Alpha-gamma decay studies of No-253 and its daughter products Md-253, Fm-249

作者：Hes**erger F P^*; Antalic S; Ackermann D; Kalaninova Z; Heinz S; Hofmann S; Streicher B; Kindler B; Kojouharov I; Kuusiniemi P; Leino M; Lommel B; Mann R; Nishio K; Saro S; Sulignano B; Venhart M

来源：European Physical Journal A, 2012, 48(5): 75.

DOI：10.1140/epja/i2012-12075-8

Nuclear structure and decay of the isotope No-253 and its decay products Fm-249 and Md-253 were investigated by means of alpha-gamma spectroscopy. Besides the established strong gamma transitions from the 9/2(-)[734] Nilsson level in Fm-249, populated predominantly by the a decay of No-253, into the ground-state (gs) rotational band, a couple of weaker gamma lines (58.3, 129.2, 209.3 and 669.5 keV) were observed and placed into the Fm-249 level scheme. The transition from the 7/2(-) level in Es-249, populated by the alpha decay of Md-253, into the 9/2(+) member of the gs rotational band, so far established for other odd-mass Es isotopes, was observed clearly. GEANT4 simulations were performed to investigate the influence of energy summing between alpha particles and conversion electrons (CE) on the shape of the alpha spectra at different implantation energies, leading to evidence for a weak alpha decay branch of No-253 into the gs of Fm-249 or the ground-state rotational band, respectively.

• 出版日期2012-5