High-resolution Studies of Isomeric States in $^{236}$U with the nu-Ball2 Spectrometer
2 IRMM - JRC Institute for Reference Materials and Measurements [Geel]
3 UNIS - University of Surrey
4 NPL - National Physical Laboratory [Teddington]
5 UW - Uniwersytet Warszawski [Polska] = University of Warsaw [Poland] = Université de Varsovie [Pologne]
6 Vinča Institute of Nuclear Sciences
7 University of Novi Sad
8 University of Belgrade [Belgrade]
9 TU Darmstadt - Technische Universität Darmstadt - Technical University of Darmstadt [Darmstadt]
10 UiO - University of Oslo
11 UNINA - University of Naples Federico II = Università degli studi di Napoli Federico II
12 PAN - Polska Akademia Nauk = Polish Academy of Sciences = Académie polonaise des sciences
13 INFN, Sezione di Bologna - Istituto Nazionale di Fisica Nucleare, Sezione di Bologna
14 UNIMI - Università degli Studi di Milano = University of Milan
15 IFIC - Instituto de Fisica Corpuscular
16 Horia Hulubei National Institute for Physics and Nuclear Engineering
17 IPHC - Institut Pluridisciplinaire Hubert Curien
18 Taras Shevchenko National University of Kyiv
19 IP2I Lyon - Institut de Physique des 2 Infinis de Lyon
20 GANIL - Grand Accélérateur National d'Ions Lourds
- Fonction : Auteur
- PersonId : 737836
- IdHAL : joa-ljungvall
- ORCID : 0000-0003-1938-1889
- IdRef : 234661593
- Fonction : Auteur
- PersonId : 740189
- IdHAL : sylvie-delpech
- ORCID : 0000-0002-2406-2041
- IdRef : 158107071
- Fonction : Auteur
- PersonId : 181517
- IdHAL : olivier-stezowski
- ORCID : 0000-0002-3387-8253
- IdRef : 149738064
Résumé
Fission shape isomers (SI) are poorly understood metastable states characterized by a second super-deformed potential energy minimum coexisting with normally-deformed states in the low-spin regime. Although many such isomers have been observed in the actinide region, our understanding of the states of the second minimum remains very limited. For most SIs, the only available information is their half-life, determined via their exclusive decay mode, delayed fission. However, the interesting possibility of a competing branch of \(\gamma \)-back decay towards normally-deformed states opens up as the number of protons decreases and the fission barrier becomes harder to penetrate, uranium isotopes being the heaviest candidates. In this context, two experiments were performed to study \(^{236f}\)U using the nu-Ball2/PARIS spectrometer at the ALTO facility of IJCLab. The nu-Ball2 setup consists of 24 High Purity Germanium (HPGe) Clovers and 64 phoswiches (LaBr\(_3\)/NaI) from the PARIS Collaboration are added to cover more than 90% of the total solid angle. Additionally, a Double-sided Silicon Stripped Detector (DSSD) was used to measure the energy of outgoing light-charged particles. The state-of-the-art fully digital FASTER electronics allowed triggerless data acquisition at high data rates. The selectivity of this setup enabled us to probe rare decays with sub-microbarn cross sections.
| Origine | Fichiers éditeurs autorisés sur une archive ouverte |
|---|---|
| Licence |