Ponencias (Física Atómica, Molecular y Nuclear)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10866

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Neutron capture and total cross-section measurements on Mo-94'95'96 at n_TOF and GELINA
(EDP Sciences, 2023-05) Mucciola, R.; Paradela, Carlos; Manna, A.; Alaerts, Gery; Massimi, C.; Kopecky, S.; Mengoni, A.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Comunidad Europea de Energía Atómica (Euratom)
Capture and total cross section measurements for 94'95'96 MO have been performed at the neutron time -of-flight facilities, n_TOF at CERN and GELINA at JRC-Geel. The measurements were performed using isotopically enriched samples with an enrichment above 95% for each of the (94'95'96)M0 isotopes. The capture measurements were performed at n_TOF using C6D6 detectors and a new sTED detector. The transmission measurements were performed at a 10 m station of GELINA using a Li-6 glass neutron detector. Preliminary results of these measurements are presented.
Multi-channel experimental and theoretical approach to study the 12C(18O,18F)12B single charge exchange reaction
(IOP Publishing Ltd., 2023) Spatafora, A.; Carbone, D.; Cappuzzello, F.; Cavallaro, Manuela; Acosta, L.; Agodi, Clementina; Amador-Valenzuela, Paulina; Lay Valera, José Antonio; Zagatto, Vinicius A. B.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Research Council (ERC)
The broad network of nuclear reactions populated in the 18O + 12C collision was studied to test the capability of state-of-art nuclear structure and reaction theories to describe both the direct and sequential components of the (18O, 18F) single charge exchange nuclear reaction. The experiment was performed using the 18O beam at 275 MeV incident energy produced by the K800 superconducting cyclotron and the MAGNEX magnetic spectrometer at the Laboratori Nazionali del Sud of the Istituto Nazionale di Fisica Nucleare. A unique comprehensive and coherent theoretical calculation, able to describe the whole network of direct reactions, is the approach proposed for the first time to analyse this large set of experimental data. This holistic approach, applied both to the experimental and theoretical analysis, is the main feature and novelty of the work here presented.
Measurement of the U-235(n,f) cross section relative to the (10) B( n a) reaction with Micromegas detectors at the CERN n_TOF facility: first results
(EDP Sciences, 2023-05) Michalopoulou, V.; Diakaki, M.; Vlastou, R.; Kokkoris, M.; Stamatopoulos, A.; Tsinganis, Andrea; Eleme, Z.; Patronis, N.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE)
Neutron cross section measurements are often made relative to a neutron cross section standard. Thus, the accuracy of the neutron standards determines the best possible accuracy of the neutron measurements. The U-235(n,f) cross section is widely used as reference, while it is considered a standard at thermal point and between 0.15 to 200 MeV. For this reason, additional cross section data for the U-235(n,f) reaction are useful in order to improve the accuracy and to extend the energy range of the standard. In this work, preliminary results of the measurement of the 235U(n,f) cross-section relative to the standard (10) B(n,a) reaction are presented. The high accuracy measurement was performed at the experimental area EAR-1 of the n_TOF facility at CERN, aiming at covering the energy range from the thermal region up to approximately 100 keV. The samples were produced at JRC-Geel in Belgium, while the experimental setup was based on Micromegas detectors.
Measurement of the Gd-160(n, gamma) cross section at n_TOF and its medical implications
(EDP Sciences, 2023-05) Mastromarco, Mario; Manna, A.; García Infantes, F.; Amaducci, Simone; Mengoni, A.; Massimi, C.; Tagliente, G.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
Neutron -capture reactions on gadolinium isotopes play an important role in several fields of physics, in particular in nuclear Astrophysics for the understanding of the nucleosynthesis of heavy elements (beyond iron) in stars via the s- and r-processes [1] and in nuclear technology. Another important application of gadolinium is linked to the production of terbium, that offers a set of clinically interesting isotopes for theranostics, characterized by complementary physical decay characteristics. In particular, the low -energy beta(-) emitter terbium-161 is very similar to lutetium-177 in terms of half-life (6.89 d), beta(-) - energy and chemical properties. Being a significant emitter of conversion/Auger electrons, greater therapeutic effect can therefore be expected in comparison to Lu-177 [2, 3]. For this reason, in the last decade, the study of the neutron capture reaction Gd-160(n,,gamma)(161) Gd and the subsequent beta(-) - decay in terbium-161 is getting particular attention. As the nuclear data on the Gd-160 neutron capture reaction are quite scarce and inconsistent, a new measurement of the capture cross section of Gd-160 at the CERN neutron Time -Of-Flight facilty was performed in order to provide high resolution, high -accuracy data on this important reaction, in the energy range from thermal to hundreds of keV. In this contribution, the preliminary results of the n_TOF measurement are presented.
High resolution Se-80(n,gamma) cross section measurement at CERN n_TOF
(EDP Sciences, 2023-05) Babiano Suárez, V.; Balibrea Correa, J.; Caballero-Ontanaya, L.; Domingo Pardo, César; Ladarescu, I.; Lerendegui Marco, Jorge; Cortés Giraldo, Miguel Antonio; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICIN). España
Neutron capture cross section measurements of isotopes close to s -process branching -points are of fundamental importance for the understanding of this nucleosynthesis mechanism through which about 50% of the elements heavier than iron are produced. We present in this contribution the results corresponding to the high resolution measurement, for first time ever, of the 80Se(n, y) cross section, in which 98 resonances never measured before have been reported. As a consequence, ten times more precise values for the MACS have been obtained compared to previous accepted value adopted in the astrophysical KADoNiS data base.
First measurement of the Nb-94(n,gamma) cross section at the CERN n_TOF facility
(EDP Sciences, 2023-03) Balibrea Correa, J.; Babiano Suárez, V.; Lerendegui Marco, Jorge; Domingo Pardo, César; Ladarescu, I.; Tarifeno Saldivia, A.; Alcayne, V.; Guerrero Sánchez, Carlos; Cortés Giraldo, Miguel Antonio; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICIN). España; Consejo Superior de Investigaciones Científicas (CSIC)
One of the crucial ingredients for the improvement of stellar models is the accurate knowledge of neutron capture cross-sections for the different isotopes involved in the s-,r- and i- processes. These measurements can shed light on existing discrepancies between observed and predicted isotopic abundances and help to constrain the physical conditions where these reactions take place along different stages of stellar evolution. In the particular case of the radioactive Nb-94, the Nb-94(n,gamma) cross-section could play a role in the determination of the s-process production of Mo-94 in AGB stars, which presently cannot be reproduced by state-of-the-art stellar models. There are no previous Nb-94(n,gamma) experimental data for the resolved and unresolved resonance regions mainly due to the difficulties in producing high-quality samples and also due to limitations in conventional detection systems commonly used in time-of-flight experiments. Motivated by this situation, a first measurement of the Nb-94(n,gamma) reaction was carried out at CERN n_TOF, thereby exploiting the high luminosity of the EAR2 area in combination with a new detection system of small-volume C6D6-detectors and a high quality Nb-94-sample. The latter was based on hyper-pure Nb-93 material activated at the high-flux reactor of ILL-Grenoble. An innovative ring-configuration detection system in close geometry around the capture sample allowed us to significantly enhance the signal-to-background ratio. This set-up was supplemented with two conventional C6D6 detectors and a high-resolution LaCl3(Ce)-detector, which will be employed for addressing reliably systematic effects and uncertainties. At the current status of the data analysis, 18 resonance in Nb-94+n have been observed for the first time in the neutron energy range from thermal up to 10 keV.
First high resolution measurement of neutron capture resonances in Yb-176 at the n TOF CERN facility
(EDP Sciences, 2023-05) García Infantes, F.; Praena, Julia; Casanovas, A.; Mastromarco, Mario; Aberle, Oliver; Alcayne, V.; Altieri, S.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
Several international agencies recommend the study of new routes and new facilities for producing radioisotopes with application to nuclear medicine. Lu-177 is a versatile radioisotope used for therapy and diagnosis (theranostics) of cancer with good success in neuroendocrine tumours that is being studied to be applied to a wider range of tumours. Lu-177 is produced in few nuclear reactors mainly by the neutron capture on Lu-176. However, it could be produced at high -intensity accelerator-based neutron facilities. The energy of the neutrons in accelerator-based neutron facilities is higher than in thermal reactors. Thus, experimental data on the Yb-176(n,(sic)) cross-section in the eV and keV region are mandatory to calculate accurately the production of Yb-177, which beta decays to 177Lu. At present, there are not experimental data available from thermal to 3 keV of the Yb-176(n,(sic)) cross-section. In addition, there is no data in the resolved resonance region (RRR). This contribution shows the first results of the Yb-176 capture measurement performed at the n_TOF facility at CERN.
Detector set up for the measurements of the neutron -induced fission cross section of U-235 relative to n -p scattering up to 150 MeV at CERN-n_TOF
(EDP Sciences, 2023-05) Pirovano, E.; Manna, A.; Colonna, Nicola; Camprini, P. C.; Cosentino, Luigi; Dietz, M.; Ducasse, Q.; Finocchiaro, Paolo; Massimi, C.; Cortés Giraldo, Miguel Antonio; Lerendegui Marco, Jorge; Guerrero Sánchez, Carlos; Quesada Molina, José Manuel; Zugec, P.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
A new measurement of the U-235(n,f) fission cross section was carried out at n_TOF. The experiment covered the neutron energy range from 10 MeV up to 500 MeV, and it used the H-1(n,n) cross section as normalization for the neutron fluence measurement. In this contribution, the measurements and the characterization of the detectors covering the incident energy range up to 150 MeV are discussed.
Compton imaging for enhanced sensitivity (n,gamma) cross section TOF experiments: Status and prospects
(EDP Sciences, 2023) Domingo Pardo, César; Babiano Suárez, V.; Balibrea Correa, J.; Caballero, L.; Ladarescul, I.; Lerendegui Marco, Jorge; Tarifeno Saldivia, A.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICIN). España; Consejo Superior de Investigaciones Científicas (CSIC)
Radiative neutron-capture cross sections are of pivotal importance in many fields such as nucle-osynthesis studies or innovative reactor technologies. A large number of isotopes have been measured with high accuracy, but there are still a large number of relevant isotopes whose cross sections could not be experimentally determined yet, at least with sufficient accuracy and completeness, owing to limitations in detection techniques, sample production methods or in the facilities themselves. In the context of the HYMNS (High-sensitivitY Measurements of key stellar Nucleo-Synthesis reactions) project over the last six years we have developed a novel detection technique aimed at background suppression in radiative neutron-capture time-of-flight measurements. This new technique utilizes a complex detection set-up based on position-sensitive radiation-detectors deployed in a Compton-camera array configuration. The latter enables to implement gamma-ray imaging techniques, which help to disentangle true capture events arising from the sample under study and contaminant background events from the surroundings. A summary on the main developments is given in this contribution together with an update on recent experiments at CERN n_TOF and an outlook on future steps.
Characterization of a detector setup for the measurement of the U-235(n,f) cross section relative to n -p scattering up to 500 MeV at the n_TOF facility at CERN
(EDP Sciences, 2023-05) Manna, A.; Pirovano, E.; Colonna, Nicola; Castelluccio, D.; Camprini, P. C.; Cosentino, Luigi; Dietz, M.; Ducasse, Q.; Cortés Giraldo, Miguel Antonio; Lerendegui Marco, Jorge; Quesada Molina, José Manuel; Zugec, P.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
The measurement of the U-235(n,f) reaction cross section in the neutron energy region 10 MeV to 500 MeV was carried out at the CERN n_TOF facility. The experimental campaign, completed in 2018, provided precise and accurate data on the fission reaction relative to neutron -proton elastic scattering. A description and characterization of the used setup for the simultaneous measurement of fission fragments and neutron flux is reported here.
Characterisation of the n_TOF 20 m beam line at CERN with the new spallation target
(EDP Sciences, 2023) Pavón Rodríguez, J. A.; Alcayne, V.; Amaducci, Simone; Bacak, M.; Casanovas, A.; Cortés Giraldo, Miguel Antonio; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
The n_TOF facility hosts CERN's pulsed neutron source, comprising two beam lines of different flight paths and one activation station. It is based on a proton beam delivered by the PS accelerator impinging on a lead spallation target. During Long Shutdown 2 (LS2) at CERN (2019-2021), a major upgrade of the spallation target was carried out in order to optimize the performances of the neutron beam. Therefore, the characteristics of n_TOF two experimental areas were investigated in detail. In this work, the focus is on the second experimental area (EAR2), located 20 m above the spallation target. Preliminary results of the neutron energy distribution and beam line energy resolution are presented, compared to previous experimental campaigns and Monte Carlo simulations with the FLUKA code. Moreover, preliminary results of the spatial beam profile measurements are shown.
The NUMEN project: probing nuclear response to weak interaction by nuclear reactions
(IOP Publishing Ltd, 2023) Carbone, D.; Agodi, Clementina; Bellone, J. I.; Burrello, S.; Calabrese, S.; Cappuzzello, F.; Cavallaro, Manuela; Lay Valera, José Antonio; Zagatto, Vinicius A. B.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Research Council (ERC)
Different reactions channels induced by the 18O + 40Ca collisions at 275 MeV incident energy are simultaneously measured and analysed consistently within the same reaction and structure frameworks within the NUMEN project. The project aims to provide data-driven information for the determination of the nuclear matrix elements involved in the neutrinoless double beta decay. In particular, the elastic and inelastic scattering, one- and two-proton transfer, one-neutron transfer, and single charge exchange reactions are explored. The full quantum-mechanical calculations, performed by including microscopic nuclear structure inputs, describe well all the experimental data, giving support to a multi-channel strategy for the analysis of heavy-ion induced direct reactions.
The neutron time-of-flight facility n TOF at CERN: Recent facility upgrades and detector developments
(IOP Publishing Ltd, 2023) Domingo Pardo, C.; Aberle, Oliver; Alcayne, V.; Altieri, S.; Amaducci, Simone; Andrzejewski, J.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE); Ministerio de Ciencia e Innovación (MICIN). España
Based on an idea by Carlo Rubbia, the n TOF facility at CERN has been operating for over 20 years. It is a neutron spallation source, driven by the 20 GeV/c proton beam from the CERN PS accelerator. Neutrons in a very wide energy range (from GeV, down to sub-eV kinetic energy) are generated by a massive Lead spallation target feeding two experimental areas. EAR1, horizonal with respect to the proton beam direction is set at 185 meters from the spallation target. EAR2, on the vertical line from the spallation source, is placed at 20 m. Neutron energies for experiments are selected by the time-of-flight technique (hence the name n TOF), while the long flight paths ensure a very good energy resolution. Over one hundred experiments have been performed by the n TOF Collaboration at CERN, with applications ranging from nuclear astrophysics (synthesis of the heavy elements in stars, big bang nucleosynthesis, nuclear cosmo-chronology), to advanced nuclear technologies (nuclear data for applications, nuclear safety), as well as for basic nuclear science (reaction mechanisms, structure and decay of highly excited compound states). During the planned shutdown of the CERN accelerator complex between 2019 and 2021, the facility went through a substantial upgrade with a new target-moderator assembly, refurbishing of the neutron beam lines and experimental areas. An additional measuring and irradiation station (the NEAR Station) has been envisaged and its capabilities for performing material test studies and new physics opportunities are presently explored. An overview of the facility and of the activities performed at CERN is presented in this contribution, with a particular emphasis on the most relevant experiments for nuclear astrophysics.
Proton halo effects in the 8B+64Zn collision around the Coulomb barrier
(IOP Publishing Ltd, 2023) Di Pietro, Alessia; Spartá, R.; Figuera, Pierpaolo; Tengblad, Olof; Moro Muñoz, Antonio Matías; Lei, J.; Fernández García, Juan Pablo; Vignales, S.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE)
The 8B+64Zn reaction at 38.5 MeV has been studied at HIE-ISOLDE CERN to investigate proton halo effect on the reaction dynamics. For the first time it was used the only existing post-accelerated 8B beam. The measured elastic scattering angular distribution showed a small suppression of the Coulomb-nuclear interference peak, opposite to what observed for the one-neutron halo nucleus 11Be on the same target where a large suppression was observed instead. Inclusive angular and energy distributions of breakup fragments were also measured showing that, both, elastic and non-elastic breakup contribute. The presence of the additional Coulomb interactions halo-core and halo-target in 8B makes the reaction dynamics in this proton-halo nucleus different than the neutron-halo case.
Overview of the dissemination of n_TOF experimental data and resonance parameters
(EDP Sciences, 2023) Dupont, E.; Otuka, Naohiko; Rochman, D.; Noguere, G.; Aberle, Oliver; Alcayne, V.; Altieri, S.; Cortés Giraldo, Miguel Antonio; Guerrero Sánchez, Carlos; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
The n_TOF neutron time-of-flight facility at CERN is used for nuclear data measurements. The n_TOF Collaboration works closely with the Nuclear Reaction Data Centres (NRDC) network to disseminate the experimental data through the international EXFOR library. In addition, the Collaboration helps integrate the results in the evaluated library projects. The present contribution describes the dissemination status of n_TOF results, their impact on evaluated libraries and ongoing efforts to provide n_TOF resonance parameters in ENDF-6 format for further use by evaluation projects.
New perspectives for neutron capture measurements in the upgraded CERN-n_TOF Facility
(E D P Sciences, 2023) Lerendegui Marco, Jorge; Casanovas, A.; Alcayne, V.; Aberle, Oliver; Altieri, S.; Amaducci, Simone; Andrzejewski, J.; Cortés Giraldo, Miguel Antonio; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE)
The n_TOF facility has just undergone in 2021 a major upgrade with the installation of its third generation spallation target that has been designed to optimize the performance of the two n_TOF time-of-flight lines. This contribution describes the key features and limitations for capture measurements in the two beam lines prior to the target upgrade and presents first results of (n,gamma) measurements carried out as part of the commissioning of the upgraded facility. In particular, the energy resolution, a key factor for both increasing the signal-to background ratio and obtaining accurate resonance parameters, has been clearly improved for the 20 m long vertical beam-line with the new target design while keeping the remarkably high resolution of the long beamline n_TOF-EAR1. The improvements in the n_TOF neutron beam-lines need to be accompanied by improvements in the instrumentation. A review is given on recent detector R&D projects aimed at tackling the existing challenges and further improving the capabilities of this facility.
New high intensity Heavy - Ion beams @ INFN-LNS: NUMEN project status and perspective
(IOP Publishing Ltd, 2023) Agodi, Clementina; Cappuzzello, F.; Acosta, L.; Amador-Valenzuela, Paulina; Auerbach, Naftali; Avanzi, L. H.; Bellone, J. I.; Bijker, R.; Lay Valera, José Antonio; Zagatto, Vinicius A. B.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
The upgrade project POTLNS to produce high-intensity beams has already started at INFN- Laboratori Nazionali del Sud in Catania (Italy). The POTLNS project was triggered by the NUMEN physics case that aims to provide experimental information on the Nuclear Matrix Elements (NMEs) that enter in the expression of the neutrino-less double beta (0νββ) decay half-life. The tools proposed by NUMEN project are the cross-section measurements of nuclear Double Charge Exchange (DCE) reactions. The search for 0νββ decay is currently a key topic in physics, due to its possible wide implications for nuclear physics, particle physics and cosmology: the NUMEN project could provide a crucial contribution in this search.
New detection systems for an enhanced sensitivity in key stellar (n,gamma) measurements
(E D P Sciences, 2023) Lerendegui Marco, Jorge; Babiano Suárez, V.; Balibrea Correa, J.; Domingo Pardo, César; Ladarescu, I.; Tarifeno Saldivia, A.; Alcayne, V.; Cano-Ott, D.; González-Romero, E.; Martínez, T.; Mendoza, E.; Guerrero, C.; Cortés Giraldo, Miguel Antonio; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE); Ministerio de Ciencia e Innovación (MICIN). España; Consejo Superior de Investigaciones Científicas (CSIC)
Neutron capture cross-section measurements are fundamental in the study of astrophysical phenomena, such as the slow neutron capture (s-) process of nucleosynthesis operating in red-giant and massive stars. However, neutron capture measurements via the time-of-flight (TOF) technique on key s-process nuclei are often challenging. Difficulties arise from the limited mass (similar to mg) available and the high sample-related background in the case of the unstable s-process branching points. Measurements on neutron magic nuclei, that act as s-process bottlenecks, are affected by low (n,gamma) cross sections and a dominant neutron scattering background. Overcoming these experimental challenges requires the combination of facilities with high instantaneous flux, such as n_TOF-EAR2, with detection systems with an enhanced detection sensitivity and high counting rate capabilities. This contribution reviews some of the latest detector developments in detection systems for (n,gamma) measurements at n_TOF, such as i-TED, an innovative detection system which exploits the Compton imaging technique to reduce the dominant neutron scattering background and s-TED, a highly segmented total energy detector intended for high flux facilities. The discussion will be illustrated with results of the first measurement of key the s-process branching-point reaction Se-79(n,gamma).
Neutron-induced cross section measurements
(EPJ Web of Conferences, 2023) Massimi, C.; Aberle, Oliver; Alcayne, V.; Altieri, S.; Amaducci, Simone; Andrzejewski, J.; Cortés Giraldo, Miguel Antonio; Pérez Maroto, Pablo; Quesada Molina, José Manuel; Zugec, P.; n_TOF Collaboration (Autoría grupal); Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
Neutron-induced cross sections represent the main nuclear input to models of stellar and Big-Bang nucleosynthesis. While (n, gamma) reactions are relevant for the formation of elements heavier than iron, (n,p) and (n,alpha) reactions can play an important role in specific cases. The time-of-flight method is routinely used at n_TOF to experimentally determine the cross section data. In addition, recent upgrades of the facility will allow the use of activation techniques as well, possibly opening the way to a systematic study of neutron interaction with radioactive isotopes. In the last 20 years n_TOF has provided a large amount of experimental data for Nuclear Astrophysics. Our plan is to carry on challenging measurements and produce nuclear data in the next decades as well.
Impact of ICRF fast-ions on core turbulence and MHD activity in ASDEX upgrade
(AIP Conference Proceedings, 2023-08-18) Bilato, A.; Angioni, C.; Bañón Navarro, A.; Bobkov, V.; Bosman, T.; Di Siena, A.; Fable, E.; Galdón Quiroga, Joaquín; Hidalgo Salaverri, Javier; Rueda Rueda, José; Weiland, M.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España; EUROfusion Consortium
Experiments in various tokamaks and their analysis identify the fast ions (FI) generated by NBI and/or ICRF heating as one of the main causes of the observed improvement in core confinement: fast ions can reduce core microturbulence (mainly Ion-Temperature-Gradient (ITG) driven modes) either electrostatically or electromagnetically, or they can resonate with fishbones and high-frequency Alfvén modes, which in turn contribute in stabilizing ITG. In this perspective, we discuss recent experiments done on ASDEX Upgrade (AUG) where ICRF is the main actuator for FI generation for energies above 100 keV. Additionally, ICRF-FIs can substantially impact the MHD activity and its consequent effects on fast ion losses (FILs) and ion-cyclotron emission (ICE). We present dedicated AUG experiments with NBI-D further accelerated by ICRF.

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