A new software package, the Fission Induced Electromagnetic Response (FIER) code, has been developed to analytically predict delayed γ-ray spectra following fission. FIER uses evaluated nuclear data and solutions to the Bateman equations to calculate the time-dependent populations of fission products and their decay daughters resulting from irradiation of a fissionable isotope. These populations are then used in the calculation of γ-ray emission rates to obtain the corresponding delayed γ-ray spectra. FIER output was compared to experimental data obtained by irradiation of a 235U sample in the Godiva critical assembly. This investigation illuminated discrepancies in the input nuclear data libraries, showcasing the usefulness of FIER as a tool to address nuclear data deficiencies through comparison with experimental data. FIER provides traceability between γ-ray emissions and their contributing nuclear species, decay chains, and parent fission fragments, yielding a new capability for the nuclear science community.

Measurements of beta-delayed gamma-ray spectra following 14-MeV neutron-induced fissions of 232Th, 238U, and 237Np were conducted at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron. Spectra were collected for times ranging from 1 min to 14 h after irradiation. Intensity ratios of gamma-ray lines were extracted from the data that allow identification of the fissioning isotope.© 2013 Elsevier B.V. All rights reserved.

The nuclear reactions C12(C12,α)Ne20, C12(C12,p)Na23, and C12(C12,n)Mg23 are the primary reactions in carbon burning, which occurs as part of several stellar processes. The Gamow window, which describes the energy range where most of these reactions take place, is typically around 1.5 MeV in the center-of-mass frame. Direct measurements of the cross sections at this energy are difficult due to the large Coulomb barrier present between the carbon nuclei; however, a successful surrogate measurement can provide the branching ratios between these reactions while avoiding the C12+C12 Coulomb barrier. An experiment was performed using inelastic scattering of 40 MeV α particles on Mg24 as a possible surrogate for the C12+C12 compound nucleus.