1999/09/13 by Howard E. Haber, Heather E. Logan · 1 citation
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.62.015011
published as Phys.Rev. D62 (2000) 015011 · 54 pages, 11 figures
arxiv created 1999/09/13 · openalex publication_date 2000/06/09 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We explore the radiative corrections to the process \stackrel\ensuremath→Zbb in models with extended Higgs sectors. The observables Rb\ensuremath≡\ensuremathΓ(\stackrel\ensuremath→Zbb)/\ensuremathΓ(\stackrel\ensuremath→Zhadrons) and the Zbb coupling asymmetry, Ab\ensuremath≡(gL2\ensuremath-gR2)/(gL2+gR2), are sensitive to these corrections. We present general formulas for the one-loop corrections to Rb and Ab in an arbitrary extended Higgs sector, and derive explicit results for a number of specific models. We find that in models containing only doublets, singlets, or larger multiplets constrained by a custodial SU(2)c symmetry, so that MW=MZcos\ensuremathθW at tree level, the one-loop corrections due to virtual charged Higgs bosons always worsen agreement with experiment. The Rb measurement can be used to set lower bounds on the charged Higgs boson masses. Constraints on models due to the one-loop contributions of neutral Higgs bosons are also examined.