Reports de recercahttp://hdl.handle.net/2117/1846852024-03-29T13:20:16Z2024-03-29T13:20:16ZCalibration of Parameters to Model Liquid Pb-17Li Alloy: Lennard-Jones Interatomic PotentialsAl Awad, Abdulrahmanhttp://hdl.handle.net/2117/3608092022-01-26T19:10:50Z2022-01-26T19:01:13ZCalibration of Parameters to Model Liquid Pb-17Li Alloy: Lennard-Jones Interatomic Potentials
Al Awad, Abdulrahman
Progress report regarding the PhD project. Internal document, for the resrearch group at UPC only.
2022-01-26T19:01:13ZAl Awad, AbdulrahmanMeasurement of the 235U(n,f) cross section relative to the 6Li(n,t) and 10B(n,a) standards from thermal to 170 keV neutron energy range at n_TOFAmaducci, SimoneCosentino, LuigiBarbagallo, MassimoCalviño Tavares, FranciscoCasanovas Hoste, AdriàTarifeño Saldivia, Ariel EstebanCortés Rossell, Guillem Perehttp://hdl.handle.net/2117/1664432024-03-10T08:14:43Z2019-07-19T07:38:45ZMeasurement of the 235U(n,f) cross section relative to the 6Li(n,t) and 10B(n,a) standards from thermal to 170 keV neutron energy range at n_TOF
Amaducci, Simone; Cosentino, Luigi; Barbagallo, Massimo; Calviño Tavares, Francisco; Casanovas Hoste, Adrià; Tarifeño Saldivia, Ariel Esteban; Cortés Rossell, Guillem Pere
The 235U(n,f) cross section was measured in a wide energy range at n_TOF relative to 6Li(n,t) and 10B(n,alpha), with high resolution and in a wide energy range, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. This allowed us to make a direct comparison of the reaction yields under the same experimental conditions, and taking into account the forward/backward emission asymmetry. A hint of an anomaly in the 10÷30 keV neutron energy range had been previously observed in other experiments, indicating a cross section systematically lower by several percent relative to major evaluations. The present results indicate that the evaluated cross section in the 9÷18 keV neutron energy range is indeed overestimated, both in the recent updates of ENDF/B-VIII.0 and of the IAEA reference data. Furthermore, these new high-resolution data confirm the existence of resonance-like structures in the keV neutron energy region. The new, high accuracy results here reported may lead to a reduction of the uncertainty in the 1÷100 keV neutron energy region. Finally, the present data provide additional confidence on the recently re-evaluated cross section integral between 7.8 and 11 eV.
2019-07-19T07:38:45ZAmaducci, SimoneCosentino, LuigiBarbagallo, MassimoCalviño Tavares, FranciscoCasanovas Hoste, AdriàTarifeño Saldivia, Ariel EstebanCortés Rossell, Guillem PereThe 235U(n,f) cross section was measured in a wide energy range at n_TOF relative to 6Li(n,t) and 10B(n,alpha), with high resolution and in a wide energy range, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. This allowed us to make a direct comparison of the reaction yields under the same experimental conditions, and taking into account the forward/backward emission asymmetry. A hint of an anomaly in the 10÷30 keV neutron energy range had been previously observed in other experiments, indicating a cross section systematically lower by several percent relative to major evaluations. The present results indicate that the evaluated cross section in the 9÷18 keV neutron energy range is indeed overestimated, both in the recent updates of ENDF/B-VIII.0 and of the IAEA reference data. Furthermore, these new high-resolution data confirm the existence of resonance-like structures in the keV neutron energy region. The new, high accuracy results here reported may lead to a reduction of the uncertainty in the 1÷100 keV neutron energy region. Finally, the present data provide additional confidence on the recently re-evaluated cross section integral between 7.8 and 11 eV.Neutron capture on ^{205}Tl: depicting the abundance pattern of lead isotopes in s-process nucleosynthesisCasanovas Hoste, AdriàTarifeño Saldivia, Ariel EstebanDomingo-Pardo, CCalviño Tavares, Franciscohttp://hdl.handle.net/2117/1660172024-03-10T08:20:28Z2019-07-11T10:34:21ZNeutron capture on ^{205}Tl: depicting the abundance pattern of lead isotopes in s-process nucleosynthesis
Casanovas Hoste, Adrià; Tarifeño Saldivia, Ariel Esteban; Domingo-Pardo, C; Calviño Tavares, Francisco
We propose to use the TOF technique to measure the neutron capture cross section of 205Tl(n,gamma) over the full energy range of stellar interest. An accurate measurement of this cross section is needed for a complete and consistent understanding of the s-process nucleosynthesis of the heaviest nuclei which are produced in low-mass and low metallicity AGB-stars. The only previous TOF measurement has yield only a partial information, insufficient for a reliable analysis of the complex branching pattern around 205Pb and 205Tl. Furthermore, there is also a discrepancy of 40% between the two previous activation measurements made at kT=24 keV. The cross section of 205Tl(n,gamma) is particularly relevant because it affects the equilibrium that is established in some stellar conditions between the 205Tl -> 205Pb bound-state Beta-decay and the 205Pb -> 205Tl E.C. decay. This effect induces a complex interplay which influences the final s-process abundance of both nuclei. We propose to measure accurately and with high resolution the 205Tl(n,gamma) cross section by using a set of four C6D6 detectors in combination with the pulsed neutron-source of CERN n_TOF.
Proposal: Neutron capture on 205Tl: depicting the abundance pattern of lead isotopes in s-process nucleosynthesis
2019-07-11T10:34:21ZCasanovas Hoste, AdriàTarifeño Saldivia, Ariel EstebanDomingo-Pardo, CCalviño Tavares, FranciscoWe propose to use the TOF technique to measure the neutron capture cross section of 205Tl(n,gamma) over the full energy range of stellar interest. An accurate measurement of this cross section is needed for a complete and consistent understanding of the s-process nucleosynthesis of the heaviest nuclei which are produced in low-mass and low metallicity AGB-stars. The only previous TOF measurement has yield only a partial information, insufficient for a reliable analysis of the complex branching pattern around 205Pb and 205Tl. Furthermore, there is also a discrepancy of 40% between the two previous activation measurements made at kT=24 keV. The cross section of 205Tl(n,gamma) is particularly relevant because it affects the equilibrium that is established in some stellar conditions between the 205Tl -> 205Pb bound-state Beta-decay and the 205Pb -> 205Tl E.C. decay. This effect induces a complex interplay which influences the final s-process abundance of both nuclei. We propose to measure accurately and with high resolution the 205Tl(n,gamma) cross section by using a set of four C6D6 detectors in combination with the pulsed neutron-source of CERN n_TOF.