Date

Study of correlations of positive and negative charged particles.

Takahashi, Y. ; Chan, C.H. ; Dong, B.L. ; et al.
Nucl.Phys.A 525 (1991) 591C-594C, 1991.
Inspire Record 328938 DOI 10.17182/hepdata.36815

Particle correlations of the central collision events of 32 S + Pb at 200 GeV/AMU have been studied by utilizing a Magnetic-Interferometric-Emulsion-Chamber (MAGIC) detector. Particle angles, momentum, and charge-signs are measured for all produced charged tracks for each event. Two-particle correlation functions, C 2 = dN (¦ p 1 − p 2 ¦= q )/ dp 1 dp 2 , for (++), (−−) and (+-) particles are examined. A source radius around 4 – 6 fm is observed for overall identical particle correlations, while unexpected short-range correlations of unlike-sign pairs are observed in the high rapidity region. An analysis of unlike-sign pairs in terms of resonance decays indicated that a large amount (40% relative to pions) of η or ω mesons (decaying into 3 π), or of scalar iso-scalar σ mesons (decaying into 2π) would be required to explain some of the data. Multi-particle charge-sign clusters are recognized; however, their “run-test” and “conjugate-test” show small deviations from statistical fluctuations.

1 data table

No description provided.


Observation of Three 2++ Resonances in the Glueball Enhanced Channel $\pi^- p \to \phi \phi n$

Etkin, A. ; Foley, K.J. ; Longacre, R.S. ; et al.
Phys.Lett.B 165 (1985) 217-221, 1985.
Inspire Record 218668 DOI 10.17182/hepdata.30309

We present data on 3652 analyzed events of the reaction π - p → φφn at 22 GeV/ c . A partial wave analysis has been performed on the φφ system. The results are well represented by three resonances all with quantum numbers I G J PC = 0 + 2 ++ . The absence of the Okubo-Zweig-Iizuka suppression observed in this reaction, the selection of only three J PC =2 ++ states ( g T , g T′ , and g T ″ ) which comprise virtually all of the cross section, and the large φφn signal over a very different φK + K - n background are all well explained if these states are produced by 1–3 glueballs (i.e. multigluon resonances).

1 data table

Slope indicates pion exchange process.