1993/09/20 by G. Nardulli, Nardulli, G.
Engineering · Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Superconducting Materials and Applications #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/9309291
6pp, Latex, BARI-TH/93-156
arxiv created 1993/09/20 · openalex publication_date 1993/09/20 · arxiv updated 2009/11/30 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28
We describe two recent theoretical calculations of the B → K^* γ decay. The first method is based on an effective lagrangian incorporating chiral symmetry for the light degrees of freedom and the heavy quark spin-flavor symmetries for the heavy quarks. Using these symmetries, together with the hypothesis of polar q2 dependence of the semileptonic form factors, one is able to relate B → K^* γ and D → K^* ℓ ν decays with the result R = Γ(B → K^* γ) / Γ(b → s γ) = 0.09 ± 0.03. The second method is based on 3-point function QCD sum rules and gives the result R = 0.17 ± 0.05. Both results are in reasonable agreement with recent data from the CLEO II Collaboration.