Evidence for B+→¯¯¯¯K*0K*+

Abstract

We present measurements of the branching fraction and fraction of longitudinal polarization for the decay B + → ¯¯¯¯ K * 0 K * + with a sample of ( 467 ± 5 ) × 10 6 B ¯¯¯ B pairs collected with the BABAR detector at the PEP-II asymmetric-energy e + e − collider at the SLAC National Accelerator Laboratory. We obtain the branching fraction B ( B + → ¯¯¯¯ K * 0 K * + ) = ( 1.2 ± 0.5 ± 0.1 ) × 10 − 6 with a significance of 3.7 standard deviations including systematic uncertainties. We measure the fraction of longitudinal polarization f L = 0.75 + 0.16 − 0.26 ± 0.03 . The first error quoted is statistical and the second is systematic.