paper

Phenomenological study of a gauged model with a scalar leptoquark

arXiv:2305.09256 · doi:10.1103/PhysRevD.109.055038

Abstract

A gauge boson with sub-GeV mass has acquired a significant interest in phenomenology, particularly in view of the muon anomaly and coherent elastic neutrino-nucleon scattering. The latter is challenged by the nuclear recoil energy of a few tens of keV but has been observed by the COHERENT experiment. To further reconcile the observed excesses in from semileptonic charmful decays and in the boson mass, we investigate a model with a gauged symmetry and a scalar leptoquark. In contrast to the mechanism that involves kinetic mixing between the gauge bosons of and , we adopt a dynamical symmetry breaking of by incorporating an additional Higgs doublet. Through mixing with the -charged Higgs doublet, new Higgs decay channels occur at percent-level branching ratios, which could be accessible at the LHC. The -mass anomaly observed by CDF II can be potentially resolved through the enhancement in the oblique parameter . Due to the flavored gauge symmetry, the introduced scalar leptoquark exhibits a unique coupling to the -lepton, offering an explanation for the excesses observed in . Moreover, via the resonant light gauge boson decay can reach the sensitivity of Belle II at an integrated luminosity of 50 ab.

50 pages, 10 figures, typos corrected and references added

References in corpus (41)