Muon <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>g</mml:mi><mml:mo>−</mml:mo><mml:mn>2</mml:mn></mml:mrow></mml:math> in a two-Higgs-doublet model with a type-II seesaw mechanism
Chuan-Hung Chen, Cheng-Wei Chiang, Takaaki Nomura
Abstract
We study the two-Higgs-doublet model with a type-II seesaw mechanism. In view of constraints from the Higgs data, we consider the aligned two-Higgs-doublet scheme and its effects on muon anomalous magnetic dipole moment, ${a}_{\ensuremath{\mu}}$, including both one-loop and two-loop Barr-Zee type diagrams. Thanks to a sizable trilinear scalar coupling, the Barr-Zee type diagrams mediated by the Higgs triplet fields have a dominant effect on ${a}_{\ensuremath{\mu}}$. In particular, unlike the usual two-Higgs-doublet models that require exotic Higgs bosons light in mass, the masses of the corresponding particles in the model are of $\mathcal{O}(100)\text{ }\text{ }\mathrm{GeV}$. The doubly charged Higgs boson presents a different decay pattern from the usual Higgs triplet model and thus calls for a new collider search strategy, such as multi-$\ensuremath{\tau}$ searches at the LHC.