EXPERIMENTAL ANALYSIS OF THE PROPERTIES OF THE FIVE PION EFFECT OBSERVED IN ANTI-P P INTERACTIONS NEAR 1950-MEV/C**2

Espigat, P. ; Defoix, C. ; Dobrzynski, L. ; et al.
Nucl.Phys.B 162 (1980) 41-60, 1980.
Inspire Record 157037 DOI 10.17182/hepdata.34583

The properties of the effect observed in the reaction p p → π + π − π + π − π 0 at 1949 ± 10 MeV /c 2 (τ ≅ 80 MeV /c 2 ) are studied. The ω 0 ϱ 0 , A 2 0 π + π − and π + π − π + π − π 0 (non-resonant) channels are found to be coupled with this object. The assignment I G = 1 − is established and an analysis of the √ s behaviour of the density matrix elements for the final state ω 0 ϱ 0 clearly favour J P = 2 + , 4 + … Comparisons are made with present theoretical schemes describing this mass region.

1 data table

MAJOR CONTRIBUTION TO STRUCTURE OBSERVED AT 1949 +- 10 MEV WITH WIDTH 80 +- 20 MEV.


Phi and omega Meson Production in anti-p p Annihilations at 0.7-GeV/c-0.76-GeV/c and the OZI Rule

The BOMBAY-CERN-COLLEGE DE FRANCE-MADRID collaboration Cooper-Sarkar, Amanda M. ; Ganguli, S.N. ; Malhotra, P.K. ; et al.
Nucl.Phys.B 146 (1978) 1-10, 1978.
Inspire Record 137031 DOI 10.17182/hepdata.34858

The production of the φ and ω mesons has been studied in the reactions p p → φ(ω)π + π − and p p → φ(ω) ϱ 0 at 0.70–0.76 GeV /c . The c.m. angular distribution of the φ meson in the reaction p p → φπ + π − is found to be consistent with isotropy. The corresponding distribution for ω is not. the ratio σ( p p → φπ + π − ) σ( p p → ωπ + π − ) is (10 ± 2.4) · 10 −3 , which leads to a value of (19 ± 5) · 10 −3 when corrected for the phase-space factor. Implications of this result for the OZI rule are discussed.

2 data tables

No description provided.

No description provided.


Anti-p p Annihilations Into Four and Five Pion Final States in the t (2190) Region

Handler, T. ; Jacques, P. ; Jones, M. ; et al.
Nucl.Phys.B 101 (1975) 35, 1975.
Inspire Record 99552 DOI 10.17182/hepdata.36053

New data from a 600 000 picture exposure of the BNL 31 inch hydrogen bubble chamber to a separated antiproton beam have been analyzed to try to determine if the π + π − π + π − or π + π − π + π − π 0 final states contribute any broad or narrow structure in the T(2190) region. The resonance channel fractions determined by maximum likelihood fits are all consistent with smooth behavior through the T-region and therefore there is no significant evidence that any of these resonance channels contributes to the broad bump in the total cross section. The errors on some of the fractions, however, limit the sensitivity to ∼ 0.5 mb for enhancements in these channels.

2 data tables

RESONANCE CHANNEL PERCENTAGES FROM FIT TO PI+ PI- PI+ PI- FINAL STATE.

RESONANCE CHANNEL PERCENTAGES FROM FIT TO PI+ PI- PI+ PI- PI0 FINAL STATE.