Regular Article - Experimental Physics
Fission resonances observed in the Np(d,pf) reaction and the fission barrier topology of Np
Institute for Nuclear Research (ATOMKI), P.O. Box 51, 4001, Debrecen, Hungary
2 Technische Universtität München, 85748, Garching, Germany
3 Ludwig Maximilans Universtität München, 85748, Garching, Germany
4 Department of Physics, University of Oslo, 0316, Oslo, Norway
Accepted: 13 January 2022
Published online: 2 February 2022
The fission probability of Np was measured as a function of the excitation energy in the energy range of E MeV in order to search for transmission fission resonances. A radioactive Np target was bombarded with deuterons of E = 12 MeV, whereas the energy of the protons was analyzed with a superior resolution of E = 8 keV. The experiment was performed at the Tandem accelerator of the Maier-Leibnitz Laboratory in Garching employing the Np(d,pf) reaction. A group of fission resonances has been observed at excitation energies between E MeV, which could be ordered into three (superdeformed) rotational bands with a rotational parameter of keV, and identified as the first direct observation of transition states composing rotational bands in an odd-odd nucleus as they appear above the top of the outer fission barrier. Nuclear reaction code (talys1.95) calculations were also performed to extract the multi-humped fission barrier parameters of Np by fitting them to the experimental data of the present (d,pf) and previous (n,f) experiments. The extracted barrier parameters also support the above interpretation of the observed resonances.
© The Author(s) 2022
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.