Photodisintegration cross section of beryllium near threshold
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چکیده
9 The cross section for photoneutron production in Be at energies of 1. 692, 1. 720, and 1. 78 Mev has been investigated using radioisotope gamma-ray sources. Neutron counting was by manganous sulfate bath and a long counter. Gamma-ray counting was by a scintillation spectrometer consisting of a Nal(Tl) scintillation crystal and a 256-channel pulse^height analyzer. The following results were obtained: a l 692 = 1 ' 35 ± °'° 8 mb 3 = 0. 763 ± 0.022 a 1.692 g l. 78 a 1.692 = 0.617 ± 0.013 A theoretical treatment of the P-*-S transition near threshold using square-well potentials is also presented.
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