Abstract
Using a total of of collision data with center-of-mass energies between 4.009 and 4.6 GeV and collected with the BESIII detector at BEPCII, we measure fifteen exclusive cross sections and effective form factors for the process by means of a single baryon-tag method. After performing a fit to the dressed cross section of , no significant or resonance is observed in the final states, and upper limits at the 90% confidence level on for the processes are determined. In addition, an excited baryon at is observed with a statistical significance of by including the systematic uncertainty, and the mass and width are measured to be and , which confirms the existence of the state .
- Received 14 October 2019
- Revised 5 December 2019
DOI:https://doi.org/10.1103/PhysRevLett.124.032002
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