Search for the familon via B-+/-->pi X-+/-(0), B-+/-->(KX0)-X-+/-, and B-0 ->(KSX0)-X-0 decays

Abstract

We have searched for the two-body decay of the B meson to a light pseudoscalar meson h = pi (+/-), K+/-, K-S(0) and a massless neutral feebly interacting particle X-0 such as the familon, the Nambu-Goldstone boson associated with a spontaneously broken global family symmetry. We find no significant signal by analyzing a data sample containing 9.7 X 10(6) B(B) over bar mesons collected with the CLEO detector at the Cornell Electron Storage Ring, and set 90% C.L. upper limits B(B+/- --> h(+/-)X(0)) = 4.9 X 10(-5) and B(B-0 --> (KSX0)-X-0) = 5.3 X 10(-5). These limits correspond to a lower bound of approximately 10(8) GeV on the family symmetry breaking scale with vector coupling involving the third generation of quarks.