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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.

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).

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ANALYSIS OF RAPIDITY DISTRIBUTION OF pi MESONS IN pi- p AND pi- C-12 REACTIONS BY MEANS OF THE FOURIER ALGORITHM

RAPIDITY DISTRIBUTIONS SCALING IN pi- p INTERACTIONS AT P (pi-) = 40-GeV/c

Study on Correlations in $\pi^-$ C-12 Interactions at $P$ ($\pi^-$) = 40-{GeV}/$c$ in Cumulative Region

Isobar Production Inclusive Cross-sections in $\pi^-$ C-12 Interactions at $P$ ($\pi^-$) = 40-{GeV}/$c$

Production of Particles With Big Transverse Momenta in $\pi^-$ Meson - Nucleon and $\pi^-$ Meson - Nucleus Interactions at 40-{GeV}/$c$

Production of Slow $\pi^0$ Mesons in $\pi^-$ C-12 Interactions at $P$ ($\pi^-$) = 40-{GeV}/$c$

The Study of Effective Mass Spectra of $\pi p$ Pairs in $\pi^-$ C-12 Interactions at $P$ ($\pi^-$) = 40-{GeV}/$c$

Study of pi- n and pi- C-12 Interactions Involving Strange Particles at the Momentum of 40-GeV/c

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

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