Study of B→ρπ decays at Belle

This Letter describes a study of B meson decays to the pseudoscalar-vector final state rhopi using 31.9 x 106 BB events collected with the Belle detector at KEKB. The branching fractions B(B+ --> rho(0)pi(+)) = (8.0(-2.0-0.7)(+2.3+0.7)) X 10(-6) and B(B-0 --> rho(+/-)pi(-/+)) = (20.8(-6.3-3.1)(+6.0+2.8)) x 10(-6) are obtained. In addition, a 90% confidence level upper limit of B(B-0 --> rho(0)pi(0)) < 5.3 x 10(-6) is reported. (C) 2002 Elsevier Science B.V. All rights reserved.