Sunniva Siem

• Li, Kevin Ching Wei; Neveling, R.; Adsley, P.; Fujita, H.; Papka, P. & Smit, F. D. [Show all 15 contributors for this article] (2024). Understanding the total width of the 3−1 state in 12C. Physical Review C. ISSN 2469-9985. 109(1). doi: 10.1103/PhysRevC.109.015806.
• Magagula, S.P.E.; Malatji, Kgashane Leroy; Wiedeking, M.; Pellegri, L; Beckmann, Kristine Sønstevold & Bello Garrote, Frank Leonel [Show all 17 contributors for this article] (2023). Investigating the strength of the scissors mode in 151Sm. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. doi: 10.1088/1742-6596/2586/1/012070. Full text in Research Archive
• Jivan, H.; Pellegri, Luna; Adsley, P; Bahini, A.; Brummer, J.W. & Donaldson, L. [Show all 29 contributors for this article] (2023). Pygmy Dipole Response in Samarium isotopes. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. doi: 10.1088/1742-6596/2586/1/012088. Full text in Research Archive
• Gjestvang, Dorthea; Wilson, J.N.; Al-Adili, A.; Siem, Sunniva; Gao, Z. & Randrup, J. [Show all 74 contributors for this article] (2023). Examination of how properties of a fissioning system impact isomeric yield ratios of the fragments. Physical Review C. ISSN 2469-9985. 108(6). doi: 10.1103/PhysRevC.108.064602. Full text in Research Archive
• Pasqualato, G; Ansari, S.; Heines, Johannes Sørby; Modamio, Victor; Görgen, Andreas & Beckmann, Kristine Sønstevold [Show all 52 contributors for this article] (2023). Shape evolution in even-mass ^{98 - 104} Zr isotopes via lifetime measurements using the γγ -coincidence technique. European Physical Journal A. ISSN 1434-6001. 59(11). doi: 10.1140/epja/s10050-023-01172-8. Show summary

  The Zirconium (Z = 40) isotopic chain has attracted interest for more than four decades. The abrupt lowering of the energy of the first 2+ state and the increase in the transition strength B(E2; 2+→ 0+) going from 98Zr to 100Zr has been the first example of “quantum phase transition” in nuclear shapes, which has few equivalents in the nuclear chart. Although a multitude of experiments have been performed to measure nuclear properties related to nuclear shapes and collectivity in the region, none of the measured lifetimes were obtained using the Recoil Distance Doppler Shift method in the γγ-coincidence mode where a gate on the direct feeding transition of the state of interest allows a strict control of systematical errors. This work reports the results of lifetime measurements for the first yrast excited states in 98−104Zr carried out to extract reduced transition probabilities. The new lifetime values in γγ-coincidence and γ -single mode are compared with the results of former experiments. Recent predictions of the Interacting Boson Model with Configuration Mixing, the Symmetry Conserving Configuration Mixing model based on theHartree–Fock–Bogoliubov approach and the Monte Carlo Shell Model are presented and compared with the experimental data.

• Tamii, A.; Pellegri, L.; Söderström, P.-A.; Allard, D.; Goriely, S. & Inakura, T. [Show all 82 contributors for this article] (2023). PANDORA Project for the study of photonuclear reactions below A= 60. European Physical Journal A. ISSN 1434-6001. 59(9). doi: 10.1140/epja/s10050-023-01081-w. Full text in Research Archive
• Tveten, Gry Merete; Utsunomiya, H.; Larsen, Ann-Cecilie; Algin, E.; Ari-Izumi, T. & Ay, Kursad Osman [Show all 31 contributors for this article] (2023). New experimental constraint on the W 185 (n,γ) W 186 cross section. Physical Review C. ISSN 2469-9985. 108(2). doi: 10.1103/PhysRevC.108.025804. Full text in Research Archive
• Camera, F.; Isaak, J.; Maj, A. & Siem, Sunniva (2023). AGATA: Nuclear structure advancements with high-energy γ rays. European Physical Journal A. ISSN 1434-6001. 59(7). doi: 10.1140/epja/s10050-023-01076-7. Full text in Research Archive
• Thisse, D.; Lebois, M.; Verney, D.; Wilson, J.N.; Jovančević, N. & Rudigier, M. [Show all 78 contributors for this article] (2023). Study of N= 50 gap evolution around Z= 32 : new structure information for ⁸² Ge. European Physical Journal A. ISSN 1434-6001. 59(7). doi: 10.1140/epja/s10050-023-01051-2.
• Markova, Maria; Larsen, Ann-Cecilie; Tveten, Gry Merete; von Neumann-Cosel, Peter; Eriksen, Tomas Kvalheim & Bello Garrote, Frank Leonel [Show all 16 contributors for this article] (2023). Nuclear level densities and γ -ray strength functions of Sn 111,112,113 isotopes studied with the Oslo method. Physical Review C. ISSN 2469-9985. 108(1). doi: 10.1103/PhysRevC.108.014315. Full text in Research Archive
• 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
• Lewis, R.; Couture, A.; Liddick, S.N.; Spyrou, A.; Bleuel, D.L. & Crespo Campo, Lucia [Show all 18 contributors for this article] (2023). Statistical (n, γ) cross section model comparison for short-lived nuclei. European Physical Journal A. ISSN 1434-6001. 59(3). doi: 10.1140/epja/s10050-023-00920-0. Full text in Research Archive
• Mücher, D.; Spyrou, A.; Wiedeking, M.; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie & Zeiser, Fabio Balthasar [Show all 25 contributors for this article] (2023). Extracting model-independent nuclear level densities away from stability. Physical Review C. ISSN 2469-9985. 107(1). doi: 10.1103/PhysRevC.107.L011602. Full text in Research Archive
• Pogliano, Francesco; Bello Garrote, Frank Leonel; Larsen, Ann-Cecilie; Berg, Hannah Christine; Gjestvang, Dorthea & Görgen, Andreas [Show all 19 contributors for this article] (2023). Observation of a candidate for the M1 scissors resonance in odd-odd Ho 166. Physical Review C. ISSN 2469-9985. 107(3). doi: 10.1103/PhysRevC.107.034605. Show summary

  The γ -strength function and the nuclear level density for the odd-odd, rare-earth nucleus 166 Ho have been extracted from 163 Dy(α, pγ ) 166 Ho data using the Oslo method. A structure at ≈3 MeV in the γ -strength function is interpreted as the M1 scissors resonance. By employing three different methods we find that its strength depends rather strongly on the modeling of the E 1 strength, while its centroid does not. The 166 Ho scissors resonance parameters are consistent with previous results on other rare-earth nuclei.

• Ingeberg, Vetle Wegner; Jones, P.; Msebi, L.; Siem, Sunniva; Wiedeking, M. & Avaa, A.A. [Show all 12 contributors for this article] (2022). Nuclear level density and γ-ray strength function of Ni 63. Physical Review C. ISSN 2469-9985. 106(5). doi: 10.1103/PhysRevC.106.054315. Full text in Research Archive
• Bello Garrote, Frank Leonel; Lopez-Martens, Araceli; Larsen, Ann-Cecilie; Deloncle, I.; Péru, Sophie & Zeiser, Fabio [Show all 38 contributors for this article] (2022). Experimental observation of the M1 scissors mode in ²⁵⁴No. Physics Letters B. ISSN 0370-2693. 834. doi: 10.1016/j.physletb.2022.137479. Full text in Research Archive
• Guttormsen, Magne Sveen; Ay, Kursad Osman; Ozgur, Mustafa; Algin, Emel; Larsen, Ann-Cecilie & Bello Garrote, Frank Leonel [Show all 25 contributors for this article] (2022). Evolution of the γ -ray strength function in neodymium isotopes. Physical Review C. ISSN 2469-9985. 106(3). doi: 10.1103/PhysRevC.106.034314. Full text in Research Archive
• Markova, Maria; Larsen, Ann-Cecilie; von Neumann-Cosel, Peter; Bassauer, Sergej; Görgen, Andreas & Guttormsen, Magne Sveen [Show all 23 contributors for this article] (2022). Nuclear level densities and γ -ray strength functions in Sn 120,124 isotopes: Impact of Porter-Thomas fluctuations. Physical Review C. ISSN 2469-9985. 106(3). doi: 10.1103/PhysRevC.106.034322. Full text in Research Archive
• Pogliano, Francesco; Larsen, Ann-Cecilie; Markova, Maria; Bello Garrote, Frank Leonel; Bjørøen, Marianne Møller & Eriksen, Tomas Kvalheim [Show all 17 contributors for this article] (2022). Indirect measurement of the (n,γ) Sb 127 cross section. Physical Review C. ISSN 2469-9985. 106(1). doi: 10.1103/PhysRevC.106.015804. Full text in Research Archive
• Li, Kevin Ching Wei; Smit, F. D.; Adsley, P.; Neveling, R.; Papka, P. & Nikolskii, E. [Show all 28 contributors for this article] (2022). Investigating the predicted breathing-mode excitation of the Hoyle state. Physics Letters B. ISSN 0370-2693. doi: 10.1016/j.physletb.2022.136928. Full text in Research Archive
• Li, Kevin Ching Wei; Adsley, P; Neveling, R; Papka, P; Smit, F. D & Nikolskii, E [Show all 28 contributors for this article] (2022). Multiprobe study of excited states in 12 C : Disentangling the sources of monopole strength between the energy of the Hoyle state and E x = 13 MeV. Physical Review C. ISSN 2469-9985. doi: 10.1103/PhysRevC.105.024308. Full text in Research Archive
• Naqvi, F.; Karampagia, S.; Spyrou, A.; Liddick, S.N.; Dombos, A.C. & Bleuel, D.l. [Show all 20 contributors for this article] (2022). Total absorption spectroscopy measurement on neutron-rich 74,75Cu isotopes. Nuclear Physics A. ISSN 0375-9474. A1018(122359). doi: 10.1016/j.nuclphysa.2021.122359.
• Gjestvang, Dorthea; Siem, Sunniva; Zeiser, Fabio; Randrup, Jørgen; Vogt, Ramona & Bello Garrote, Frank Leonel [Show all 20 contributors for this article] (2021). The study of prompt fission γ rays at the Oslo Cyclotron Laboratory. The European Physical Journal Conferences. ISSN 2101-6275. doi: 10.1051/epjconf/202125600005. Full text in Research Archive
• Markova, Maria; von Neumann-Cosel, Neumann-Cosel; Larsen, A.C.; Bassauer, S.; Görgen, A. & Guttormsen, Magne Sveen [Show all 25 contributors for this article] (2021). Comprehensive Test of the Brink-Axel Hypothesis in the Energy Region of the Pygmy Dipole Resonance. Physical Review Letters. ISSN 0031-9007. 127(18). doi: 10.1103/PhysRevLett.127.182501. Full text in Research Archive
• Wiedeking, Mathis; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Zeiser, Fabio; Görgen, Andreas & Liddick, Sean N. [Show all 9 contributors for this article] (2021). Independent normalization for gamma-ray strength functions: The shape method. Physical Review C. ISSN 2469-9985. 104(014311). doi: 10.1103/PhysRevC.104.014311. Full text in Research Archive
• Persch, C.F.; DeYoung, P.A.; Lyons, S.; Spyrou, Artemis; Liddick, Sean N. & Naqvi, F. [Show all 27 contributors for this article] (2021). Beta-decay feeding intensity distributions of 71,73Ni. Physical Review C. ISSN 2469-9985. C103(055808). doi: 10.1103/PhysRevC.103.055808. Full text in Research Archive
• Görgen, Andreas; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Siem, Sunniva; Adli, Erik & Edin, Nina Frederike J [Show all 14 contributors for this article] (2021). The Oslo Cyclotron Laboratory. The European Physical Journal Plus. ISSN 2190-5444. 136, p. 1–13. doi: 10.1140/epjp/s13360-021-01150-3. Full text in Research Archive
• Guttormsen, Magne Sveen; Alhassid, Yoram; Ryssens, Wouter; Ay, K.o.; Ozgur, Mustafa & Algin, Emel [Show all 21 contributors for this article] (2021). Strong enhancement of level densities in the crossover from spherical to deformed neodymium isotopes. Physics Letters B. ISSN 0370-2693. 816. doi: 10.1016/j.physletb.2021.136206. Full text in Research Archive
• Wilson, J. N.; Thisse, D; Lebois, Matthieu; Jovančević, Nikola; Gjestvang, Dorthea & Canavan, R [Show all 76 contributors for this article] (2021). Angular momentum generation in nuclear fission. Nature. ISSN 0028-0836. 590, p. 566–570. doi: 10.1038/s41586-021-03304-w.
• Gjestvang, Dorthea; Siem, Sunniva; Zeiser, Fabio; Randrup, Jørgen; Vogt, Ramona & Wilson, Jonathan Nicholas [Show all 19 contributors for this article] (2021). Excitation energy dependence of prompt fission γ-ray emission from 241Pu*. Physical Review C. ISSN 2469-9985. 103(3). doi: 10.1103/PhysRevC.103.034609. Full text in Research Archive Show summary

  Prompt fission γ rays (PFGs) resulting from the 240Pu(d,pf) reaction have been measured as a function of fissioning nucleus excitation energy Ex at the Oslo Cyclotron Laboratory. We study the average total PFG multiplicity per fission, the average total PFG energy released per fission, and the average PFG energy. No significant changes in these characteristics are observed over the range 5.75

• Malatji, Kgashane Leroy; Beckmann, Kristine Sønstevold; Wiedeking, Mathis; Siem, Sunniva; Goriely, Stephane & Larsen, Ann-Cecilie [Show all 21 contributors for this article] (2021). Statistical properties of the well deformed 153,155Sm nuclei and the scissors resonance. Physical Review C. ISSN 2469-9985. 103(1). doi: 10.1103/PhysRevC.103.014309. Full text in Research Archive
• Zeiser, Fabio; Tveten, Gry Merete; Bello Garrote, Frank Leonel; Guttormsen, Magne Sveen; Larsen, Ann-Cecilie & Ingeberg, Vetle Wegner [Show all 8 contributors for this article] (2021). The gamma-ray energy response of the Oslo Scintillator Array OSCAR. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. ISSN 0168-9002. 985. doi: 10.1016/j.nima.2020.164678. Full text in Research Archive
• Pérez Sánchez, R.; Jurado, Beatriz; Meot, V; Roig, O; Dupuis, M & Denis-Petit, D [Show all 21 contributors for this article] (2020). Simultaneous Determination of Neutron-Induced Fission and Radiative Capture Cross Sections from Decay Probabilities Obtained with a Surrogate Reaction. Physical Review Letters. ISSN 0031-9007. 125(12). doi: 10.1103/PhysRevLett.125.122502. Full text in Research Archive
• Kibédi, T.; Alshahrani, B.; Stuchbery, A.E.; Larsen, Ann-Cecilie; Görgen, Andreas & Siem, Sunniva [Show all 20 contributors for this article] (2020). Radiative Width of the Hoyle State from γ -Ray Spectroscopy. Physical Review Letters. ISSN 0031-9007. 125(18). doi: 10.1103/PhysRevLett.125.182701. Full text in Research Archive
• Ingeberg, Vetle Wegner; Siem, Sunniva; Wiedeking, Mathis; Sieja, Kamila; Bleuel, D.l. & Brits, C.P. [Show all 29 contributors for this article] (2020). First application of the Oslo method in inverse kinematics. European Physical Journal A. ISSN 1434-6001. 56. doi: 10.1140/epja/s10050-020-00070-7. Full text in Research Archive Show summary

  The γ-ray strength function (SF) and nuclear level density (NLD) have been extracted for the first time from inverse kinematic reactions with the Oslo method. This novel technique allows measurements of these properties across a wide range of previously inaccessible nuclei. Proton–γ coincidence events from the d(⁸⁷Kr,p)⁸⁶Kr reaction were measured at iThemba LABS and the γSF and NLD in ⁸⁶Kr was obtained. The low-energy region of the γSF is compared to shell-model calculations, which suggest this region to be dominated by M1 strength. The γSF and NLD are used as input parameters to Hauser–Feshbach calculations to constrain (n,γ) cross sections of nuclei using the TALYS reaction code. These results are compared to ⁸⁶Kr(n,γ) data from direct measurements.

• Kawano, T.; Cho, Y.S.; Dimitriou, Paraskevi; Filipescu, D. M.; Iwamoto, N. & Plujko, V. [Show all 28 contributors for this article] (2020). IAEA Photonuclear Data Library 2019. Nuclear Data Sheets. ISSN 0090-3752. 163, p. 109–162. doi: 10.1016/j.nds.2019.12.002.
• Wrzosek-Lipska, K.; Rezynkina, K.; Bree, N.; Zielińska, M.; Gaffney, L.P. & Petts, A. [Show all 70 contributors for this article] (2019). Electromagnetic properties of low-lying states in neutron-deficient Hg isotopes: Coulomb excitation of ¹⁸²Hg, ¹⁸⁴Hg, ¹⁸⁶Hg and ¹⁸⁸Hg. European Physical Journal A. ISSN 1434-6001. 55(8), p. 1–23. doi: 10.1140/epja/i2019-12815-2.
• Krzysiek, Mateusz; Utsunomiya, Hiroaki; Gheorghe, Ioana; Filipescu, Dan Mihai; Renstrøm, Therese & Tveten, Gry Merete [Show all 19 contributors for this article] (2019). Photoneutron cross-section measurements for 165HO by the direct neutron-multiplicity sorting at Newsubaru . Acta Physica Polonica B. ISSN 0587-4254. 50(3), p. 487–494. doi: 10.5506/APhysPolB.50.487.
• Guttormsen, Magne Sveen; Goriely, Stephane; Larsen, Ann-Cecilie; Görgen, Andreas; Hagen, Trine Wiborg & Renstrøm, Therese [Show all 12 contributors for this article] (2019). Indirect(n,γ)91,92Zr Cross SectionMeasurements for the s-Process. In Formicola, Alba; Junker, Matthias; Gialanella, Lucio & Imbriani, Gianluca (Ed.), Nuclei in the Cosmos XV. Springer. ISSN 978-3-030-13875-2. p. 359–362. doi: 10.1007/978-3-030-13876-9_65.
• Brits, C.P.; Malatji, Kgashane L.; Wiedeking, M.; Kheswa, BV; Goriely, S. & Bello Garrote, Frank Leonel [Show all 26 contributors for this article] (2019). Nuclear level densities and γ-ray strength functions of 180,181,182Ta. Physical Review C. ISSN 2469-9985. 99(5). doi: 10.1103/PhysRevC.99.054330. Full text in Research Archive
• Zeiser, Fabio; Tveten, Gry Merete; Potel, Gregory; Larsen, Ann-Cecilie; Guttormsen, Magne Sveen & Laplace, Thibault A. [Show all 22 contributors for this article] (2019). Restricted spin-range correction in the Oslo method: The example of nuclear level density and γ-ray strength function from 239Pu(d, pγ) 240Pu. Physical Review C. ISSN 2469-9985. 100:024305(2), p. 1–9. doi: 10.1103/PhysRevC.100.024305. Full text in Research Archive
• Lyons, Stephanie; Spyrou, Artemis; Liddick, Sean N.; Naqvi, Farheen; Crider, Benjamin P. & Dombos, Alexander C. [Show all 25 contributors for this article] (2019). 69,71Co β-decay strength distributions from total absorption spectroscopy. Physical Review C. ISSN 2469-9985. 100(2), p. 1–10. doi: 10.1103/PhysRevC.100.025806. Full text in Research Archive
• Liddick, Sean N.; Larsen, Ann-Cecilie; Guttormsen, Magne Sveen; Spyrou, Artemis; Crider, Benjamin P. & Naqvi, Farheen [Show all 29 contributors for this article] (2019). Benchmarking the extraction of statistical neutron capture cross sections on short-lived nuclei for applications using the β-Oslo method . Physical Review C. ISSN 2469-9985. 100:024624(2), p. 1–12. doi: 10.1103/PhysRevC.100.024624. Full text in Research Archive
• Goriely, Stéphane; Dimitriou, Paraskevi; Wiedeking, Mathis; Belgya, Támas; Firestone, Ryan & Kopecky, Jiri [Show all 19 contributors for this article] (2019). Reference database for photon strength functions. European Physical Journal A. ISSN 1434-6001. 55:172(10), p. 1–52. doi: 10.1140/epja/i2019-12840-1.
• Grigalavicius, Mantas; Mastrangelopoulou, Maria; Berg, Kristian; Arous, Delmon; Ménard, Mathilde & Henriksen-Raabe, Tine Therese [Show all 12 contributors for this article] (2019). Proton-dynamic therapy following photosensitiser activation by accelerated protons demonstrated through fluorescence and singlet oxygen production. Nature Communications. ISSN 2041-1723. 10(1). doi: 10.1038/s41467-019-12042-7. Full text in Research Archive
• Kullmann, Ina Kristine Berentsen; Larsen, Ann-Cecilie; Renstrøm, Therese; Beckmann, Kristine Sønstevold; Bello Garrote, Frank Leonel & Crespo Campo, Lucia [Show all 13 contributors for this article] (2019). First experimental constraint on the 191Os(n,γ) reaction rate relevant to s-process nucleosynthesis . Physical Review C. ISSN 2469-9985. 99(6). doi: 10.1103/PhysRevC.99.065806. Full text in Research Archive Show summary

  The nuclear level density and γ -decay strength of 192 Os have been extracted using particle- γ coincidence data from the 192 Os ( α , α ′ γ ) 192 Os reaction by means of the Oslo method. The level density is found to be a rather smooth function of excitation energy, approximately following the constant temperature model. The γ -decay strength is compared to photoneutron cross-section data above the neutron separation energy, and to E 1 and M 1 strengths for nuclei in this mass region derived from primary transitions following neutron capture. Our results are in good agreement with these previous data and draw a consistent picture of the γ -strength function in the range E γ ≈ 1.5 – 6 MeV . Using the measured nuclear level density and γ -decay strength as input to the nuclear-reaction code talys, we provide the first experimentally constrained Maxwellian-averaged cross section (MACS) for the 191 Os ( n , γ ) 192 Os reaction relevant to s -process nucleosynthesis. The systematic uncertainties introduced by the normalization procedure of the level density and γ -strength function were investigated and propagated to the calculated Maxwellian-averaged cross section. The obtained result of the Maxwellian-averaged cross section at k B T = 30 keV , ⟨ σ ⟩ n , γ = 1134 ± 375 mb , is in very good agreement with the theoretical estimate provided by the KADoNiS project, giving experimental support to the adopted KADoNiS value. Good agreement is also found with MACS values obtained from other libraries, such as TENDL-2017, ENDF/B-VII.0, and JEFF.

• Malatji, Kgashane Leroy; Wiedeking, Mathis; Goriely, Stephane; Brits, Christiaan Petrus; Kheswa, Bonginkosi Vincent & Bello Garrote, Frank Leonel [Show all 21 contributors for this article] (2019). Re-estimation of 180Ta nucleosynthesis in light of newly constrained reaction rates. Physics Letters B. ISSN 0370-2693. 791, p. 403–408. doi: 10.1016/j.physletb.2019.03.013. Full text in Research Archive
• Lewis, Rebecca; Liddick, Sean N.; Larsen, Ann-Cecilie; Spyrou, Artemis; Bleuel, Darren L. & Couture, Aaron J. [Show all 17 contributors for this article] (2019). Experimental constraints on the 73Zn(n,γ)74Zn reaction rate. Physical Review C. ISSN 2469-9985. 99(3). doi: 10.1103/PhysRevC.99.034601. Full text in Research Archive
• Dimitriou, Paraskevi; Belgya, Tamas; Cho, Yong-Sik; Filipescu, Daniela; Firestone, R & Goriely, Stéphane [Show all 17 contributors for this article] (2018). Developing reliable reaction gamma-ray data. The European Physical Journal Conferences. ISSN 2101-6275. 178, p. 1–3. doi: 10.1051/epjconf/201817806005. Full text in Research Archive
• Wilson, Joshua N.; Lebois, Matthieu; Qi, Liqiang; Amador-Celdran, Pedro; Bleuel, Darren L. & Briz, José A. [Show all 49 contributors for this article] (2018). Studies of fission fragment yields via high-resolution γ-ray spectroscopy. The European Physical Journal Conferences. ISSN 2101-6275. 169, p. 1–8. doi: 10.1051/epjconf/201816900030. Full text in Research Archive
• Larsen, Ann-Cecilie; Midtbø, Jørgen E.; Guttormsen, Magne Sveen; Renstrøm, Therese; Liddick, Sean N. & Spyrou, Artemis [Show all 22 contributors for this article] (2018). Enhanced low-energy γ-decay strength of 70Ni and its robustness within the shell model. Physical Review C. ISSN 2469-9985. 97(5), p. 1–9. doi: 10.1103/PhysRevC.97.054329. Full text in Research Archive
• Singh, Purnima; Korten, Wolfram; Hagen, Trine Wiborg; Görgen, Andreas; Grente, Lucie & Salsac, Marie Delphine [Show all 37 contributors for this article] (2018). Evidence for coexisting shapes through lifetime measurements in 98Zr. Physical Review Letters. ISSN 0031-9007. 121(19). doi: 10.1103/PhysRevLett.121.192501. Full text in Research Archive
• Bello Garrote, Frank Leonel; Görgen, Andreas; Mihai, C.; Abraham, T.; Crespo Campo, Lucia & Delaroche, Jean Paul [Show all 34 contributors for this article] (2018). Lifetime measurements in 138Nd. Physical Review C. ISSN 2469-9985. 97(6), p. 1–7. doi: 10.1103/PhysRevC.97.064310. Full text in Research Archive
• Hagen, Trine Wiborg; Görgen, Andreas; Korten, Wolfram; Grente, Lucie; Salsac, Marie Delphine & Farget, F. [Show all 27 contributors for this article] (2018). Lifetimes of excited states in triaxially deformed 107Tc and 109,111,113Rh. European Physical Journal A. ISSN 1434-6001. 54, p. 1–11. doi: 10.1140/epja/i2018-12482-9.
• Jones, M.D.; Macchiavelli, Augusto Oswaldo; Wiedeking, Mathis; Bernstein, Lee A.; Crawford, Heather L. & Campbell, C.M. [Show all 30 contributors for this article] (2018). Examination of the Low-Energy Enhancement of the gamma-ray Strength Function of 56Fe. Physical Review C. ISSN 2469-9985. 97(2). doi: 10.1103/PhysRevC.97.024327. Full text in Research Archive
• Crespo Campo, Lucia; Guttormsen, Magne Sveen; Bello Garrote, Frank Leonel; Eriksen, Tomas Kvalheim; Giacoppo, Francesca & Görgen, Andreas [Show all 15 contributors for this article] (2018). Test of the generalized Brink-Axel hypothesis in 64,65Ni. Physical Review C. ISSN 2469-9985. 98, p. 054303-1–054303-10. doi: 10.1103/PhysRevC.98.054303. Full text in Research Archive Show summary

  Previously published particle-γ coincidence data on the 64Ni(p,p′γ)64Ni and 64Ni(d,pγ)65Ni reactions were further analyzed to study the statistical properties of γ decay in 64,65Ni. To do so, the γ decay to the quasicontinuum region and discrete low-lying states was investigated at γ-ray energies of 2.0–9.6 and 1.6–6.1 MeV in 64 Ni and 65 Ni, respectively. In particular, the dependence of the γ -strength function with initial and final excitation energy was studied to test the validity of the generalized Brink-Axel hypothesis. Finally, the role of fluctuations in transition strengths was estimated as a function of γ-ray and excitation energy. The γ -strength function is consistent with the hypothesis of the independence of initial excitation energy, in accordance with the generalized Brink-Axel hypothesis. The results show that the γ decay to low-lying levels displays large fluctuations for low initial excitation energies.

• Renstrøm, Therese; Utsunomiya, H.; Nyhus, Hilde-Therese; Larsen, Ann-Cecilie; Guttormsen, Magne Sveen & Tveten, Gry Merete [Show all 16 contributors for this article] (2018). Verification of detailed balance for γ absorption and emission in Dy isotopes. Physical Review C. ISSN 2469-9985. 98(5), p. 1–14. doi: 10.1103/PhysRevC.98.054310. Full text in Research Archive Show summary

  The photoneutron cross sections of 162,163Dy have been measured for the first time in an energy region from the neutron threshold (Sn) up to ≈13MeV. The (γ,n) reaction was induced with quasimonochromatic laser Compton-scattered γ rays, produced at the NewSUBARU laboratory. The corresponding γ -ray strength functions (γ SF) have been calculated from the photoneutron cross sections. The data are compared to reanalyzed γSFs of 160–164Dy, which are measured below Sn. The excellent agreement with the photoneutron data at Sn confirms the principle of detailed balance. Thus, a complete γ SF is established covering in total the energy regionof1 Eγ 13MeV.Thesemid-shellwell-deformeddysprosiumisotopesallshowscissorsresonances with very similar structures. We find that our data predict the same integrated scissors strength as (γ,γ′) data when integrated over the same energy range, which shows that the scissors mode very likely is consistent with the generalized Brink hypothesis. Finally, using the γSFs as input in the reaction code TALYS, we have deduced radiative neutron-capture cross sections and compared them to direct measurements. We find a very good agreement within the uncertainties, which gives further support to the experimentally determined γ SFs.

• Utsunomiya, Hiroaki; Renstrøm, Therese; Tveten, Gry Merete; Goriely, Stéphane; Katayama, Seitaro & Ari-Izumi, Takashi [Show all 22 contributors for this article] (2018). Photoneutron cross sections for Ni isotopes: Toward understanding (n, γ ) cross sections relevant to weak s-process nucleosynthesis. Physical Review C. ISSN 2469-9985. 98(5), p. 1–9. doi: 10.1103/PhysRevC.98.054619. Full text in Research Archive Show summary

  Photoneutron cross sections were measured for 58Ni, 60Ni, 61Ni, and 64Ni at energies between the one-neutron and two-neutron thresholds using quasimonochromatic γ -ray beams produced in laser Compton scattering at the NewSUBARU synchrotron radiation facility. These photoneutron data are used to extract the γ -ray strength function above the neutron threshold, complementing the information obtained by the Oslo method below the threshold. We discuss radiative neutron-capture cross sections and the Maxwellian-averaged cross sections for Ni isotopes including 63Ni, a branching point nucleus along the weak s-process path. The cross sections are calculated with the experimentally constrained γ-ray strength functions from the Hartree-Fock-Bogolyubov plus quasiparticle–random-phase approximation based on the Gogny D1M interaction for both E1 and M1 components and supplemented with the M1 upbend.

• Utsunomiya, Hiroaki; Renstrøm, Therese; Tveten, Gry Merete; Gheorghe, Ioana; Filipescu, Dan Mihai & Belyshev, Sergey [Show all 22 contributors for this article] (2018). Photoneutron Reaction Data for Nuclear Physics and Astrophysics. The European Physical Journal Conferences. ISSN 2101-6275. 178. doi: 10.1051/epjconf/201817806003. Full text in Research Archive
• Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Midtbø, Jørgen E.; Crespo Campo, Lucia; Görgen, Andreas & Ingeberg, Vetle Wegner [Show all 11 contributors for this article] (2018). Gamma-widths, lifetimes and fluctuations in the nuclear quasi-continuum. The European Physical Journal Conferences. ISSN 2101-6275. 178(06001). doi: 10.1051/epjconf/201817806001. Full text in Research Archive
• Wiedeking, Mathis; Bernstein, Lee A.; Bleuel, Darren L.; Brits, Christiaan Petrus; Sowazi, Khanyisa & Görgen, Andreas [Show all 16 contributors for this article] (2017). Statistical gamma-ray decay studies at iThemba LABS. The European Physical Journal Conferences. ISSN 2101-6275. 146:05006, p. 1–4. doi: 10.1051/epjconf/201714605006.
• Hagen, Trine Wiborg; Görgen, Andreas; Korten, W.; Grente, L; Salsac, MD & Farget, F [Show all 28 contributors for this article] (2017). Evolution of nuclear shapes in odd-mass yttrium and niobium isotopes from lifetime measurements following fission reactions. Physical Review C. ISSN 2469-9985. 95(3). doi: 10.1103/PhysRevC.95.034302.
• Brits, C.P.; Wiedeking, M.; Bello Garrote, Frank Leonel; Bleuel, D. L.; Giacoppo, F. & Görgen, Andreas [Show all 21 contributors for this article] (2017). Resonances in odd-odd 182Ta. The European Physical Journal Conferences. ISSN 2101-6275. 146. doi: 10.1051/epjconf/201714605012. Full text in Research Archive
• Malatji, Kgashane L.; Kheswa, Bonginkosi Vincent; Wiedeking, M.; Bello Garrote, Frank Leonel; Brits, C.P. & Bleuel, D. L. [Show all 20 contributors for this article] (2017). Nuclear level densities and γ-ray strength functions of 180,181Ta and neutron capture cross sections. The European Physical Journal Conferences. ISSN 2101-6275. 146. doi: 10.1051/epjconf/201714601010. Full text in Research Archive
• Larsen, Ann-Cecilie; Spyrou, Artemis; Liddick, Sean N.; Guttormsen, Magne Sveen; Ingeberg, Vetle Wegner & Siem, Sunniva [Show all 25 contributors for this article] (2017). Novel Techniques for Constraining Neutron-capture Rates relevant to Heavy-element Nucleosynthesis. Proceedings of Science (PoS). ISSN 1824-8039. INPC2016. doi: 10.22323/1.281.0360. Full text in Research Archive
• Tveten, Gry Merete; Spyrou, Artemis; Schwengner, Ronald; Naqvi, Farheen; Larsen, Ann-Cecilie & Renstrøm, Therese [Show all 22 contributors for this article] (2017). The Statistical Properties Of 92Mo And Implications For The p-process. Proceedings of Science (PoS). ISSN 1824-8039. INPC2016. Full text in Research Archive Show summary

  A particularly challenging part of the question of how elements heavier than iron are created in extreme, astrophysical environments is the creation of the so-called p-nuclei, which are believed to be mainly produced in the O-Ne layer of type II supernovae or type Ia supernovae. The lack of needed nuclear data presents an obstacle in nailing down the precise site and astrophysical conditions for the production of these isotopes. Astrophysical model calculations are able to reproduce abundance patterns of most p-isotopes reasonably well, with some pivotal exceptions. In particular, p-isotopes of mass 92 ≤ A ≤ 98 are underproduced in calculations compared to the actual abundance of these isotopes. The p-isotope 92Mo represents one of the most severe cases of underproduction. State-of-the-art p-process calculations systematically underestimate the observed solar abundance of this isotope. The main destruction mechanism of this isotope in the standard description of the p-process is through the 92Mo(γ, p)91Nb reaction. Measurements on the nuclear level density and average gamma strength function of 92Mo have been carried out at the Oslo Cyclotron Laboratory. TALYS cross section and reaction rate calculations where the experimental results are used as input will be presented. The data provide stringent constraints on the 91Nb(p, γ)92Mo (and consequently the inverse) reaction rate. The reaction rate extracted in this work was used in reaction network calculations for the scenario of a p-process taking place in a type II supernova explosion as the shock front passes through the O-Ne layer of a 25 solar mass star.

• Crespo Campo, Lucia; Larsen, Ann-Cecilie; Bello Garrote, Frank Leonel; Eriksen, Tomas Kvalheim; Giacoppo, Francesca & Görgen, Andreas [Show all 13 contributors for this article] (2017). Investigating the gamma decay of Ni 65 from particle-gamma coincidence data. Physical Review C. ISSN 2469-9985. 96(1). doi: 10.1103/PhysRevC.96.014312. Full text in Research Archive
• Rose, Sunniva Johanne; Zeiser, Fabio; Wilson, JN; Oberstedt, A; Oberstedt, S & Siem, Sunniva [Show all 24 contributors for this article] (2017). Energy dependence of the prompt gamma-ray emission from the (d,p)-induced fission of U-234 and Pu-240. Physical Review C. ISSN 2469-9985. 96(1). doi: 10.1103/PhysRevC.96.014601. Full text in Research Archive
• Guttormsen, Magne Sveen; Goriely, Stephan; Larsen, Ann-Cecilie; Görgen, Andreas; Hagen, Trine Wiborg & Renstrøm, Therese [Show all 12 contributors for this article] (2017). Quasicontinuum γ decay of 91,92Zr: Benchmarking indirect (n,γ ) cross section measurements for the s process. Physical Review C. ISSN 2469-9985. 96(2). doi: 10.1103/PhysRevC.96.024313. Full text in Research Archive
• Wilson, JN; Lebois, M; Qi, L; Amador-Celdran, P; Bleuel, D & Briz, JA [Show all 48 contributors for this article] (2017). Production and study of neutron-rich nuclei using the licorne directional neutron source. Acta Physica Polonica B. ISSN 0587-4254. 48(3), p. 395–401. doi: 10.5506/APhysPolB.48.395. Full text in Research Archive
• Wilson, JN; Lebois, M; Qi, L; Amador-Celdran, P; Bleuel, D & Briz, JA [Show all 49 contributors for this article] (2017). Anomalies in the Charge Yields of Fission Fragments from the U (n,f) 238 Reaction. Physical Review Letters. ISSN 0031-9007. 118(22). doi: 10.1103/PhysRevLett.118.222501. Full text in Research Archive
• Spyrou, Artemis; Larsen, Ann-Cecilie; Liddick, Sean N.; Naqvi, Farheen; Crider, Benjamin P. & Dombos, Alexander C. [Show all 19 contributors for this article] (2017). Neutron-capture rates for explosive nucleosynthesis: the case of 68Ni(n, γ)69Ni. Journal of Physics G: Nuclear and Particle Physics. ISSN 0954-3899. 44. doi: 10.1088/1361-6471/aa5ae7. Full text in Research Archive
• Kheswa, Bonginkosi Vincent; Wiedeking, Mathis; Brown, Joshua A.; Larsen, Ann-Cecilie; Goriely, Stéphane & Guttormsen, Magne Sveen [Show all 24 contributors for this article] (2017). 137,138,139La(n,γ) cross sections constrained with statistical decay properties of 138,139,140La nuclei. Physical Review C. ISSN 2469-9985. 95(4). doi: 10.1103/PhysRevC.95.045805. Full text in Research Archive
• Larsen, Ann-Cecilie; Guttormsen, Magne Sveen; Blasi, Nives; Bracco, Angela; Camera, Franco & Crespo Campo, Lucia [Show all 23 contributors for this article] (2017). Low-energy enhancement and fluctuations of γ-ray strength functions in 56,57Fe: test of the Brink–Axel hypothesis. Journal of Physics G: Nuclear and Particle Physics. ISSN 0954-3899. 44(6). doi: 10.1088/1361-6471/aa644a. Full text in Research Archive
• Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Görgen, Andreas; Renstrøm, Therese; Siem, Sunniva & Tornyi, Tamas Gabor [Show all 7 contributors for this article] (2016). Is the generalized Brink-Axel hypothesis valid? Proceedings of Science (PoS). ISSN 1824-8039. 2016-September, p. 1–8. doi: 10.22323/1.281.0062. Full text in Research Archive
• Larsen, Ann-Cecilie; Spyrou, Artemisia; Liddick, Sean N.; Guttormsen, Magne Sveen; Ingeberg, Vetle Wegner & Siem, Sunniva [Show all 25 contributors for this article] (2016). Novel techniques for constraining neutron-capture rates relevant to heavy-element nucleosynthesis. Proceedings of Science (PoS). ISSN 1824-8039. 2016-September:360, p. 1–9. Full text in Research Archive
• Tveten, Gry Merete; Spyrou, Artemis; Schwengner, Ronald; Naqvi, Farheen; Larsen, Ann-Cecilie & Renstrøm, Therese [Show all 22 contributors for this article] (2016). The statistical properties of 92Mo and implications for the p-process. Proceedings of Science (PoS). ISSN 1824-8039. 2016-September:163.
• Bleuel, Darren L.; Bernstein, Lee A.; Brand, Christopher A; Cassata, William S; Daub, Brian H & Dauffy, Lucile S [Show all 16 contributors for this article] (2016). Method for detection of nuclear-plasma interactions in a 134Xe-doped exploding pusher at the national ignition facility. Plasma and Fusion Research. ISSN 1880-6821. 11(2). doi: 10.1585/pfr.11.3401075.
• Clement, E; Zielinska, Magdalena; Péru, Sophie; Goutte, Héloïse; Hilaire, Stephane & Görgen, Andreas [Show all 51 contributors for this article] (2016). Low-energy Coulomb excitation of 96,98Sr beams. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94(5). doi: 10.1103/PhysRevC.94.054326. Full text in Research Archive
• Crespo Campo, Lucia; Bello Garrote, Frank Leonel; Eriksen, Tomas Kvalheim; Görgen, Andreas; Guttormsen, Magne Sveen & Hadynska-Klek, Katarzyna [Show all 14 contributors for this article] (2016). Statistical γ -decay properties of Ni 64 and deduced (n,γ) cross section of the s -process branch-point nucleus Ni 63. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94(4). doi: 10.1103/PhysRevC.94.044321. Full text in Research Archive
• Ay, K.o.; Ozgur, Mustafa; Algin, Emel; Guttormsen, Magne Sveen; Bello Garrote, Frank Leonel & Crespo Campo, Lucia [Show all 19 contributors for this article] (2016). Nuclear level densities and gamma-ray strength functions of 145,149,151Nd isotopes. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 766(012027). doi: 10.1088/1742-6596/766/1/012027.
• Krzysiek, M; Kmiecik, M; Maj, A; Bednarczyk, P; Bracco, A & Crespi, FCL [Show all 56 contributors for this article] (2016). Pygmy dipole resonance in Ce 140 via inelastic scattering of O 17. Physical Review C. Nuclear Physics. ISSN 0556-2813. 93(4). doi: 10.1103/PhysRevC.93.044330.
• Negi, D; Wiedeking, M; Lanza, EG; Litvinova, E; Vitturi, A & Bark, RA [Show all 35 contributors for this article] (2016). Nature of low-lying electric dipole resonance excitations in Ge 74. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94(2). doi: 10.1103/PhysRevC.94.024332. Full text in Research Archive
• Hagen, Trine Wiborg; Grente, L; Görgen, Andreas; Salsac, MD; Korten, W & Farget, F [Show all 29 contributors for this article] (2016). Lifetime measurments of excited states in neutron-rich fission fragments. Acta Physica Polonica B. ISSN 0587-4254. 47(3), p. 903–910. doi: 10.5506/APhysPolB.47.903.
• Ducasse, Q; Jurado, B; Aiche, M; Marini, P; Mathieu, L & Görgen, Andreas [Show all 28 contributors for this article] (2016). Investigation of the U 238 (d,p) surrogate reaction via the simultaneous measurement of γ -decay and fission probabilities. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94(2). doi: 10.1103/PhysRevC.94.024614. Full text in Research Archive
• Tveten, Gry Merete; Spyrou, A; Schwengner, R; Naqvi, F; Larsen, Ann-Cecilie & Eriksen, Tomas Kvalheim [Show all 22 contributors for this article] (2016). Completing the nuclear reaction puzzle of the nucleosynthesis of Mo 92. Physical Review C. Nuclear Physics. ISSN 0556-2813. 94(2). doi: 10.1103/PhysRevC.94.025804. Full text in Research Archive
• Marini, P.; Ducasse, Q; Jurado, B; Aiche, M; Mathieu, L & Barreau, G. [Show all 33 contributors for this article] (2016). First simultaneous measurement of fission and gamma probabilities of <sup>237</sup>U and <sup>239</sup>Np via surrogate reactions. The European Physical Journal Conferences. ISSN 2101-6275. 122. doi: 10.1051/epjconf/201612212004.
• Ratkiewicz, A.; Berzak Hopkins, L.; Bleuel, D. L.; Bernstein, L. A.; van Bibber, K & Cassata, W. S. [Show all 11 contributors for this article] (2016). A recoverable gas-cell diagnostic for the National Ignition Facility. Review of Scientific Instruments. ISSN 0034-6748. 87(11). doi: 10.1063/1.4961278.

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• Paulsen, Wanja; Li, Kevin Ching Wei; Siem, Sunniva; Ingeberg, Vetle Wegner; Larsen, Ann-Cecilie & Eriksen, Tomas Kvalheim [Show all 20 contributors for this article] (2023). Remeasuring the gamma-decay branching ratio of the Hoyle state.
• Grigalavicius, Mantas; Mastrangelopoulou, Maria; Berg, K.; Arous, Delmon; Ménard, M. & Raabe-Henriksen, T. [Show all 12 contributors for this article] (2021). Publisher Correction: Proton-dynamic therapy following photosensitiser activation by accelerated protons demonstrated through fluorescence and singlet oxygen production (Nature Communications, (2019), 10, 1, (3986), 10.1038/s41467-019-12042-7). Nature Communications. ISSN 2041-1723. 12(1). doi: 10.1038/s41467-021-27175-x.
• Paulsen, Wanja; Görgen, Andreas; Siem, Sunniva & Li, Kevin Ching Wei (2021). Studies of shape coexistence in 140Sm. Show summary

  The shape of atomic nuclei can vary vastly, several shapes can even coexist within the same nucleus in certain regions of the nuclear chart. Shape coexistence is believed to be present at higher excitation energies in the N=78 isotones 140Sm and 142Gd [1], where the nucleus of interest is 140Sm in this case. 140Sm has previously been studied in a coulomb excitation experiment performed by M. Klintefjord et. al. [2] at REX-ISOLDE where results showed considerable gamma-softness and the resulting level scheme follows the theoretical prediction of a triaxial nucleus [3], but further investigation is needed to conclude. A new coulomb experiment on 140Sm has been performed using HIE-ISOLDE, yielding data of incredible quality which has also let us vastly improve the level scheme of this nucleus. Preliminary results from this dataset will be presented as well as a deeper look into gamma-softness as well as the possibility of 140Sm having shape coexistence. [1] W. Starzecki et al., Phys. Lett. B 200, 419 (1988). [2] M. Klintefjord et al. Phys. Rev. C 93, 054303 (2016) [3] F. Iachello, Phys. Rev. Lett. 85, 3580 (2000)

• Paulsen, Wanja; Siem, Sunniva & Görgen, Andreas (2020). Assessment of the radiative width of the Hoyle state.
• Ingeberg, Vetle Wegner; Siem, Sunniva; Wiedeking, M.; Abrahams, Kenzo John; Arnswald, K. & Bello Garrote, Frank Leonel [Show all 36 contributors for this article] (2019). Inverse-Oslo Method – a tool for expanding our understanding of the r-process.
• Edin, Nina Frederike J; Rykkelid, Anne Marit; Görgen, Andreas; Baker, Agnes; Siem, Sunniva & Ytre-Hauge, Kristian [Show all 7 contributors for this article] (2019). Very high yield of double strand breaks found at the distal end of the proton Bragg peak. Radiotherapy and Oncology. ISSN 0167-8140. 133, p. 594–594.
• Rykkelid, Anne Marit; Tormodsrud, Vera; Siem, Sunniva; Görgen, Andreas; Ytre-Hauge, Kristian & Malinen, Eirik [Show all 7 contributors for this article] (2019). Very high RBE values found at the distal end of the proton Bragg peak.
• Rykkelid, Anne Marit; Siem, Sunniva; Ytre-Hauge, Kristian; Malinen, Eirik & Edin, Nina Frederike J (2018). Very high relative biological effectiveness found at the distal end of the proton Bragg peak. Radiotherapy and Oncology. ISSN 0167-8140. 127, p. 1259–1259.
• Guttormsen, Magne Sveen; Larsen, Ann-Cecilie; Midtbø, Jørgen E.; Crespo Campo, Lucia; Görgen, Andreas & Ingeberg, Vetle Wegner [Show all 11 contributors for this article] (2017). Gamma-widths, lifetimes and fluctuations in the nuclear quasi-continuum.
• Rykkelid, Anne Marit; Siem, Sunniva; Görgen, Andreas; Ytre-Hauge, Kristian; Brondz, Efim & Sandvik, Joe Alexander [Show all 9 contributors for this article] (2017). A high-resolution proton irradiator for in vitro studies of relative biological effectiveness.
• Tveten, Gry Merete; Spyrou, Artemis; Schwengner, Ronald; Naqvi, Farheen; Larsen, Ann-Cecilie & Eriksen, Tomas Kvalheim [Show all 22 contributors for this article] (2016). The Statistical Properties Of 92Mo And Implications For The p-process. Show summary

  A particularly challenging part of the question of how elements heavier than iron are created in extreme, astrophysical environments is the creation of the so-called p-nuclei, which are believed to be mainly produced in the O-Ne layer of type II supernovae or type Ia supernovae. The lack of needed nuclear data presents an obstacle in nailing down the precise site and astrophysical conditions for the production of these isotopes. Astrophysical model calculations are able to reproduce abundance patterns of most p-isotopes reasonably well, with some pivotal exceptions. In particular, p-isotopes of mass 92 ≤ A ≤ 98 are underproduced in calculations compared to the actual abundance of these isotopes. The p-isotope 92Mo represents one of the most severe cases of underproduction. State-of-the-art p-process calculations systematically underestimate the observed solar abundance of this isotope. The main destruction mechanism of this isotope in the standard description of the p-process is through the 92Mo(γ, p)91Nb reaction. Measurements on the nuclear level density and average gamma strength function of 92Mo have been carried out at the Oslo Cyclotron Laboratory. TALYS cross section and reaction rate calculations where the experimental results are used as input will be presented. The data provide stringent constraints on the 91Nb(p, γ)92Mo (and consequently the inverse) reaction rate. The reaction rate extracted in this work was used in reaction network calculations for the scenario of a p-process taking place in a type II supernova explosion as the shock front passes through the O-Ne layer of a 25 solar mass star.

• Hasanbegovic, Amir; Siem, Sunniva; Søråsen, Oddvar & Aunet, Snorre (2017). Exploring the SEU Dependence on Supply Voltage scaling in 90 nm and 65 nm CMOS Flip-flops. Universitetet i Oslo. Full text in Research Archive

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