First Measurement of the B
Phys Rev Lett
; 130(18): 181804, 2023 May 05.
Article
in En
| MEDLINE
| ID: mdl-37204904
ABSTRACT
We study B^{+}âπ^{+}π^{0}π^{0} using 711 fb^{-1} of data collected at the Ï(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We measure an inclusive branching fraction of (19.0±1.5±1.4)×10^{-6} and an inclusive CP asymmetry of (9.2±6.8±0.7)%, where the first uncertainties are statistical and the second are systematic, and a B^{+}âρ(770)^{+}π^{0} branching fraction of (11.2±1.1±0.9_{-1.6}^{+0.8})×10^{-6}, where the third uncertainty is due to possible interference with B^{+}âρ(1450)^{+}π^{0}. We present the first observation of a structure around 1 GeV/c^{2} in the π^{0}π^{0} mass spectrum, with a significance of 6.4σ, and measure a branching fraction to be (6.9±0.9±0.6)×10^{-6}. We also report a measurement of local CP asymmetry in this structure.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Phys Rev Lett
Year:
2023
Type:
Article