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Bubble Chamber Study of Photoproduction by 2.8-GeV and 4.7-GeV Polarized Photons. 1. Cross-Section Determinations and Production of rho0 and Delta++ in the Reaction gamma p --> p pi+ pi-

Ballam, Joseph ; Chadwick, G.B. ; Gearhart, R. ; et al.

Phys.Rev.D 5 (1972) 545, 1972.

Inspire Record 67165 DOI 10.17182/hepdata.3635

Photoproduction is studied at 2.8 and 4.7 GeV using a linearly polarized monoenergetic photon beam in a hydrogen bubble chamber. We discuss the experimental procedure, the determination of channel cross sections, and the analysis of the channel γp→pπ+π−. A model-independent analysis of the ρ0-decay angular distribution allows us to measure nine independent density-matrix elements. From these we find that the reaction γp→pρ0 proceeds almost completely through natural parity exchange for squared momentum transfers |t|<1 GeV2 and that the ρ production mechanism is consistent with s-channel c.m. helicity conservation for |t|<0.4 GeV2. A cross section for the production of π+π− pairs in the s-channel c.m. helicity-conserving p-wave state is determined. The ρ mass shape is studied as a function of momentum transfer and is found to be inconsistent with a t-independent Ross-Stodolsky factor. Using a t-dependent parametrization of the ρ0 mass shape we derive a phenomenological ρ0 cross section. We compare our phenomenological ρ0 cross section with other experiments and find good agreement for 0.05<|t|<1 GeV2. We discuss the discrepancies in the various determinations of the forward differential cross section. We study models for ρ0 photoproduction and find that the Söding model best describes the data. Using the Söding model we determine a ρ0 cross section. We determine cross sections and nine density-matrix elements for γp→Δ++π−. The parity asymmetry for Δ++ production is incompatible with simple one-pion exchange. We compare Δ++ production with models.

20 data tables match query

Table 1

FROM QUOTED TOPOLOGICAL CROSS SECTIONS. 1.44 GEV CROSS SECTION PUBLISHED PREVIOUSLY.

Table 2

No description provided.

Table 3

NO TMIN CORRECTION HAS BEEN MADE.

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Study of Inclusive Production of Boson Resonances in $\bar{p} p$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Starchenko, E.A. ; Chekulaev, S.V. ; Galyaev, N.A. ; et al.

Z.Phys.C 16 (1983) 181, 1983.

Inspire Record 168177 DOI 10.17182/hepdata.22268

The inclusive production ofK*±(890), ρρ(770), ω0(780) andf0(1,270) mesons is studied in$\bar pp$ experiment at 32GeV/c in the MIRABELLE bubble chamber by the analysis of (K0π±) and (π+π−) invariant mass distributions. The inclusive cross sections are σ(K*±)=2.45±0.30 mb, σ(ρ0)=8.8 ±0.9 mb, σ(ω+)≃6.2 mb, and σ(f0)=2.2±0.7 mb. The C.M. longitudinal distribution of theK*±(890) is slightly shifted to the primary particles fragmentation regions; the ρ0 is produced more centrally. The studied mesons alone are responsible for 40% of final state poins. The production features of various resonances are compared with quark models predictions.

13 data tables match query

Table 1

No description provided.

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No description provided.

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Strangeness Suppression and Inclusive $\phi$ and $K^*$0 Production in $K^+ P$ Interactions at 250-{GeV}/c

The EHS - NA22 collaboration Adamus, M. ; Agababyan, N.M. ; Ajinenko, I.V. ; et al.

Phys.Lett.B 198 (1987) 427-432, 1987.

Inspire Record 254217 DOI 10.17182/hepdata.30075

We present inclusive ¶ and K *0 (892) cross sections and Feynman x -spectra in K + p collisions at 250 GeV/ c . In the K + fragmentation region, x > 0.2, the ratio of ¶ to K *0 (892) is used to estimate the strangeness suppression factor λ , with the result γ =0.17 ± 0.02 (stat ± 0.01 (syst). We see no evidence for an energy dependence of λ in the CM energy range 7.8 ≤ s ≤21.7 GeV.

4 data tables match query

Table 1

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

Table 2

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

Table 3

RESULTS AT 32 AND 70 GEV INCLUDED FOR COMPARISON.

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Decay distributions in the reaction k+ p ---> k*0(1420) delta++ at 5 gev/c and quark model predictions

Eskreys, A. ; Malecki, P. ; Zalewski, K. ; et al.

Nucl.Phys.B 29 (1971) 587-600, 1971.

Inspire Record 68631 DOI 10.17182/hepdata.33559

Joint decay distributions have been studied in the reaction K + p → K ∗o (1420)Δ ++ at 5.0 GeV/ c in the transversity spin reference frame. Two alternative spin-parity assignments 2 + and 3 − for the K ∗ resonance have been considered and a comparison with the quark-model predictions has been made. The predictions of the quark model are equally well satisfied by the experimental results for both the 2 + and 3 − spin-parity assignments.

1 data table match query

Table 1

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Bubble Chamber Study of Photoproduction by 2.8-GeV and 4.7-GeV Polarized Photons. 1. Cross-Section Determinations and Production of rho0 and Delta++ in the Reaction gamma p --> p pi+ pi-

Study of Inclusive Production of Boson Resonances in $\bar{p} p$ Interactions at 32-{GeV}/$c$

Strangeness Suppression and Inclusive $\phi$ and $K^*$0 Production in $K^+ P$ Interactions at 250-{GeV}/c

Decay distributions in the reaction k+ p ---> k*0(1420) delta++ at 5 gev/c and quark model predictions

STUDY OF THE REACTION K+ P ---> LAMBDA P X AT 32-GeV/c. (IN RUSSIAN)

UPPER LIMITS ON PRODUCTION CROSS-SECTIONS OF CHARMED PARTICLES IN K+ p INTERACTIONS AT 32-GeV/c

K*+ (892) AND rho0 PRODUCTION WITH MESON AND BARYON TRIGGERS IN THE FRAGMENTATION PROCESSES IN K+ p INTERACTIONS AT 32-GeV/c

GENERAL FEATURES OF MULTIPARTICLE REACTIONS K+ p ---> K+ p 3 pi+ 3 pi- AND K+ p ---> K+ p 4 pi+ 4 pi- at 32-GeV/c

A Study of Inclusive $\phi$ Meson Production in Association With Other Particles in $K^+ p$ Reactions at 32-{GeV}/$c$

STUDY OF PROTON DIFFRACTIVE EXCITATION PROCESSES IN REACTION K+ p ---> K+ p pi+ pi- AT 32-GeV/c