0 50 60 01 v 2 1 4 Ju l 2 00 5 Near - threshold measurement of the 4 He ( γ , n ) reaction
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چکیده
A near-threshold He(γ, n) cross-section measurement has been performed at MAXlab. Tagged photons from 23 < Eγ < 42 MeV were directed toward a liquid He target, and neutrons were detected by time-of-flight in two liquid-scintillator arrays. Seven-point angular distributions were measured for eight photon energies. The results are compared to experimental data measured at comparable energies and Recoil-Corrected Continuum Shell Model, Resonating Group Method, and recent Hyperspherical-Harmonic Expansion calculations. The angle-integrated crosssection data is peaked at a photon energy of about 28 MeV, in disagreement with the value recommended by Calarco, Berman, and Donnelly in 1983.
منابع مشابه
A ug 2 00 5 Near - threshold measurement of the 4 He ( γ , n ) reaction
A near-threshold He(γ, n) cross-section measurement has been performed at MAXlab. Tagged photons from 23 < Eγ < 42 MeV were directed toward a liquid He target, and neutrons were detected by time-of-flight in two liquid-scintillator arrays. Seven-point angular distributions were measured for eight photon energies. The results are compared to experimental data measured at comparable energies and ...
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تاریخ انتشار 2005