Abstract
We study the processes and in which an energetic photon is radiated from the initial state. The data are collected with the BABAR detector at SLAC. About 14 000 and 4700 events, respectively, are selected from a data sample corresponding to an integrated luminosity of . The invariant mass of the hadronic final state defines the effective center-of-mass energy. From the mass spectra, the first precise measurement of the cross section and the first measurement ever of the cross section are performed. The center-of-mass energies range from threshold to 4.35 GeV. The systematic uncertainty is typically between 10% and 13%. The contributions from , , and other intermediate states are presented. We observe the and in most of these final states and measure the corresponding branching fractions, many of them for the first time.
30 More- Received 30 October 2018
DOI:https://doi.org/10.1103/PhysRevD.98.112015
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society