Ausbeuteverh�ltnisse einiger durch Kernphotoreaktionen in Cer und Silber erzeugter Aktivit�ten

Abstract

Samples of metallic silver and cerium-oxide have been irradiated with 3t MeV and 34 MeV bremsstrahlung. Relative yields of the induced activities have been obtained by counting the emitted gamma-quanta or by fi-counting. The yield ratio Y [Ag 1~ (y, n) Ag 1~ m]/y [Agl07 (y, 7r Ag 16~ g] for 34 MeV bremsstrahlung was found to be (0-08 -4-0.02). The corresponding ratio Y ICe a4~ (y, ~z) Celagm]/Y [Ce lt9 (y, n) Ce lagg] at 3t MeV was (0.t94-0.01).

Photoneutron Cross Section in the Giant Resonance Region for Several 82 Neutron Isotones.

“…This activity was 27 9 2k the result of the reaction A1(7, He) Na. For these experiments the activi ty could be ignored because the reaction threshold occurs at 23 Praseodymium-l40 decays approximately fifty percent of the time by emis sion. Although the energy of a single annihilation gamma is below the dis crimination level of the counting system, the sum of energies for both annihilation gamma rays is not.…”

Isomeric yield ratios for the natAg(γ,xn)106m,g;104m,gAg photonuclear reactions induced by 40-, 45-, 50-, 55-, and 60-MeV bremsstrahlung

“…So far, most of the isomeric yield ratios for the nat Ag(c,xn) 106m,g Ag reactions have been measured in the energy range from reaction threshold to about 30-MeV, and only few data measured at higher energies have been reported. Thiep et al [31] measured the isomeric yield ratios for the 107 Ag(c,n) 106m,g Ag reaction in the energy region from 12 to 24 MeV, Fuchs et al [32] measured at 18-MeV, Demekhina et al [20] and Dzhilavyan et al [33] measured at 20 and 30 MeV, Kato [34] and Carver et al [17] measured at 30 MeV, and Sorokhin et al [35] differ by about 320%. Therefore, it is necessary to measure the isomeric yield ratios for the nat Ag(c,xn) 106m,g;104m,g Ag reactions in a broad energy range, especially from just above the GDR region.…”