Measurement of Branching Fractions and Charge Asymmetries in B~± → ρ~± π~0 and B~± → ρ~0 π~± Decays, and Search for B~0 → ρ~0 π~0

摘要

We present measurements of branching fractions and charge asymmetries in B-meson decays to ρ~+π ~0, ρ~0π ~+, and ρ~0π ~0. The data sample comprises 89 X 10~6Υ (4S) → BB decays collected with the BABAR detector at the PEP-Ⅱ asymmetric-energy B Factory at SLAC. We find the charge-averaged branching fractions B (B~+ → ρ~+π ~0) = [10.9 ± 1.9(stat) ± 1.9(syst)] X 10~(-6) and B(B~+ → ρ~0π ~+)= (9.5 ± 1.1 ± 0.9) X 10~(-6), and we set a 90% confidence-level upper limit B(B~0 → ρ~0π ~0) < 2.9 X 10~(-6). We measure the charge asymmetries A_(CP)~(ρ~+π ~0) = 0.24 ± 0.16 ± 0.06 and A_(CP)~(ρ~0π ~+) = -0.19 ±0.11 ±0.02.