Gulla Louise Serville Torvund

• Hiver, C.; Wilson, J. N.; Pasqualato, G.; Lebois, M.; Charles, G. & Lopez-Martens, A. [Show all 52 contributors for this article] (2025). HIGH-RESOLUTION STUDIES OF ISOMERIC STATES IN 236U WITH THE nu-Ball2 SPECTROMETER. Acta Physica Polonica B, Proceedings Supplement. ISSN 1899-2358. 18(2). doi: 10.5506/APhysPolBSupp.18.2-A25. Full text in Research Archive Show summary

  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 γ-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 236fU 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 (LaBr3/NaI) from the PARIS Collaboration are added to cover more than 90% of the total solid angle. Additionally, a Doublesided 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.

• Torvund, Gulla Louise Serville; Ernoult, Marc; Courtin, Fanny; Doligez, Xavier; Gjestvang, Dorthea & Siem, Sunniva [Show all 7 contributors for this article] (2025). Multi-MOX: Facilitating plutonium multi-recycling in the French PWR fleet. Annals of Nuclear Energy. ISSN 0306-4549. 223. doi: 10.1016/j.anucene.2025.111641. Full text in Research Archive Show summary

  This study examines the Multi-MOX (MMOX) strategy for plutonium multi-recycling in PWRs using the CLASS fuel cycle simulation tool with assembly-level calculations. MMOX facilitates the multi-recycling of used nuclear fuel by mixing reprocessed plutonium from various sources to create viable fresh nuclear fuel. The strategy significantly curtails the growth of the plutonium inventory, but does not stabilize it entirely in the long term. Although lower fuel burnup reduces plutonium build-up, it increases the production of minor actinides. Comparing MMOX with non-recycling and mono-recycling scenarios, we find that it reduces plutonium inventory by 35% and 19%, respectively. Despite a higher level of minor actinide production, MMOX decreases overall transuranic element production. Additionally, MMOX reduces the need for interim spent fuel storage by a factor of ten compared to non-recycling and by two-thirds compared to mono-recycling, while substantially lowering the age of stockpiled used nuclear fuel.

• Pogliano, Francesco; Larsen, Ann-Cecilie; Goriely, Stéphane; Siess, Lionel; Markova, Maria & Görgen, Andreas [Show all 17 contributors for this article] (2023). Experimentally constrained Ho 165,166 (n,γ) rates and implications for the s process. Physical Review C. ISSN 2469-9985. 107(6). doi: 10.1103/PhysRevC.107.064614. Full text in Research Archive

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• Bjorå, Charlotte Sletten; Bratlie, Sigrid; Torvund, Gulla Louise Serville & Jemterud, Torkild (2026). Abels tårn. [Radio]. Nrk P2. doi: https:/radio.nrk.no/podkast/abels_taarn/l_174596a7-7e42-4578-8596-a77e42d57854. Full text in Research Archive
• Torvund, Gulla Louise Serville; Martinsen, Elise Malmer; Siem, Sunniva; Görgen, Andreas; Beere, William H. Åstorp & Oughton, Deborah H. (2024). Harde fakta om kjernekraft. Full text in Research Archive Show summary

  Er kjernekraft så fantastisk som forkjemperne mener eller så problematisk som motkjemperne påstår? Kom og hør kjernefysikere snakke om teknologien, stråling og atomavfall. Takket være klimakrisen og det stadig større behovet for strøm, er kjernekraft blitt en del av diskusjonen om nye energiformer i Norge. Har du lyst til å lære mer om kjernekraft? Kom og hør kjernefysikere forklare hvordan teknologien fungerer. Du kan stille spørsmål om det du måtte lure på.

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