Search for the decay B0 → a±1ρ∓

Abstract

We present a search for the rare B -meson decay B 0 → a ± 1 ρ ∓ with a ± 1 → π + π − π ± . We use ( 110 ± 1.2 ) × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We obtain an upper limit of 30 × 10 − 6 ( 90 % C . L . ) for the branching fraction product B ( B 0 → a ± 1 ρ ∓ ) B ( a ± 1 → π + π − π ± ) , where we assume that the a ± 1 decays exclusively to ρ 0 π ± .