2008/10/13 by Yu-Ming Wang, M. Jamil Aslam, Cai-Dian Lü +1 · 34 citations
Mathematics · Physics and Astronomy · #Asymmetry #Baryon #Black Holes and Theoretical Physics #Branching fraction #Combinatorics #Compactification (mathematics) #Dimension (graph theory) #Extra dimensions #Light cone #Mathematics #Particle physics #Particle physics theoretical and experimental studies #Physics #Physics beyond the Standard Model #Quantum Chromodynamics and Particle Interactions #Standard Model (mathematical formulation) #Universal extra dimension #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-008-0835-8
published in The European Physical Journal C 59(4), 847-860 (Springer Science+Business Media) · 22 pages, 6 figures, two references added
arxiv created 2008/10/13 · openalex publication_date 2008/12/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The exclusive weak decay of Λb → Λγ and Λb → Λl+ l- are investigated in the Applequist-Cheng-Dobrescu model, which is an extension of the standard model in presence of universal extra dimensions. Employing the transition form factors obtained in the light-cone sum rues, we analyze how the invariant mass distribution, forward-backward asymmetry and polarization asymmetry of Λ baryon of these decay modes can be used to constrain the only one additional free parameter with respect to the standard model, namely, the radius R of the extra dimension. Our results indicate that the Kaluza-Klein modes can lead to approximately 25% suppression of the branching ratio of Λb → Λγ, however, their contributions can bring about 10% enhancement to the decay rate of Λb → Λl+ l-. It is shown that the zero-position of forward-backward asymmetry of Λb → Λμ+ μ- is sensitive to the compactification parameter R in this scenario, while the measurement of polarizations of Λ baryon in the Λb decays is not suitable to provide some valuable information for the universal extra dimension model.