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Study of t(z)=3/2 delta(1238) production in p p interactions at 6.6 gev/c

Colton, E. ; Kirschbaum, A.R. ;

Phys.Rev.D 6 (1972) 95-105, 1972.

Inspire Record 74040 DOI 10.17182/hepdata.22248

|Tz|=32Δ(1238) systems are studied from the standpoint of direct production utilizing experimental data on the reactions pp→pπ+n, pp→pπ+π−p, pp→pπ+π−π0p, and pp→pπ+π−π+n. Resonance-production total and differential cross sections are presented, in addition to the decay density-matrix elements. It is demonstrated that the experimentally defined Δ(1238) systems are not characterized solely by spin-parity 32+, and that corresponding elements of the density matrices of both pπ+ and π−n cases generally behave in a similar manner with increasing c.m. angle. Additional detailed studies of the t-channel moments are presented for peripherally produced πN systems as a function of both c.m. angle and πN invariant mass. Dynamical differences are observed between the pπ+ and nπ− moments for the very peripheral data. One-pion-exchange-model predictions are compared with the peripheral pπ+ moments and with several invariant-mass distributions from the pp→pπ+π−p data. Complications arising from the presence of two pπ+ combinations in the four- and five-body final-state data are discussed.

1 data table

Table 1

No description provided.

Search for narrow resonances in the r region

Bowen, D. ; Earles, D. ; Faissler, W. ; et al.

Phys.Rev.Lett. 29 (1972) 890-893, 1972.

Inspire Record 75434 DOI 10.17182/hepdata.21418

We report on a measurement of the missing-mass, (mm)−, spectrum from the reaction π−+p→(mm)−+p at 8 GeV. The data contain 6500 events in the R peak (M2=2.72±0.02 GeV2, Γ=139±31 MeV). The R shape is consistent with either a single Breit-Wigner or several wide resonances, as suggested by bubble-chamber experiments, but inconsistent with the series of narrow resonances reported by the CERN missing-mass group.

1 data table

Table 1

No description provided.

Inelastic electron proton scattering at small four-momentum transfers as a test of finite-energy sum rules

Moritz, J. ; Schmidt, K.H. ; Wegener, D. ; et al.

Nucl.Phys.B 41 (1972) 336-352, 1972.

Inspire Record 75163 DOI 10.17182/hepdata.45250

The twofold differential cross section for the inelastic scattering of electrons on protons wa was measured as a function of the scattered electron energy for an electron scattering angle of 12°. The kinematic region covered in this experiment was 0.3 (GeV/ c ) 2 < q 2 < 1.0 (GeV/ c ) 2 and W < 2.9 GeV. The Bloom-Gilman as well as the constant scattering angle sum rule of Rittenberg and Rubinstein were tested.

5 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (3.7 TO 5////UNCERTAINTIES IN TARGET DENSITY, TARGET DIAMETER, SOLID ANGLE, E- SCATTERING ANGLE, INCIDENT E- ENERGY, DEAD TIME CORRECTIONS, CONSTANT OF FARADAY-CUP INTEGRATOR EFFICIENCY OF SPARK CHAMBERS, RADIATIVE CORRECTIONS).

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A STUDY OF THE STRONG INTERACTION FORM-FACTORS FOR K0(L) ---> pi mu neutrino AND K0(L) ---> pi electron neutrino

Dally, E. ; Innocenti, P. ; Seppi, E. ; et al.

Phys.Lett.B 41 (1972) 647-651, 1972.

Inspire Record 74541 DOI 10.17182/hepdata.28214

We have extracted the strong interaction form factors from K o e3 and K o μ3 data of our previously reported K o L experiment in a manner which does not assume an explicit q 2 = ( p K − p π ) 2 dependence. We present the unparameterized form factors ƒ + (q 2 ) from the K o L → πeν and K o L → πμν modes and ƒ o (q 2 ) and ξ ( q 2 ) from the K o L → πμν data. A comparison of these unparameterized results is made with the results of the Dalitz plot analyses.

1 data table

Table 1

The conventional form factor f+ is studied.

p p Interactions at 303-GeV/c: Multiplicity and Total Cross-Section.

Dao, F.T. ; Gordon, D. ; Lach, J. ; et al.

Phys.Rev.Lett. 29 (1972) 1627-1630, 1972.

Inspire Record 73776 DOI 10.17182/hepdata.21429

In an exposure of the 30-in. hydrogen bubble chamber to a 303−GeVc proton beam, 2245 interactions have been observed. The measured total cross section is 39.0±1.0 mb and the average charged particle multiplicity 〈nch〉=8.86±0.16.

1 data table

Table 1

TOPOLOGICAL CROSS SECTIONS.

Small Angle Elastic Proton Proton Scattering from 25-GeV to 200-GeV.

Bartenev, V. ; Kuznetsov, A. ; Morozov, B. ; et al.

Phys.Rev.Lett. 29 (1972) 1755-1758, 1972.

Inspire Record 73778 DOI 10.17182/hepdata.21428

We have measured the differential cross section for small angle p−p scattering from 25 to 200 GeV incident energy and in the momentum transfer range 0.015<|t|<0.080 (GeVc)2. We find that the slope of the forward diffraction peak, b(s), increases with energy and can be fitted by the form b(s)=b0+2α′ lns, where b0=8.3±1.3 and α′=0.28±0.13 (GeVc)−2. Such dependence is compatible with the data existing both at higher and lower energies. We have also obtained the energy dependence of the p−p total cross section in the energy range from 48 to 196 GeV. Within our errors which are ± 1.1 mb the total cross section remains constant.

2 data tables

Table 1

No description provided.

Table 2

THE TOTAL CROSS SECTION IS NORMALIZED TO 38.5 +- 0.1 MB AT 48 GEV. IT HAS BEEN DERIVED USING THE OPTICAL THEOREM FROM THE EXTRAPOLATED FORWARD ELASTIC CROSS SECTION AND WITH ALPHA = -0.09.

Average charged particle multiplicity and topological cross-sections in 50-GeV/c and 69-GeV/c p p interactions

Ammosov, V.V. ; Boitsov, V.N. ; Ermolov, P.F. ; et al.

Phys.Lett.B 42 (1972) 519-521, 1972.

Inspire Record 74383 DOI 10.17182/hepdata.28174

In an exposure of the chamber Mirabelle at the Serpukhov accelerator, 1 943 interactions at 50 GeV/ c and 8 959 at 69 GeV/ c have been observed. Topological cross sections and charged multiplicity distributions are presented. The average charged multiplicities found are respectively 5.32 ± 0.13 and 5.89 ± 0.07.

1 data table

Table 1

2PRONG INELASTIC CROSS SECTIONS DERIVED BY SUBTRACTION OF OTHER PRONG CROSS SECTIONS AND KNOWN ELASTIC MEASUREMENTS FROM THE TOTAL.

Vector Meson Production by Polarized Photons at 2.8-GeV, 4.7-GeV, and 9.3-GeV

Ballam, Joseph ; Chadwick, G.B. ; Eisenberg, Y. ; et al.

Phys.Rev.D 7 (1973) 3150, 1973.

Inspire Record 73602 DOI 10.17182/hepdata.43496

We present results on vector-meson photoproduction via γp→Vp in the LBL-SLAC 82-in. hydrogen bubble chamber exposed to a linearly polarized photon beam at 2.8, 4.7, and 9.3 GeV. We find ρ0 production to have the characteristics of a diffractive process, i.e., a cross section decreasing slowly with energy and a differential cross section with slope of ∼ 6.5 GeV−2. Within errors the ρ0 production amplitudes are entirely due to natural-parity exchange. s-channel helicity is conserved to a high degree in the γ→ρ0 transition. We find evidence for small helicity-flip amplitudes for ππ pairs in the ρ0 region. Photoproduction of ω mesons is separated into its natural- (σN) and unnatural- (σU) parity-exchange contributions. The Eγ and t dependence and the spin density matrix of the unnatural-parity-exchange contribution are consistent with a one-pion-exchange process. The natural-parity-exchange part has characteristics similar to ρ0 production. At 9.3 GeV the ratio of σ(ρ0) to σN(ω) is ∼ 7. The slope of the φ differential cross section is ∼ 4.5 GeV−2, smaller than that of ρ0 and ω production. Natural-parity exchange is the main contributor to φ production. No evidence for higher-mass vector mesons is found in ππ, πππ, or KK¯ final states. The s and t dependences of Compton scattering as calculated from ρ, ω, and φ photoproduction using vector-meson dominance agree with experiment, but the predicted Compton cross section is too small by a factor of 2.

47 data tables

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Cross sections of common final states for K- p interactions at 8.25-GeV/c

The Athens-Democritus-Liverpool-Vienna collaboration Fry, J.R. ; Brankin, C. ; Matthews, R. ; et al.

Nucl.Phys.B 58 (1973) 408-419, 1973.

Inspire Record 83983 DOI 10.17182/hepdata.8005

Topological and channel cross sections are given for the more common final states produced in K − p interactions at 8.25 GeV/ c together with the single particle inclusive cross sections. We present cross sections for prominent resonances occurring in final states K N (nπ) and find the resonance fractions to be roughly independent of multiplicity.

3 data tables

Table 1

SE FOLDED.

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No description provided.

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