alpha decay of Bk-249(97) and levels in Am-245(95)

作者：Ahmad I^*; Greene J P; Kondev F G; Zhu S; Carpenter M P; Janssens R V F; Boll R A; Ezold J G; Van Cleve S M; Browne E

来源：Physical Review C, 2013, 87(5): 054328.

DOI：10.1103/PhysRevC.87.054328

alpha decay of Bk-249 has been investigated by measuring its alpha and gamma-ray spectra, both in singles and in coincidence modes. The alpha spectrum of a freshly purified Bk-249 sample was measured with a high-resolution, double-focusing magnetic spectrometer. gamma singles, gamma-gamma coincidence, and gamma-alpha coincidence spectra were also recorded. The absolute intensity of the 327.45-keV gamma ray has been determined to be (1.44 +/- 0.08) x 10(-5)% per Bk-249 decay. Assignments of previously known single-particle states were confirmed. A new rotational band was identified in the alpha singles spectrum and Am K x rays have been observed in its decay. This single-particle state, with an energy of 154 keV, has been assigned to the 3/2(-)[521] Nilsson state. This is the lowest excitation energy for this orbital in any Am nucleus. More precise energies and intensities of the Bk-249 alpha groups and gamma-ray transitions are provided.

• 出版日期2013-5-22
• 单位中国社会科学院