Evidence for Two Narrow p anti-p Resonances at 2020-MeV and 2200-MeV

The CERN-College de France-Ecole Poly-Orsay collaboration Benkheiri, P. ; Boucrot, J. ; Bouquet, B. ; et al.
Phys.Lett.B 68 (1977) 483, 1977.
Inspire Record 119491 DOI 10.17182/hepdata.27541

From the study of the reaction π − p→p F p p π − using a fast proton (p F ) trigger device in the CERN Omega spectrometer, we find evidence for two narrow p p states produced mainly in association with a Δ° (1232) and a N° (1520). The statistical significance of each peak is greater than 6 standard deviations. Masses and natural widths of these resonances are respectively M = 2020 ± 3 MeV , Λ 1 = 24 ± 12 MeV and M 2 = 2204 ± 5 MeV, Λ 2 = 16 −16 +20 MeV. Our data are consistent with a small production of the narrow ∼ 1935 MeV resonance already reported. Production cross sections for these new p p resonances are given.

1 data table

ERRORS TAKE INTO ACCOUNT STATISTICAL ERRORS AND BACKGROUND SUBTRACTION UNCERTAINTY BUT NOT ACCEPTANCE CORRECTIONS UNCERTAINTY OF 15 PCT.