n_TOF Collaboration(Calviani, M. et al), Domingo-Pardo, C., & Tain, J. L. (2011). Fission Cross-section Measurements of (233)U, (245)Cm and (241,243)Am at CERN n_TOF Facility. J. Korean Phys. Soc., 59(2), 1912–1915.
Abstract: Neutron-induced fission cross-sections of minor actinides have been measured using the nTOF white neutron source at CERN. Geneva, as part of a large experimental program aiming at collecting new data relevant for nuclear astrophysics and for the design of advanced reactor systems. The measurements at nTOF take advantage of the innovative features of the n_TOF facility, namely the wide energy range, high instantaneous neutron flux and good energy resolution. Final results on the fission cross-section of (233)U, (245)cm and (243)Am from thermal to 20 MeV are here reported, together with preliminary results for (241)Am. The measurement have been performed with a dedicated Fast Ionization Chamber (FIC), a fission fragment detector with a very high efficiency, relative to the very well known cross-section of (235)U, measured simultaneously with the same detector.
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Mollaebrahimi, A. et al: A., S. (2025). First observation of MNT isotope beams at the FRS Ion Catcher. Nucl. Phys. A, 1057, 123041–4pp.
Abstract: An exploratory experiment on Multi-Nucleon Transfer (MNT) reactions was successfully conducted at the FRS Ion Catcher setup at GSI. The experiment demonstrated the production of MNT-driven radioactive ion beams (RIBs) produced by decelerated relativistic beams. A beam of 238U ions was reacted with a 209Bi target at near-Coulomb barrier energies inside the specially modified Cryogenic Stopping Cell (CSC) for the production and thermalization of MNT products. These products were then identified using a Multiple-Reflection Time-Of-Flight Mass Spectrometer (MRTOF-MS). The observation of target-like MNT fragments along the A = 211 isobaric chain provided a proof-of-principle for future MNT studies with the FRS Ion Catcher setup.
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Lerendegui-Marco, J., Hallam, J., Cisterna, G., Sanchis-Molto, A., Balibrea-Correa, J., Babiano-Suarez, V., et al. (2025). First experimental results and optimization study of the portable neutron-gamma imager GN-Vision. Appl. Radiat. Isot., 224, 111826–13pp.
Abstract: GN-Vision is a compact, dual-modality imaging device designed to simultaneously localize the spatial origin of y-ray and slow neutron sources, with potential applications in nuclear safety, security, and hadron therapy. The system utilizes two position-sensitive detection planes, combining Compton imaging techniques for yray visualization with passive collimation for imaging slow and thermal neutrons (energies below 100 eV). This paper presents the first experimental outcomes from the initial GN-Vision prototype, focused on the development of its neutron imaging capabilities. Following this experimental assessment, we explore the device's performance potential and discuss several Monte Carlo simulation-based optimizations aimed at refining the neutron collimation system. These optimizations seek to improve real-time imaging efficiency and cost-effectiveness, enhancing GN-Vision's applicability for future practical deployments.
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Ralet, D. et al, Gadea, A., & Perez, R. M. (2019). Evidence of octupole-phonons at high spin in Pb-207<bold> </bold>. Phys. Lett. B, 797, 134797–6pp.
Abstract: A lifetime measurement of the 19/2(-) state in Pb-207 has been performed using the Recoil Distance Doppler-Shift (RDDS) method. The nuclei of interest were produced in multi-nucleon transfer reactions induced by a Pb-208 beam impinging on a Mo-100 enriched target. The beam-like nuclei were detected<bold> </bold>and identified in terms of their atomic mass number in the VAMOS++ spectrometer while the prompt gamma rays were detected by the AGATA tracking array. The measured large reduced transition probability B(E3, 19/2(-) -> 13/2(+)) = 40(8) W.u. is the first indication of the octupole phonon at high spin in Pb-207. An analysis in terms of a particle-octupole-vibration coupling model indicates that the measured B(E3) value in Pb-207 is compatible with the contributions from single-phonon and single particle E3 as well as E3 strength arising from the double-octupole-phonon 6(+) state, all adding coherently. A crucial aspect of the coupling model, namely the strong mixing between single-hole and the phonon-hole states, is confirmed in a realistic shell-model calculation.
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Sahin, E. et al, & Algora, A. (2024). Collectivity at the prolate-oblate transition: The 21+ lifetime of 190W. Phys. Lett. B, 857, 138976–8pp.
Abstract: The neutron-rich rare isotope W-190 is discussed as a candidate for a prolate-oblate transitional nucleus with maximum gamma-softness. The collectivity of this isotope is assessed for the first time by the measurement of the reduced E2 transition probability of its first 2(+) state to the ground state. The experiment employed the FAst TIming Array (FATIMA), comprised of 36 LaBr3(Ce) scintillators, which was part of the DESPEC setup at GSI, Darmstadt. The 4(1)(+) and 2(1)(+) states of W-190 were populated subsequently to the decay of its 127(12) μs isomeric J(pi )= 10(-) state. The mean lifetime of the 2(1)(+) state was determined to be tau = 274(28) ps, which corresponds to a B(E2; 2(1)(+ )-> 0(1)(+)) value of 95(10) W.u. The results motivated a revision of previous calculations within an energy-density functional-based interacting boson model-2 approach, yielding E2 transition properties and spectroscopic quadrupole moments for tungsten isotopes. From comparison to theory, the new data suggest that W-190 is at the transition from prolate to oblate structure along the W isotopic chain, which had previously been discussed as a nuclear shape-phase transition.
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