2001/03/31 by F. Larios, G. Tavares-Velasco, C.–P. Yuan +1
Computer Science · Physics and Astronomy · #Black Holes and Theoretical Physics #Computational Physics and Python Applications #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1103/physrevd.64.055004
published as Phys.Rev. D64 (2001) 055004 · Some improvementes, references updated, 3 new figures, one new appendix, abstract and conclusions unchaged. Version to appear in Physical Review D
arxiv created 2001/05/15 · openalex publication_date 2001/08/06 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We show that a general two-Higgs-doublet model with a very light CP-odd scalar (A) can be compatible with the \ensuremathρ parameter, Br(\stackrel\ensuremath→bs\ensuremathγ), Rb,Ab, (g\ensuremath-2)_\ensuremathμ of the muon, Br(\stackrel\ensuremath→\ensuremathΥA\ensuremathγ), and the direct search via the Yukawa process at CERN LEP. For its mass around 0.2 GeV, the muon (g\ensuremath-2)_\ensuremathμ and Br(\stackrel\ensuremath→\ensuremathΥA\ensuremathγ) data require tan\ensuremathβ to be about 1. Consequently, A can behave like a fermiophobic CP-odd scalar and predominantly decay into a \ensuremathγ\ensuremathγ pair, which registers in detectors of high energy collider experiments as a single photon signature when the momentum of A is large. We compute the partial decay width of \stackrel\ensuremath→ZAAA and the production rate of ff\ensuremath→ZA\stackrel\ensuremath→AZ+ ``\ensuremathγ\ensuremathγ,'' f^\ensuremath'f\ensuremath→W^\ifmmode±\else\textpm\fiA\stackrel\ensuremath→AW^\ifmmode±\else\textpm\fi+ ``\ensuremathγ\ensuremathγ,'' and ff\ensuremath→H+H^\ensuremath-\ensuremath→W+W^\ensuremath-A\stackrel\ensuremath→AW+W^\ensuremath-+ ``\ensuremathγ\ensuremathγ'' at high energy colliders such as LEP, Fermilab Tevatron, CERN LHC, and future Linear Colliders. Other production mechanisms of a light A, such as g\stackrel\ensuremath→g\stackrel\ensuremath→hA\stackrel\ensuremath→A ``\ensuremathγ\ensuremathγ,'' are also discussed.