Measurements of -ray emission probabilities of Am and Np

Terada, Kazushi; Nakamura, Shoji  ; Nakao, Taro; Kimura, Atsushi   ; Iwamoto, Osamu  ; Harada, Hideo   ; Takamiya, Koichi*; Hori, Junichi*

-ray emission probabilities of Am and Np have been precisely measured with - and -ray spectroscopic methods. The activities of Am samples were determined by measuring alpha particles using a Si semiconductor detector. -rays emitted from the samples were measured with a planar type High-Purity Germanium (HPGe) detector. An efficiency curve of the Ge detector was derived with uncertainties of 0.7% from 50 to 1332 keV and 1.3% below 50 keV by combining measured efficiencies and Monte Carlo simulation. The -ray emission probabilities for the major -rays of these nuclides were determined with uncertainties less than 1.2%.