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The differential cross sections for the photoproduction reactions γ+p→π++n, γ+p→K++Λ0, and γ+p→K++Σ0 have ben measured for incident laboratory photon energies between 3.4 and 4.0 GeV and for meson center-of-mass angles from about 25° to 45°. The reactions were studied by observing only the charged mesons. The momenta, velocities, and angles of the mesons were measured with a magnetic spectrometer, and the equivalent of nearly monochromatic gamma rays was obtained by performing bremsstrahlung subtractions. The cross sections agree with the inequality predicted from unbroken SU(3). The measured behavior of dσdt as a function of t shows similarities to that observed in studies of mesonnucleon scattering.

6 data tables

Table 1

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Table 2

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Table 3

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Total hadronic (gamma, p) and (gamma, d) cross-sections from 4 to 18 gev/c

Caldwell, David O. ; Elings, V.B. ; Hesse, W.P. ; et al.

Phys.Rev.Lett. 25 (1970) 609-612, 1970.

Inspire Record 62881 DOI 10.17182/hepdata.21598

Photoabsorption cross sections in hydrogen and deuterium have been measured from 3.7 to 17.9 GeV. The energy dependences are similar to those of strong-interaction total cross sections, as expected from the vector-meson-dominance model. The magnitude of σT(γp) can be compared with data from γp→ρ0p to determine a γ−p coupling constant, γρ24π=0.37±0.03. This value disagrees with that obtained on the ρ mass shell, and hence there is only qualitative agreement with the vector-meson-dominance model.

1 data table

Table 1

Axis error includes +- 1/1 contribution (CORRECTION OF ACCEPTANCE, POSSIBLE LOSSES, ETC).

ASYMMETRY MEASUREMENTS IN PION PHOTOPRODUCTION BY POLARIZED PHOTONS IN THE ENERGY RANGE FROM 250-MeV TO 600-MeV

Antufev, Yu.P. ; Agranovich, V.L. ; Ganenko, V.B. ; et al.

PRINT-70-2307, 1970.

Inspire Record 1105361 DOI 10.17182/hepdata.75432

None

1 data table

Table 1

No description provided.

Coincidence measurements of single pi+ electroproduction

Brown, C.N. ; Canizares, C.R. ; Cooper, W.E. ; et al.

Phys.Rev.Lett. 26 (1971) 987-991, 1971.

Inspire Record 69020 DOI 10.17182/hepdata.21506

We have studied the reaction e−+p→e−+π++n by detecting the final electron and pion in coincidence. Data are presented in the region of virtual photon mass squared from -0.18 to -1.2 GeV2, and virtual photoproduction center-of-mass energy and angle from 1.85 to 2.50 GeV and 0 to 20°, respectively.

12 data tables

Table 1

No description provided.

Table 2

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Table 3

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Asymmetry of the cross section of gamma d ---> pi0 d reaction at photon energy of 350 mev

Ganenko, V.B. ; Gorbenko, V.G. ; Zhebrovskii, Yu.V. ; et al.

Pisma Zh.Eksp.Teor.Fiz. 18 (1973) 483-486, 1973.

Inspire Record 87826 DOI 10.17182/hepdata.39926

None

1 data table

Table 1

No description provided.

Total Hadronic Photoabsorption Cross-Sections on Hydrogen and Complex Nuclei from 4-GeV to 18-GeV

Caldwell, David O. ; Elings, V.B. ; Hesse, W.P. ; et al.

Phys.Rev.D 7 (1973) 1362, 1973.

Inspire Record 83727 DOI 10.17182/hepdata.22181

Final total cross sections are given for a counter experiment at SLAC on hadronic photon absorption in hydrogen, deuterium, carbon, copper, and lead at incident energies from 3.7 to 18.3 GeV. Some of the nucleon cross sections have been revised and the C, Cu, and Pb data from 3.7 to 7.4 GeV have not been reported previously. The cross sections for complex nuclei vary approximately as A0.9 in our energy range, indicating that the photon interacts, at least partially, as a strongly interacting particle. The energy dependences of the proton and neutron cross sections are also similar to those of hadron-nucleon cross sections and hence may be fitted by a typical Regge parametrization, yielding σT(γp)=(98.7±3.6)+(65.0±10.1)ν−12 μb and σT(γn)=(103.4±6.7)+(33.1±19.4)ν−12 μb, where ν is the photon energy in GeV. These extrapolate to the same value at infinite energy, consistent with Pomeranchukon exchange, and the energy-dependent part yields an isovector-to-isoscalar-exchange ratio of 0.18 ± 0.06. While these observations are qualitatively consistent with vector meson dominance, quantitatively vector dominance fails in relating our results to ρ photo-production on hydrogen or to experiments determining the ρ-nucleon cross section. Vector dominance cannot be rescued by assuming that the ρ-photon coupling constant depends on the photon mass. Instead, an additional short-range interaction is apparently required, possibly due to a heavy (≳ 2 GeV / c2) vector meson or to a bare-photon interaction. The additional interaction accounts for approximately 20% of the total photoabsorption cross section.

3 data tables

Table 1

DATA ARE GROUPED IN SETS OF FOUR TAGGING ENERGIES FOR EACH INCIDENT POSITRON ENERGY.

Table 2

CROSS SECTIONS FOR EACH INCIDENT POSITRON ENERGY AVERAGED OVER THE FOUR TAGGING ENERGIES.

Table 3

TOTAL CROSS SECTION, EFFECTIVE NUCLEON NUMBER (A-EFF) AND EFFECTIVE ATTENUATION (A-EFF/A) FOR CARBON, COPPER AND LEAD TARGETS. 'SIG(NUCLEON)' IS THE AVERAGE NUCLEON CROSS SECTION.