Partial-wave analyses of the (3π)-system in the reaction π − p → π − π − π + p at 11.2 GeV/ c

The Bologna-Florence-Genoa-Milan-Oxford-Pavia collaboration Thompson, G. ; Antich, P. ; Boldetti, A. ; et al.
Nucl.Phys.B 101 (1975) 285-303, 1975.
Inspire Record 2860 DOI 10.17182/hepdata.36138

The results are presented of two partial-wave analyses of the (3π) − system in 30 000 events of the reaction π − p → π − π − π + p at 11.2 GeV/ c . Both techniques incorporate the assumptions of the isobar model and are (a) the University of Illinois program which fits in terms of the (3π) density matrix elements and (b) an amplitude parametrisaton including possible effects of both spin non-flip and spin flip at the baryon vertex. The results obtained with these independent programs are found to be very close.

2 data tables

NORMALIZED TO A TOTAL REACTION CROSS SECTION OF 1.17 +- 0.24 MB. ALL QUOTED CROSS SECTIONS ARE FOR INTEGRATED BREIT-WIGNERS.

A2 2+D-WAVE FOR 1.2 < M(3PI) < 1.4 GEV. THE FIRST THREE COMBINATIONS OF DENSITY MATRIX ELEMENTS ARE FOR NATURAL PARITY EXCHANGE, AND THE REMAINDER UNNATURAL.


The Exclusive Channel pi- pi- pi+ p in pi- p Interactions at 147-GeV/c.

Fong, D. ; Heller, M. ; Shapiro, A.M. ; et al.
Nuovo Cim.A 34 (1976) 659-671, 1976.
Inspire Record 112629 DOI 10.17182/hepdata.37618

The results of a study of the reaction π-p→π-π-π+p at2 147 GeV/c carried out at the Fermilab Proportional Wire 30″ Bubble Chamber Hybrid Spectrometer are reported. More than 92% of the cross-section ((670±41) μb) for this reaction is contained in those for proton and pion diffraction dissociation. The cross-sections for pion diffraction events with three-pion invariant mass in given regions are in agreement with values obtained by extrapolation of fits to data at lower incidentpion momenta. ρ0π- events make an important contribution in the A1 and A2 mass regions, and the data are consistent with contributions from f0π- in the A3 mass region. The cross-section for proton diffraction events is in agreement with a smooth extrapolation of the data at lower momentum.

1 data table

No description provided.


PRISM Plot Analysis of the Reaction pi- p --> p pi+ pi- pi- at 16-GeV/c

The Aachen-Berlin-Bonn-CERN-Cracow-Heidelberg-Warsaw collaboration Grassler, H. ; Honecker, R. ; Kirk, H.G. ; et al.
Nucl.Phys.B 113 (1976) 365-377, 1976.
Inspire Record 109661 DOI 10.17182/hepdata.35583

A prism plot analysis of the reaction π − p→p π + π − π − at 16 GeV/ c has been made and the results are compared with those obtained in a similar analysis of the reaction π + p→ p π + π + π − at the same energy. The three dominating reaction mechanisms (pion dissociation, reggeon exchange, proton diffraction dissociation) appear to be well separated, while considerable residual overlaps are present inside these classes. The prism plot method is discussed as a means for detecting hidden structures and some evidence is presented for a broad three-pion enhancement around 2 GeV decaying primarily into ϱ 0 π − .

2 data tables

No description provided.

A4(1900) IS CALLED A*(1800) BY AUTHORS. PI+ P CROSS SECTIONS PREVIOUSLY PUBLISHED IN M. DEUTSCHMANN ET AL., NP B99, 397 (1975).