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DOE OSTI · 1177853

Nuclear Data Sheets for A = 239

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Abstract

Spectroscopic data and level schemes from radioactive decay and nuclear reaction studies are presented here for all nuclei with mass number A=239. In general, a relatively small amount of new data on this mass chain has been reported since the previous evaluation in 2003. However, special evaluations, such as ''Database of prompt gamma rays from slow neutron–capture from elemental analysis'' (2007ChZX), have provided additional precise data for levels in 29 U. Also, new Coulomb excitation measurements in 239 Pu have extended the knowledge of the 1/2[631] rotational band up to Jπ=(55/2+)Jπ=(55/2+), and that of the octupole vibrational band up to Jπ=(53/2-)Jπ=(53/2-). For historical knowledge it is worth mentioning the report on the “Discovery of isotopes of the transuranium elements with 93 <= Z <= 98'' (2013Fr02), where the information for elements Np, Pu, Am, and Cf with mass number A=239 is presented. The alpha hindrance factors (HF) presented in this evaluation were calculated using values of the radius parameter (r 0 ) interpolated from those for even–even adjacent nuclei given by 1998Ak04.

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BibTeXRIS

Browne, E., Tuli, J. K.. 2014-11-18. Nuclear Data Sheets for A = 239. https://doi.org/10.1016/j.nds.2014.11.003

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