2005/03/14 by Francisco J. Botella, F. J. Botella, João P. Silva +1
Physics and Astronomy · #Neutrino Physics Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.71.094008
published as Phys.Rev. D71 (2005) 094008 · 16 pages, RevTex
arxiv created 2005/03/14 · openalex publication_date 2005/05/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
When studying B decays within the standard model (SM), it is customary to use the unitarity of the CKM matrix in order to write the decay amplitudes in terms of only two of the three weak phases which appear in the various diagrams. Occasionally, it is mentioned that those two weak phases can be used in order to describe any decay amplitude, even beyond the standard model. Here we point out that, when describing a generic decay amplitude, the two weak phases can be chosen completely at will, and we study the behavior of the decay amplitudes under changes in the two weak phases chosen as a basis. Of course, physical observables cannot depend on such reparametrizations. This has an impact on discussions of the SM and on attempts to parametrize new physics effects in the decay amplitudes. We illustrate these issues by looking at B\ensuremath→\ensuremathψKS and the isospin analysis in B\ensuremath→\ensuremathπ\ensuremathπ.