9 research outputs found
Measurement of the cross section for and observation of an excited baryon
Using a total of 11.0 fb of collision data with
center-of-mass energies between 4.009 GeV 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 1820 MeV/ is
observed with a statistical significance of 6.2 6.5 by including
the systematic uncertainty, and the mass and width are measured to be ~MeV/ and ~MeV, which confirms the existence of the state
.Comment: 8 pages, 4 figures, 1 Supplemental Material with 2 pages, consistent
with paper published in Phys. Rev. Lett. 124, 032002 (2020