$W$-boson Mass Anomaly from High-Dimensional Scalar Multiplets

TL;DR

This paper explores two mechanisms involving high-dimensional scalar multiplets that could explain the recent $W$-boson mass anomaly, one at tree level and one at one-loop level, without conflicting with existing constraints.

Contribution

It introduces novel high-dimensional scalar multiplet models, including an octuplet with hypercharge 7/2, to account for the $W$-boson mass anomaly at both tree and loop levels.

Findings

Both mechanisms can explain the $W$-boson mass anomaly.

Models are consistent with current experimental constraints.

High-dimensional scalar multiplets offer viable new physics explanations.

Abstract

In light of the recently discovered $W$-boson mass anomaly by the CDF Collaboration, we discuss two distinct mechanisms that could possibly explain this anomaly through the introduction of high-dimensional $SU(2)_L$ scalar multiplets. The first mechanism is the tree-level $W$-boson mass correction induced by the vacuum expectation values of one or more $SU(2)_L$ scalar multiplets with odd dimensions of $n\geq 3$ and zero hypercharge of $Y=0$ in order to avoid the strong constraint from measurements of the $Z$-boson mass. The second mechanism is to consider the one-loop level $W$-boson mass correction from a complex multiplet. In particular, we focus on the case with an additional scalar octuplet with $Y=7/2$. As a result, we find that both mechanisms can explain the $W$-boson mass anomaly without violating any other theoretical or experimental constraints.