W-boson mass in the triplet seesaw model

TL;DR

This paper explores how the type-II seesaw model, involving a scalar triplet, can explain the recent W-boson mass discrepancy reported by CDF, and predicts testable signatures at the LHC.

Contribution

It demonstrates that the type-II seesaw model can account for the W-boson mass anomaly and identifies specific scalar particles within the model that are accessible at current colliders.

Findings

Doubly-charged scalar with mass 100-200 GeV explains the W-mass discrepancy.

Preferred parameter space involves specific scalar mass splittings.

Model predictions are testable at the LHC.

Abstract

The CDF collaboration has recently published a precision measurement of the W-boson mass that differs from the Standard Model prediction by seven standard deviations. This result can be explained with additional electroweak multiplets that either break the custodial symmetry or contribute to oblique parameters at loop level. Here, we study one of the best-motivated scenarios involving new multiplets: the type-II seesaw model, which involves a scalar triplet that generates Majorana neutrino masses and can furthermore resolve the W-boson mass discrepancy. This favors a doubly-charged scalar with mass between 100 and 200 GeV as well as other scalars with a fixed mass splitting. The entire preferred parameter space is testable at the LHC.