Date

MEASUREMENT OF J / psi PRODUCTION IN 280-GeV/c mu+ IRON INTERACTIONS

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 89 (1980) 267-270, 1980.
Inspire Record 143938 DOI 10.17182/hepdata.27264

Virtual photoproduction of J/ ψ mesons has been measured for 280 GeV muon iron interactions in an iron/scintillator calorimeter target. The J/ψ's were identified by their decay into muon pairs. 315 events were observed, about half of which were elastic. The t , Q 2 and v distributions of these elastic events are presented. The v dependence is measured between 40 and 180 Mev and compared with lower energy photoproduction results. The Q 2 dependence is compared with the predictions of the vector dominance model.

4 data tables

TPRIME DISTRIBUTION OF ELASTIC J/PSI EVENTS FOR ALL Q2 AND NU WITH 280 GEV MUON BEAM.

NORMALIZED Q**2 DISTRIBUTION OF ELASTIC J/PSI EVENTS FOR ALL NU AND T WITH 280 GEV MUON BEAM.

EXTRAPOLATION OF Q**2 AND T DEPENDENCE TO CALCULATE D(SIG)/DT AT Q**2=0 AND T=0 FOR ELASTIC J/PSI PHOTOPRODUCTION PER NUCLEON.

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A2 Meson Production at 63-{GeV} and 94-{GeV} in the Reaction $\pi^- p \to \pi^- \pi^- \pi^+ p$

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Phys.Lett.B 89 (1980) 276-280, 1980.
Inspire Record 143255 DOI 10.17182/hepdata.27274

The A 2 meson is studied in the decay mode ϱ 0 π − using partial wave analyses of 600 000 events from the reaction π − p→ π − π − π + p at 63 and 94 GeV incident momentum. Common production mechanisms are indicated for this resonance and diffractive 1 + and 2 − components.

1 data table

No description provided.


Elastic and total $\pi^{+}\pi^{-}$ cross-sections from a high statistics measurement of the reaction $\pi^{-}p \to \pi^{+}\pi^{-}n$ at 63 GeV/c

Weilhammer, P. ; Berglund, A. ; Chabaud, V. ; et al.
2 (1979) 628-635, 1979.
Inspire Record 148986 DOI 10.17182/hepdata.75420

A sample of about 230000 events of the reaction pi /sup -/p to pi /sup +/ pi /sup -/n, measured with a magnetic forward spectrometer set up in an unseparated pi /sup -/ beam with a momentum of 63 GeV/c at the SPS has been analysed in terms of one pion exchange. The elastic pi /sup +/ pi /sup -/ cross section has been determined using an extrapolation to the pion pole in the mass range up to m( pi /sup +/ pi /sup -/)=4 GeV. The total pi /sup +/ pi /sup -/ cross section is obtained via the optical theorem. (7 refs).

5 data tables

INTEGRATED 2- S-WAVE INTENSITY FOR 1500 TO 1800 MEV, INCLUDING SIGNIFICANT BACKGROUND.

No description provided.

No description provided.

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Analysis of the omega pi- System Produced in the Reaction pi- p --> pi- pi- pi+ pi0 p at 11.2-GeV/c

Gessaroli, R. ; Quareni-Vignudelli, A. ; Berti, S. ; et al.
Nucl.Phys.B 126 (1977) 382-396, 1977.
Inspire Record 119128 DOI 10.17182/hepdata.41905

The ωπ − mass spectrum, in the reaction π −p → ωπ − pat 11.2 GeV/ c , shows the production of the B − meson with a cross section of 27 ± 5 μb as well as a clear enhancement around 1670 MeV. In the differential cross section for B − production, there is a strong forward peak and a change of slope at t ' t 0.2 GeV 2 .

3 data tables

CORRECTED FOR BACKGROUND AND OMEGA TAILS.

No description provided.

ABS(D-WAVE/S-WAVE) = 0.4 +- 0.1 FOR B DECAY.


Study of A2- --> eta pi- in the Reaction pi- p --> pi- pi- pi+ pi0 p at 11.2-GeV/c

The Bologna-Florence-Genoa-Milan-Oxford-Pavia collaboration Forino, A. ; Gessaroli, R. ; Cartacci, A.M. ; et al.
Nuovo Cim.A 35 (1976) 465, 1976.
Inspire Record 109786 DOI 10.17182/hepdata.37635

The analysis of A2−→ηπ− at 11.2 GeV/c confirms that A2− is essentially produced by natural-parity exchange. In the differential cross-section as a function oft′ there is evidence of the dip at smallt′ values. The branching ratio (A2→ηπ)/(A2→ϱπ) is 0.18±0.05.

3 data tables

No description provided.

NUMERICAL VALUES SUPPLIED BY G. THOMPSON. 100 EVENTS IN A2 REGION DEFINED BY 1.18 < M(ETA PI-) < 1.44 GEV.

ROUGH BACKGROUND SUBTRACTION TO REMOVE NON-TRUE ETA EVENTS. FIRST THREE DENSITY MATRIX COMBINATIONS ARE NATURAL-PARITY EXCHANGE, THE REMAINDER BEING UNNATURAL-PARITY EXCHANGE.