Global fit on coloured scalars including the last W-boson mass measurement

TL;DR

This paper performs a comprehensive global fit of a colour-octet scalar extension to the electroweak theory, analyzing its compatibility with current data, including the recent W-boson mass measurement, and deriving bounds on model parameters.

Contribution

It introduces a minimal flavour violation-compatible colour-octet scalar model and assesses its viability against recent experimental data using a global fit approach.

Findings

The model faces challenges fitting the new W-boson mass measurement.

Current data constrains the scalar's Yukawa couplings and mass parameters.

Limits are set on the neutron electric dipole moment contributions.

Abstract

We consider a simple extension of the electroweak theory, incorporating one $SU(2)_L$ doublet of colour-octet scalars with Yukawa couplings satisfying the principle of minimal flavour violation. Using the HEPfit package, we perform a global fit to the available data, including all relevant theoretical constraints, and extract the current bounds on the model parameters. We also calculate the contributions of the additional coloured scalars to the electric dipole moment of the neutron and set limits on its parameter space using the current experimental information. Finally, we study the effect that the last measurement of the $W$-boson mass has in our fit and show how the colour-octet scalar extension struggles to accommodate the new measurement.