2011/07/31 by Ilja Doršner, Ilja Dorsner, Jure Drobnak +4 · 3 citations
Computer Science · Physics and Astronomy · #Asymmetry #Computational Physics and Python Applications #Electroweak interaction #Hypercharge #Leptoquark #Neutrino Physics Research #Observable #Particle physics theoretical and experimental studies #Physics beyond the Standard Model #Quark #Scalar (mathematics) #hep-ph
paper · pdf · doi:10.1007/jhep11(2011)002
26 pages, 7 figures; version as published
openalex publication_date 2011/11/01 · arxiv created 2011/12/19 · arxiv updated 2015/03/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
A colored weak singlet scalar state with hypercharge 4/3 is one of the possible candidates for the explanation of the unexpectedly large forward-backward asymmetry in tt production as measured by the CDF and DØ experiments. We investigate the role of this state in a plethora of flavor changing neutral current processes and precision observables of down-quarks and charged leptons. Our analysis includes tree- and loop-level mediated observables in the K and B systems, the charged lepton sector, as well as the Z → bb decay width. We perform a global fit of the relevant scalar couplings. This approach can explain the (g − 2) μ anomaly while tensions among the CP violating observables in the quark sector, most notably the nonstandard CP phase (and width difference) in the B s system cannot be fully relaxed. The results are interpreted in a class of grand unified models which allow for a light colored scalar with a mass below 1 TeV. We find that the renormalizable SU(5) scenario is not compatible with our global fit, while in the SO(10) case the viability requires the presence of both the 126- and 120-dimensional representations.