A study of E/ι region in the ηπ oπ o decay channel with GAMS-4000 spectrometer
Abstract
A spin-parity analysis of the ηπ oπ o-system produced in the charge exchange π -p → ηπ oπ oη reaction is performed in a mass range up to 1.9 GeV. The data have been collected with the GAMS-4000 multiphoton spectrometer in 100 GeV/c secondary π- beam of SPS at CERN. Clear peaks are observed in the mass spectra corresponding to the η(1295) and ι/η(1440) mesons in the pseudoscalar sector and to the D/ƒ 1(1285) and ƒ 1(1420) mesons in the axial-vector sector. Their masses and widths are in a good agreement with the world average values. Several decay branching ratios of these mesons are measured. The η(1295) decay to ηπ oπ o is dominated by the ao(980) π o subchannel. Contrary to this, the ι/η(1440) → ao(980) πo decay is rather week, the η(π oπ o)s subchannel dominates in the iota to ηπ oπ o decay. This is an argument towards the iota assignment as an exotic meson with a strong valence gluon component.
- Publication:
-
Nuclear Physics B Proceedings Supplements
- Pub Date:
- June 1997
- DOI:
- 10.1016/S0920-5632(97)00279-X
- Bibcode:
- 1997NuPhS..56..222P