contribution

It introduces a comprehensive global fit approach combining top, flavor, and Drell-Yan data under MFV, improving constraints on SMEFT operators and predicting dineutrino branching ratios.

Findings

Synergistic combination of observables improves SMEFT constraints.

MFV significantly enhances the strength of flavor physics bounds.

Predicted dineutrino branching ratios are testable at Belle II.

Abstract

The Standard Model Effective Field Theory (SMEFT) is a powerful tool to search for new physics in a model-independent way. We explore the synergies arising from different types of observables in a combined, global SMEFT fit. Specifically, we investigate the combination of top-quark measurements, $b\to s$ flavor changing neutral current transitions, $Z\to b \bar b$ and $Z\to c \bar c$, as well as Drell-Yan data from the LHC. We also examine the impact of Minimal Flavor Violation (MFV) as a flavor pattern in the global fit. We find that the combination of high-p$_T$ with flavor physics observables provides powerful synergies that significantly improve the fit and enable more precise tests of various SMEFT operators. By incorporating different observables, we are able to remove flat directions in the parameter space and infer on the flavor structure based on the MFV parameterization. In particular, we find that MFV significantly strengthens the constraints in comparison to a flavor-specific approach. Furthermore, our analysis yields a prediction for the dineutrino branching ratios ${\cal{B}}(B \to K^{(*)} \nu \bar \nu)$ within MFV, which can be tested experimentally at Belle II.