1994/01/19 by Patrick J. O'Donnell, Q. P. Xu, Q.P. Xu · 24 citations
Physics and Astronomy · #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Quantum and Classical Electrodynamics #Quark #Quark model #Semileptonic decay #Spin (aerodynamics) #Symmetry (geometry) #Top quark #Work (physics) #Zero (linguistics) #hep-ph
paper · pdf · doi:10.1016/0370-2693(94)90095-7
published in Physics Letters B 325(1-2), 219-226 (Elsevier BV) · 13 pages, Latex, no figure, UTPT--94--02
arxiv created 1994/01/19 · openalex publication_date 1994/04/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The exclusive rare decay B \ra K^∗ γ takes place in a region of maximum recoil, q2=0, posing a problem for nonrelativistic quark models which are usually thought to be most reliable at zero recoil. The Bauer--Stech--Wirbel (BSW) model, formulated in the infinite--momentum--frame (IMF) formalism, is designed to work at q2=0. We show in this model that the ratio relating the decay B \ra K^∗ γ and the q2--spectrum of the semileptonic decay B\ra ρe ν, becomes independent of the wave function in the SU(3) flavor symmetry limit. We show that this feature is also true in relativistic quark models formulated in the IMF or light--cone formalism, if the b quark is infinitely heavy. In fact, these relativistic models, which have a different spin structure from the BSW case, reduce to the BSW model in the heavy b--quark limit. A direct measurement of the q2--spectrum of the semileptonic decay can therefore provide accurate information for the exclusive rare decay.