Skip to Main content Skip to Navigation
Journal articles

Limits on scalar leptoquark interactions and consequences for GUTs

Abstract : 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 t tbar production as measured by the CDF and D0 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 to b bbar decay width. We perform a global fit of the relevant scalar couplings. This approach can explain the (g-2)_mu anomaly while tensions among the CP violating observables in the quark sector, most notably the nonstandard CP phase (and width difference) in the Bs 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 1TeV. 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.
Document type :
Journal articles
Complete list of metadatas
Contributor : Sabine Starita <>
Submitted on : Tuesday, December 13, 2011 - 4:26:43 PM
Last modification on : Wednesday, September 16, 2020 - 4:22:20 PM

Links full text





Ilja Dorsner, Jure Drobnak, Svjetlana Fajfer, Jernej F. Kamenik, Nejc Kosnik. Limits on scalar leptoquark interactions and consequences for GUTs. Journal of High Energy Physics, Springer, 2011, 11, pp.2. ⟨10.1007/JHEP11(2011)002⟩. ⟨in2p3-00651463⟩



Record views