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LARGE ANGLE HIGH-ENERGY PHOTOPRODUCTION OF SINGLE pi+ MESONS FROM LIQUID HYDROGEN

Anderson, Robert L. ; Gottschalk, B. ; Gustavson, D. ; et al.

Phys.Rev.Lett. 30 (1973) 627, 1973.

Inspire Record 80994 DOI 10.17182/hepdata.3371

We have measured angular distributions for single photoproduced π+ mesons at 4.0-, 5.0-, and 7.5-GeV incident photon energies and at lab angles from 11° to 66° with the Stanford Linear Accelerator Center 8-GeV spectrometer. Combined with previous Stanford Linear Accelerator Center results, this gives complete angular coverages for this range of energies. The data show the usual "t" and "u" diffraction peaks and a "central plateau" region dropping as S−7.3.

1 data table match query

Table 1

No description provided.

Backward electron-deuteron scattering below 280 mev

Ganichot, D. ; Grossetete, B. ; Isabelle, D.B. ;

Nucl.Phys.A 178 (1972) 545-562, 1972.

Inspire Record 75366 DOI 10.17182/hepdata.8775

We measured the elastic and inelastic scattering of electrons on deuterium at 180° for four incident energies (70, 140, 210 and 280 MeV). The data were analysed with a technique allowing an accurate comparison between experiment and theory. We observed a good agreement for the inelastic data with the expected cross section, using the presently available models and nucleon form factors. The experimental elastic cross section is systematically larger than the predicted cross sections.

16 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Vector meson production by 4.3 GeV polarized photons on deuterium

Eisenberg, Y. ; Haber, B. ; Kogan, E. ; et al.

Nucl.Phys.B 104 (1976) 61-97, 1976.

Inspire Record 98707 DOI 10.17182/hepdata.35922

Cross sections for γd and γn interactions and photoproduction of ϱ 0 and ω are studied at 4.3 GeV, using a linearly polarized photon beam in a deuterium bubble chamber. We find that σ T (γ n ) ⋍ σ T (γ p ) within about 5% and that the γn average charge multiplicity is lower than γp by 0.42±0.09. About 4000 ϱ 0 events and 70 coherent ω events are observed. We present total and differential cross sections for both xoherent and incoherent ϱ 0 production on deuterium, as well as decay angular distributions and density-matrix elements. We find that the t -channel isospin-one exchange amplitude in γ N → ϱ 0 N (e.g. A 2 exchange) is at most 5–13% of the dominant isoscalar amplituds. The ϱ 0 production mechanism is dominantly s -channel helicity-conserving (SHC) on both neutrons and protons. We find that relative to the SHC amplitudes, the single and double helicity-flip amplitudes at the γϱ 0 vertex are of the order of 10–15% for | t | > 0.25 GeV 2 , and have the same sign on both nucleons. This shows that helicity-flip is mainly due to isoscalar exchanges. The ratio of ω to ϱ 0 coherent forward cross sections is found to be 0.16±0.04. The natural-parity exchange part of γ N → ω N is strongly dominated by isoscalar exchanges, and the magnitude of the isovector-exchange is consistent with zero.

5 data tables match query

Table 1

TOPOLOGICAL CROSS SECTIONS AND AVERAGE CHARGE MULTIPLICITIES GIVEN IN TABLE 1.

Table 2

'PARAMETRIZATION'.

Table 3

No description provided.

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The Charge Form Factor of the Proton at a Momentum Transfer of 75 F$^-^2$

Bartel, W. ; Dudelzak, B. ; Krehbiel, H. ; et al.

Phys.Lett.B 25 (1967) 236-237, 1967.

Inspire Record 1333753 DOI 10.17182/hepdata.29448

The proton form factors GE(q2) and GM(q2) are determined at q2 = 75fm−2.

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Photoproduction of rho0 on hydrogen with tagged photons between 4 and 6 gev

Struczinski, W. ; Dittmann, P. ; Eckardt, V. ; et al.

Nucl.Phys.B 47 (1972) 436-444, 1972.

Inspire Record 84477 DOI 10.17182/hepdata.29528

We have measured the reaction γ p → p π + π − in the DESY 1 m Streamer Chamber. The dominant ϱ o production is analyzed in terms of various models.

6 data tables match query

Table 1

No description provided.

Table 2

FOR ALL EVENTS.

Table 3

FOR ALL TWO PION EVENTS.

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Photoproduction of the psi (3100) Meson at 11-GeV

Gittelman, B. ; Hanson, K.M. ; Larson, D. ; et al.

Phys.Rev.Lett. 35 (1975) 1616, 1975.

Inspire Record 99727 DOI 10.17182/hepdata.21158

The photoproduction of the ψ(3100) meson from a beryllium target has been measured using an 11.8-GeV bremsstrahlung beam. The energy and angular dependence of the measured spectra may be obtained from an elastic nucleon cross section of the form dσdt=(1.01±0.20)exp[(1.25±0.20)t] nb/GeV2. This cross section is exceedingly small in comparison with those of the other vector mesons.

1 data table match query

Table 1

ELECTRON PAIR PRODUCTION FROM BERYLLIUM TARGET. ELASTIC CROSS SECTION VALUE ALLOWS FOR SYSTEMATIC UNCERTAINTIES AND POSSIBLE INELASTIC CONTRIBUTIONS. -TMIN = 0.41 GEV**2.

pi0 and rho0 Photoproduction from 6-GeV to 18-GeV

Barish, B. ; Gomez, R. ; Kreinick, D. ; et al.

Phys.Rev.D 9 (1974) 566, 1974.

Inspire Record 94529 DOI 10.17182/hepdata.21952

Differential cross sections for π0 and ρ0 photoproduction from protons have been measured at photon energies 6, 12, and 18 GeV and momentum transfers 0.5 to 3 (GeVc)2.

3 data tables match query

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

rivet Analysis
Charged Meson Pair Production in $\gamma \gamma$ Interactions

Boyer, J. ; Burke, D.L. ; Butler, F. ; et al.

Phys.Rev.Lett. 56 (1986) 207, 1986.

Inspire Record 220003 DOI 10.17182/hepdata.20236

The cross section for the production of π+π− or K+K− pairs in γγ interactions is measured for mππ between 1.7 and 3.5 GeV/c2 and for two intervals of γγ center-of-mass scattering angle. Results are compared with predictions of a QCD model.

2 data tables match query

Table 1

Data read off graph.

Table 2

Data read off graph.

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 match query

Table 1

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

Table 2

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

Table 3

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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