Measurement of fission yields from the²⁴¹Am(2n_th,f) reaction at the Lohengrin Spectrometer

Abstract

Résumé. The study of fission yields has a major impact on the characterization and understanding of the fission process and is mandatory for reactor applications. While the yields are known for the major actinides ( 235 U, 239 Pu) in the thermal neutron-induced fission, only few measurements have been performed on 242 Am. This paper presents the results of a measurement at the Lohengrin mass spectrometer (ILL, France) on the reaction 241 Am(2n th ,f): a total of 41 mass yields in the light and the heavy peaks have been measured and compared with the fission process simulation code GEF. Modus operandi and first results of a second experiment performed in May 2013 on the same reaction but with the goal of extracting the isotopic yields are presented as well: 8 mass yields were re-measured and 18 isotopic yields have been investigated and are being analyzed. Results concerning the kinetic energy and its comparison with the GEF Code are also presented in this paper.

Stopping power of fission fragments in thin Mylar and nickel foils

“…For mass 140 and 144, the isobaric composition is, as explained before, strongly perturbed by the presence of a nsisomeric state. We observed in previous gamma-ray spectrometry measurements performed at Lohengrin that at high ionic charge setting beams of these two masses are essentially pure Cs [46].…”

Measurements of $$^{233}$$U$$(\text {n}_{\text {th}},\text {f})$$ fission product mass yields with the LOHENGRIN recoil mass spectrometer

“…In this section, we present how fission product mass yields were historically measured with the LOHENGRIN recoil spectrometer. In the past, a focus on the E k , q correlation was made to account for it as a systematic uncertainty [22][23][24][25] or an external corrective parameter [26,27]. In this work, a new measurement methodology is proposed.…”