Ponencias (Física Atómica, Molecular y Nuclear)

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

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Mostrando 1 - 20 de 184

A Preamplifier for the Front-End Readout System of Particles Tracking in Secondary Electron Detectors
(Institute of Electrical and Electronics Engineers (IEEE), 2012-08-20) Garzón Camacho, Alejandro; Fernández Martínez, Begoña; González Álvarez, Marcos Aurelio; Ceballos Cáceres, Joaquín Francisco; Rosa Utrera, José Manuel de la; Física Atómica, Molecular y Nuclear; Electrónica y Electromagnetismo; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
This paper presents the design and characterization of a preamplifier used in the electronic front-end of low-pressure gaseous secondary electron detectors. The circuit - implemented in a printed circuit board as a proof of concept - has been designed to cope with the specifications of the readout electronics used in spatial resolution measurements. Experimental results show a transimpedance gain of 80dB, an overall voltage gain of 18 dB, a peak signal-to-noise ratio of 36.5 dB and a shaping time frame of 140-170ns. These features improve the performance of previous reported approaches to the problem, and allow us to minimize the overlapping probability in secondary electron detections for radioactive ion beams tracking, achieving a counting rate higher than 106 particles per second.
Time-of-Flight Detector for the Characterisation of Laser-Accelerated Protons
(Institute of Electrical and Electronics Engineers (IEEE), 2014-06-12) Seimetz, M.; Bellido, P.; Soriano, A.; Huertas, C.; García López, Francisco Javier; Jiménez Ramos, María del Carmen; Fernández Martínez, Begoña; Conde, P.; Crespo, E.; Benlloch, J. M.; Física Atómica, Molecular y Nuclear; Física Aplicada II; Ministerio de Economía y Competitividad (MINECO). España; Agencia Estatal de Investigación. España; Generalitat Valenciana
Lasers of ultra-high intensity focused on thin targets can form plasmas and release large numbers of charged particles with kinetic energies in the MeV region. The characterization of the accelerated particles requires suitable detectors. We present a time-of-flight detector based on a plastic scintillator optimized for the spectral analysis of laser-accelerated protons.
Dosimetric Calibration of Radiochromic Film For Laser-accelerated Proton Beams
(Institute of Electrical and Electronics Engineers (IEEE), 2014-06-12) Bellido, P.; Seimetz, M.; Soriano, A.; Huertas, C.; García López, Francisco Javier; Jiménez Ramos, María del Carmen; Fernández Martínez, Begoña; Conde, P.; Crespo, E.; Benlloch, J. M.; Física Atómica, Molecular y Nuclear; Física Aplicada II; Agencia Estatal de Investigación. España; Generalitat Valenciana
When an ultra-intense and ultra-short laser pulse interacts with solid matter a fraction of the laser pulse can be converted into kinetic energy of a beam of charged particles. Radiochromic film (RCF), widely used as radiation detector in the field of conventional radiotherapy, can be used as detector for laser-accelerated protons. If used in stack configuration it is a useful and versatile tool to obtain 2D spatial distribution and energetic information of proton beams.
Neutron beam line for TOF measurements at the Spanish National Accelerator Lab (CNA)
(EDP Sciences, 2020-09-30) Macías, M.; Fernández Martínez, Begoña; Praena, J.; Física Atómica, Molecular y Nuclear; Ministerio de Economía y Competitividad (MINECO). España; Asociación Española Contra el Cáncer; Junta de Andalucía
A few years ago, the Spanish National Accelerator Lab (CNA) developed the first accelerator-based neutron facility in Spain called HiSPANoS (HiSPAlis Neutron Source). The first applications of the line were related to integral measurements applied to nuclear astrophysics, dosimetry and single event effects produced by neutrons in electronic devices. The successful of HiSPANoS pushed the enhancement of the facility. In collaboration with the NEC® Company, two devices were designed for pulsing ion beams (Chopper) and for compressing in time (Buncher) the pulsed beams. The Chopper-Buncher system has been already installed and commissioned. Proton and deuteron beams are delivered with repetition rates from 62.5 kHz to 2 MHz and 1 ns pulse width. In addition, a new line of the 3 MV Tandem Pelletron accelerator was designed for neutron time-of-flight (TOF) experiments. Conventional devices and a dedicated Pick-Up for timing measurements form the new line. In order to check the performance of the whole TOF system, we have carried out the measurement of the neutron spectrum produced by 7Li(p,n)7Be reaction at Ep = 1912 keV. Such spectrum has been measured by the TOF technique few times and it can be considered a standard neutron field, in particular in nuclear astrophysics. The first result of such experiment performed at CNA is shown in some detail. The excellent performance of the accelerator, the Chopper-Buncher system and the acquisition system allow us to offer the TOF line at HiSPANoS-CNA to the neutron community.
miniBELEN: a modular neutron counter for (α, n) reactions
(EDP Sciences, 2023-05-23) Mont-Geli, N.; Tarifeño-Saldivia, A.; Fraile, L. M.; Viñals, S.; Perea, A.; Pallás, M.; Fernández Martínez, Begoña; Gómez Camacho, Joaquín José; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Quesada Molina, José Manuel; Villamarín, D.; Física Atómica, Molecular y Nuclear; Ministerio de Economía y Competitividad (MINECO). España; Generalitat Valenciana; European Union (UE)
miniBELEN is a modular and transportable neutron moderated counter with a nearly flat neutron detection efficiency up to 10 MeV. Modularity implies that the moderator can be reassembled in different ways in order to obtain different types of response. The detector has been developed in the context of the Measurement of Alpha Neutron Yields (MANY) collaboration, which is a scientific effort aiming to carry out measurements of (𝛼, 𝑛) production yields, reaction cross-sections and neutron energy spectra. In this work we present and discuss several configurations of the miniBELEN detector. The experimental validation of the efficiency calculations using 252Cf sources and the measurement of the 27Al(𝛼, 𝑛) 30P reaction is also presented.
Theo4exp: a theory service for euro-labs community
(Jagellonian University, 2025-04) Rodríguez Gallardo, Manuela; Colò, G.; Dudek, J.; Dedes, I.; Gaamouci, A.; Muñoz Chimbo, Carla Tatiana; Moumene, I.; Física Atómica, Molecular y Nuclear; Ministerio de Economia, Industria y Competitividad (MINECO). España; Agencia Estatal de Investigación. España
A new virtual access facility Theo4Exp provides a variety of computer codes for nuclear structure and reactions, accessible to researchers worldwide. The use of these codes is made simple by the adoption of clear interfaces and the implementation of graphical tools. Results can be easily transmitted, exchanged and compared. The EURO-LABS project, funded within the EC Horizon Europe program, has provided the appropriate framework and dedicated personnel to create this service.
First 80Se(n,γ) cross section measurement with high resolution in the full stellar energy range 1 eV - 100 keV and its astrophysical implications for the s-process
(EPJ Web of Conferences, 2022-02-24) Babiano-Suarez, Victor; Balibrea-Correa, J.; Caballero-Ontanaya, L.; Domingo-Pardo, C.; Ladarescu, I.; Lerendegui Marco, Jorge; Guerrero Sánchez, Carlos; Cortés Giraldo, Miguel Antonio; Moreno-Soto, Javier; Quesada Molina, José Manuel; Ramos-Doval, D.; Física Atómica, Molecular y Nuclear; European Commission (EC); Ministerio de Ciencia. España
Most elements heavier than iron have been generated in the stellar media by means of neutron capture reactions, approximately half are produced by the slow neutron capture or s-process. Radiative neutron capture cross section measurements are of fundamental importance for the study of this mechanism. In this contribution we present a brief summary on the measurement and results for the 80Se(n,γ) cross-section. The experiment was carried out at CERN n_TOF EAR1 via the time of flight (ToF) technique, using four C6D6 scintillation detectors with very fast response. More than a hundred new resonances have been analyzed for the first time with a high accuracy. The MACS obtained at kT = 8 keV is 36% smaller than the recommended value in KADo-NiS. Some of the astrophysical implications of this result are elucidated in this contribution.
The n_TOF NEAR Station Commissioning and first physics case
(EPJ Web of Conferences, 2023-05-26) Stamati, M. E.; Torres Sánchez, P; Pérez Maroto, Pablo; Cecchetto, M; Goula, S; Mastromarco, Mario; Física Atómica, Molecular y Nuclear
The NEAR Station is a new experimental area developed at the n_TOF Facility at CERN. The activation station of NEAR underwent a characterization of the beam following the installation of the new n_TOF Spallation Target. The commissioning of the neutron beam comprises a set of simulations made with the FLUKA code and experimental verification. The experimental determination of the neutron spectrum was made using activation techniques with three separate set-ups. Two set-ups were based on the Multi-foil Activation technique (MAM-1 and MAM-2), and the third set-up relied on the process of neutron moderation and activation of a single material (ANTILoPE). The three set-ups are presented. Also the present plans and future perspectives of the activation station of NEAR are discussed.
Impact of core excitations in break-up reactions with halo nuclei
(EDP Sciences, 2023-12-08) Lay Valera, José Antonio; Punta de la Herrán, Pedro; Moro Muñoz, Antonio Matías; Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España
We revisit the resonant break-up of 19C on protons at intermediate energies. In this reaction, it was found, for the first time in a halo nucleus to our knowledge, that the cross section was largely dominated by the excitation of the core. In this contribution, we study the robustness of this conclusion against the choice of different optical potentials for the core.
The role of deformation in the 17C structure and its influence in transfer and breakup reactions
(EDP Sciences, 2023-12-08) Punta de la Herrán, Pedro; Lay Valera, José Antonio; Moro Muñoz, Antonio Matías; Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España
C structure is studied within a two-body model, a weakly bound neutron moving in a deformed potential generated by the core. A semi-microscopic method has been used to generate the deformed valencecore potential. The method consists of the convolution of a realistic nucleon-nucleon (NN) interaction with the core transition densities, which are obtained by antisymetrized molecular dynamics (AMD). The results highlight the important role of deformation for this nucleus and can be easily applied to reaction calculations.
At the edge of shape coexistence in the Z=40 region
(EPJ Web of Conferences, 2025-06-25) Maya-Barbecho, E.; Baid, Samira; Arias Carrasco, José Miguel; Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
In this contribution, the shape coexistence phenomenon near the proton sub-shell closure at Z=40 is analyzed. Particular emphasis is placed on extracting the nuclear deformation values by examining experimental B(E2) transition rates and observing how the kinematic moment of inertia evolves in these nuclei. Based on the analysis of these two observables, we arrive at the conclusion that the notable effects of shape coexistence at approximately Z=40 are largely diminished in Mo isotopes and are scarcely detectable in Ru isotopes.
Recent Highlights and Prospects on (n, γ) Measurements at the CERN n_TOF Facility
(EDP Sciences, 2025) Lerendegui Marco, Jorge; Alcayne, V.; Babiano Suárez, V.; Bacak, M.; Balibrea Correa, J.; Casanovas, A.; Domingo Pardo, C.; De La Fuente, G.; Gameiro, B.; García Infantes, F.; Cortés Giraldo, Miguel Antonio; Fernández Martínez, Begoña; Guerrero Sánchez, Carlos; Pérez Maroto, Pablo; Perkowski, J.; Física Atómica, Molecular y Nuclear; European Research Council (ERC); Ministerio de Ciencia e Innovación (MICIN). España; Consejo Superior de Investigaciones Científicas (CSIC); European Union (UE)
Neutron capture cross-section measurements are fundamental in the study of the slow neutron capture (s-) process of nucleosynthesis and for the development of innovative nuclear technologies. One of the best suited methods to measure radiative neutron capture (n,γ) cross sections over the full stellar range of interest for all the applications is the time-of-flight (TOF) technique. Overcoming the current experimental limitations for TOF measurements, in particular on low mass unstable samples, requires the combination of facilities with high instantaneous flux, such as the CERN n_TOF facility, with detection systems with an enhanced detection sensitivity and high counting rate capabilities. This contribution presents a summary about the recent highlights in the field of (n,γ) measurements at n_TOF. The recent upgrades in the facility and in new detector concepts for (n,γ) measurements are described. Last, an overview is given on the existing limitations and prospects for TOF measurements involving unstable targets and the outlook for activation measurements at the brand new high-flux n_TOF-NEAR station.
First in-beam tests on simultaneous PET and Compton imaging aimed at quasi-real-time range verification in hadron therapy
(EDP Sciences, 2022) Balibrea-Correa, Javier; Lerendegui-Marco, Jorge; Babiano-Suarez, Victor; Domingo-Pardo, César; Laderescu, Ion; Guerrero Sánchez, Carlos; Rodríguez González, María Teresa; Jiménez Ramos, María del Carmen; Fernández Martínez, Begoña; Física Aplicada II; Física Atómica, Molecular y Nuclear
Hadron therapy with protons has advantages with respect to conventional radiotherapy because of the maximization of the dose at the Bragg peak. As a drawback, and because of different systematic uncertainty sources, a quasi-real time monitoring for the proton range verification is required to reduce safety margins. In this respect, two gamma-ray imaging techniques are pursued: prompt gamma-ray monitoring and positron-annihilation tomography (PET). The promising prompt gamma-ray monitoring requires detection systems with large detection efficiency, high time resolution, compactness, fast response, low sensitivity to neutron-induced backgrounds and powerful image reconstruction capabilities. On the other hand, in-beam PET surveys require additionally good γ-ray position reconstruction resolution. In this contribution we show that, to a large extent, both approaches can be simultaneously accomplished by using an array of Compton cameras conveniently arranged around the target volume. Here we demonstrate experimentally the suitability of such an array, named i-TED, for PG monitoring in ion-range monitoring during Hadron Therapy, in-beam PET survey and β+ production yield measurements capability. Furthermore, with the use of GPUs, a quasi-real time PG monitoring and in-beam PET can be achieved.
Quantum Computing CFD Simulations: Review and State of the Art
(American Society of Thermal and Fluids Engineering, 2025-03-17) Malinverno, Giulio; Blasco Alberto, Javier; Lecumberri SanMartin, Jon; Lamata Manuel, Lucas; Física Atómica, Molecular y Nuclear
This article is meant to review and discuss the possible applications of Quantum computing in the area of computational fluid dynamics (CFD), with a focus on the application to the aerospace compact heat exchangers. Quantum computing is a type of computation that harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations. Several approaches have been proposed for the solutions of CFD problems with the use of quantum algorithms, being the rationale of the development the estimated scalability of quantum computing and the analogy between Navier Stokes equations with the hydrodynamic Schrödinger equation or between the Lattice Boltzmann equation with the quantum Dirac equation. A review of the current state-of-the-art of quantum computing applied to CFD will be carried out, with the description of some practical applications, highlining how the technology is promising but still in an early stage of development.
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); 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.; 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); 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); 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); 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); 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.

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