Determining the phases alpha and gamma from time-dependent CP violation in B0 decays to rho(omega) + pseudoscalar

Abstract

A method is proposed for the determination of the unitarity angle alpha through tree penguin interference. The modes needed would be of the form B0/B0-bar -> rho0 M and B0/B0-bar -> omega M where M is spin-0 uu-bar/dd-bar meson, for instance M=pi0, eta, eta',a0 or f0. An analogous method can also determine gamma using M=KS or K_L. The validity of the theoretical approximations used may be tested by over determining alpha with several modes. If two or more modes are used, the determination has a four-fold ambiguity but additional information from pure penguin decays or theoretical estimates may be used to reduce the ambiguity to alpha, alpha+pi. The method as applied to determining gamma is probably less promising.