First observation of the charmless decay B+ -> K+π0π0 and study of the Dalitz plot structure

Abstract

Results for the first measurement of the inclusive branching and CP asymmetry of the charmless 3-body decay B+ -> K+π0π0 are presented. The analysis uses a data sample with an integrated luminosity of 429.0 fb−1, recorded by the BABAR detector at the PEP-II asymmetric B Factory. This sample corresponds to 470.9 ± 2.8 million BB pairs. Measurements of the branching fractions (B) and CP asymmetries (ACP) of some of the intermediate resonances in the K+π0π0 Dalitz plot are also presented. The results are summarised here: # B (B+ -> K+π0π0) = (16.2 ± 1.2 ± 1.4) × 10−6 # B (B+ -> K*(892)+π0;K*0(892) -> K+π0) = (2.72 ± 0.50 ± 0.34) × 10−6 # B (B+ -> f0(980)K+; f0(980) -> π0π0) = (2.77 ± 0.56 ± 0.43) × 10−6 # B (B+ -> Xc0K+; Xc0 -> π0π0) = (0.51 ± 0.22 ± 0.09) # ACP (B+ -> K+π0π0) = (−6 ± 6 ± 4)% # ACP (B+ -> K*(892)+π0) = (−4 ± 26 ± 4)% # ACP (B+ -> f0(980)K+) = (17 ± 18 ± 4)% # ACP (B+ -> Xc0K+) = (−89 ± 37 ± 4)