Measurements of the Absolute Branching Fractions of B±→K±Xc¯c

Abstract

We study the two-body decays of B ± mesons to K ± and a charmonium state X c ¯ c in a sample of 210.5 fb − 1 of data from the BABAR experiment. We perform measurements of absolute branching fractions B ( B ± → K ± X c ¯ c ) using a missing mass technique, and report several new or improved results. In particular, the upper limit B ( B ± → K ± X ( 3872 ) ) < 3.2 × 10 − 4 at 90% C.L. and the inferred lower limit B ( X ( 3872 ) → J / ψ π + π − ) > 4.2 % will help in understanding the nature of the recently discovered X ( 3872 ) .