Measurement Of Hadronic Cross Section Research Articles

Virtual-photon shadowing in nuclei and photon structure

The “standard” two-component (point-like plus VMD) model for the structure of photons seems to be in conflict with recent measurements of total hadronic cross sections for virtual photons incident on several nuclei. In this letter we show that the model works provided that certain off-shell effects, suggested within the framework of QCD, are properly taken into account.

Measurement of hadronic exclusive cross sections in e +e − annihilation from 1.42 to 2.20 GeV

Total cross sections for reactions e +e −→ π + π − π 0, π + π − π 0, 2 π +2 π − π 0, 2 π +2 π −2 π 0, 3 π +3 π − have been measured in the total c.m. energy range 1.42–2.20 GeV. Partial R= σ had/ σ σ + μ − values for two and four produced charged pions, and cross sections for positive and negative G-parity states are also reported.

Measurement of total hadronic photoproduction cross sections on the nuclei C, Cu and Pb for energies Eγ=(12–30) GeV

The total cross section of hadron photoproduction on C, Cu and Pb nuclei is measured for six energy values in the range 12–30 GeV. The obtained cross-section values for C and Cu nuclei have a weak energy dependence at high energies (above 20 GeV). The cross section for the Pb nucleus is somewhat higher in comparison with that expected, and energy dependence is not observed. The A-dependence of the effective number of hadrons agrees with VDM predictions.

Measurement of total hadronic photoabsorption cross section on carbon from 14 to 34 GeV

The data on total cross section of hadronic photoabsorption in carbon nuclei as obtained by conventional tagged photon method are given for five values of energy in 14–34 GeV interval. A slight drop of cross section curve with the increase in energy is observed, indicating the contribution of ϱ′-meson to the total cross section.