Decay of 103Ag

Abstract

The reaction 14N + 11B forming a silver compound nucleus and the direct interaction of 107Ag + 14N were utilized to produce the isotope 103Ag. In both instances the 103Ag results from the subsequent evaporation of nucleons from either the Ag compound nucleus or from the 105Ag* reaction intermediate in the case of the direct process. The decay of this isotope was studied using Ge(Li) detectors as well as with standard scintillation counters. The beta- and gamma-ray measurements confirm three beta groups of maximum energies 1.31 ± 0.05 MeV (60%), 1.03 ± 0.05 (30%), and 0.500 ± 0.1 MeV (10%) and gamma rays of energies 0.118, 0.148, 0.235, 0.268, 0.420, 0.540, 0.555, 0.585, 0.655, 0.740, 1.002, 1.1, 1.14, 1.27, 1.36, and 1.56 MeV all decaying with a half-life 1.1 h. Coincidence studies show that the 0.118 MeV gamma ray is in coincidence with 0.148, 0.511, 0.555, 0.740, 1.0, and 1.1 MeV gamma rays; the 0.148 MeV gamma ray with the 0.118, 0.511, 0.555, 0.740, 1.0, and 1.1 MeV gamma rays; the 0.235 MeV gamma ray with the 0.420, 0.511, 0.585, 0.740, 1.04, and 1.13 MeV gamma rays; the 0.540 MeV gamma ray with the 0.511 and 0.820 MeV gamma rays; and the 0.820 MeV gamma ray with the 0.511 and 0.740 MeV gamma rays only. Two beta groups of maximum energies 1.03 and 0.5 MeV are observed to be in coincidence with the 0.148 and 0.268 MeV transitions and with the 0.555 and 0.820 MeV gamma rays as a gate, only the beta group of energy 0.5 ± 0.1 MeV appears. Based on the above observation, a decay scheme of 103Ag is proposed and the results are discussed. The half-life of 118 keV level is measured by delayed coincidence and found to be (1.9 ± 0.4) × 10−9 s indicating an M1 multipolarity for this transition. The mass difference between the ground state of 103Ag and 103Pd is found to be 2.32 MeV.