Electroweak dark matter model accounting for the CDF $W$-mass anomaly

TL;DR

This paper proposes electroweak multiplet models that explain the CDF W-mass anomaly and provide dark matter candidates, with numerical analysis showing success in one model but not the other.

Contribution

It introduces two new electroweak multiplet models that account for the W-mass anomaly and dark matter, with detailed parameter scans and constraints analysis.

Findings

Singlet-triplet scalar DM model explains the anomaly and dark matter constraints.

Singlet-doublet fermionic DM model does not find suitable parameters.

Models are consistent with relic density and direct detection constraints.

Abstract

Recently, the CDF collaboration reported a new measurement of the $W$ boson mass $M_W = 80.4335 \pm 0.0094$ GeV, which shows a $\sim 7\sigma$ deviation from the standard model prediction $80.3545 \pm 0.0057$ GeV obtained by the electroweak (EW) global fit. This deviation can be explained by new physics generating moderate EW oblique parameters $S$, $T$, and $U$. In this work, we use the loop corrections induced by some extra EW multiplets to explain the CDF $M_W$ anomaly. The lightest neutral particle in the multiplets can also serve as a candidate of cold dark matter (DM). We consider two such models, namely singlet-triplet scalar DM and singlet-doublet fermionic DM models, and perform numerical scans to find the parameter points accounting for the $M_W$ anomaly. The constraints from the correct DM thermal relic density and direct detection are also taken into account. We find the parameter points simultaneously interpreting the $M_W$ anomaly and satisfying the DM requirements in the former model, but do not find such parameter points in the latter model.