Artículos (Centro Nacional de Aceleradores)

URI permanente para esta colecciónhttps://hdl.handle.net/11441/10939

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The Lyon Mint in the Roman Tomares Hoard (Seville): Some Considerations on Its Metallic Composition Determined by XRF
(Willey, 2025-06-15) Pliego Vázquez, Ruth; Gómez-Tubio, Blanca María; Alcaide Ramírez, María; Scrivano, Simona; Respaldiza Galisteo, Miguel Ángel; Física Atómica, Molecular y Nuclear; Prehistoria y Arqueología; Física Aplicada III; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Universidad de Sevilla
COSMONAUT: A COmpact Spectrometer for Measurements of Neutrons at the ASDEX Upgrade Tokamak
(American Institute of Physics, 2024) Nocente, M.; Molin, A. D.; D Rigamonti, D.; Rosa, M. D.; Fernández Martínez, Begoña; Fugazza, S.; Guerrero Sánchez, Carlos; Gorini, G.; Kazakov, Y. O.; Tardini, G.; Tardocchi, M.; ASDEX Upgrade Team; Eurofus Tokamak Exploitat Team; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE); European Union (UE). H2020
A COmpact Spectrometer for Measurements Of Neutrons at the ASDEX Upgrade Tokamak (COSMONAUT) has been developed for spectroscopy measurements of the 2.45 MeV neutron emission from deuterium plasmas at the ASDEX Upgrade. The instrument is based on a CLYC-7 inorganic scintillator, whereby the detection of fusion neutrons occurs via their interaction with 35Cl nuclei in the detector crystal, leading to a peak in the detector response function and providing excellent neutron/gamma-ray discrimination capabilities. The diagnostics is installed along a radial line of sight and makes use of a digital system to record time resolved data for the whole duration of the discharge. Measurements in ASDEX Upgrade plasmas with neutral beam injection have been carried out and are successfully interpreted using state-of-the-art modeling codes. Next step applications of the diagnostics are in experiments aimed at generating energetic particles by ion cyclotron resonance heating schemes. In these scenarios, COSMONAUT will provide unique information on the acceleration of deuterons beyond the beam injection energy and on their confinement, for comparison with modeling.
Experimental study of 6He Coulomb breakup as an indirect measurement of 4He(2n,γ)6He reaction rate for the astrophysical r-process
(EDP Sciences, 2024-10-08) Godos, D.; Acosta, L.; Fernández García, Juan Pablo; O'Malley, P.; Sánchez Benítez, A. M.; Casal Berbel, Jesús; Gómez Camacho, Joaquín José; Arias Carrasco, José Miguel; Rodríguez Gallardo, Manuela; von Seeger, W.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; National Science Foundation (NSF). United States; Universidad Autónoma de México (UNAM); Consejo Nacional de Ciencia y Tecnología (CONACYT). México
In this work, we report the measurement of elastic and Coulomb break-up channels in 6He+208Pb collisions at Elab = 19.3 MeV, close to the Coulomb barrier of this system ∼ 19 MeV. In the context of the astrophysical r-process, the reaction 4He(2n,γ)6He has been proposed to be a key reaction in the path of synthesizing seed nuclei for the r-process, as 12C, in an environment composed mainly of alpha particles and neutrons. Based on a theoretical approach for treating three body reactions by means of which its reaction rate can be inferred, our experimental approach aims to obtain an indirect measurement of the reaction rate of 4He(2n,γ)6He by measuring the Coulomb breakup of 6He under the intense electric field produced by a 208Pb target nucleus. The experiment was carried out at the TriSol facility operated in the Nuclear Science Laboratory of the University of Notre Dame, USA, which delivered a 6He beam together with other contaminants. Particular care must be taken for the alpha particles produced in the production reaction.
Tuning the Er3+ Sensitization by Si Nanoparticles in Nanostructured as-grown Al2 O3 Films
(American Institute of Physics, 2009) Núez Sánchez, S.; Serna, R.; García López, Francisco Javier; Petford Long, A. K.; Tanase, M.; Kabius, B.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Comisión Interministerial de Ciencia y Tecnología (CICYT). España; European Union (UE); Electron Microscopy Center. Chicago
Nanostructured films consisting of single Si nanoparticles (NPs) and Er3+ ions layers separated by nanometer-scale Al2 O 3 layers of controlled thickness have been prepared in order to tune the energy transfer between Si NPs and Er3+ ions. The amorphous Si NPs with an effective diameter of ∼4.5 nm are formed during growth and are able to sensitize the Er3+ ions efficiently with no postannealing treatments. The characteristic distance for energy transfer from Si NPs to Er3+ ions in Al2 O3 is found to be in the 1 nm range. It is shown that in the nanostructured films, it is possible to achieve an optimized configuration in which almost all the Er3+ ions have the potential to be excited by the Si NPs. This result stresses the importance of controlling the dopant distribution at the nanoscale to achieve improved device performance.
Modular Apparatus for Nuclear Reactions Spectroscopy (MARS): Characterization and First Application to Determine 12C(6Li,4He)14Ng.s Nuclear Reaction Cross Sections
(Springer, 2025) Garrido Gómez, Laura; Vegas Díaz, Alejandro; González Álvarez, Marcos Aurelio; Fernández García, Juan Pablo; Fernández Martínez, Begoña; Ferrer Fernández, Francisco Javier; Lopez Aires, D.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Gobierno de España; Ministerio de Economía y Competitividad (MINECO). España; Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; National Science Foundation (NSF). United States
This work presents MARS (Modular apparatus for nuclear reactions spectroscopy) and its characterization prior to its first application to measure 6Li+12C nuclear reactions. Measurements were performed at the 3 MV tandem accelerator of the CNA (National Accelerator Center), in Seville, Spain. The 6Li projectiles were accelerated at energies around the 6Li+12C Coulomb barrier (Vcm B ∼ 3.0 MeV - center of mass and V lab B ∼ 4.5 MeV - laboratory frame). Using a 6Li2+ beam, we measured at 13 laboratory energies from 4.00 to 7.75 MeV. Thus, we present the excitation function of 12C(6Li,4He)14Ng.s. reaction, at 2 backward angles (110.0◦ and 140.0◦). The projectile dissociation, leading to this reaction, increases with the bombarding energies around the Coulomb barrier. This dissociation is favored at an optimum energy Eop b ≥ VB + |Qbu|, where VB is the Coulomb barrier of the system, and |Qbu| is the module of Q-value for the 6Li dissociation into 4He+2H. This result corroborates a systematic analysis of weakly bound projectiles reacting on several targets
Production and measurement of a stellar neutron spectrum at 30 keV
(Springer, 2024-10-06) Praena, Javier; Verdera, Antònia; García López, Javier; Martín Hernández, Guido; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Agencia Estatal de Investigación. España; European Commission (EC)
A few years ago, we theoretically studied the production of a stellar neutron spectrum at kT = 30 keV using a shaped proton beam impinging on a thick lithium target. Here, we first measure the proton distribution to better control the produced neutron spectrum. Then, we measure the forward-emitted angle-integrated neutron spectrum of the 7Li(p,n)7Be reaction via time-of-flight neutron spectrometry with such proton distribution. The result resembles a stellar neutron spectrum at kT = 30 keV. This method avoids in activation experiments the need for spectrum correction. In the case of spherical samples, no knowledge of the cross-section of the isotope being measured by activation would be necessary. Therefore, the present method is of interest for isotopes with unknown or poorly known cross-sections, such as branching points in astrophysics. The key point of our method is the experimental control of the proton distribution that impinges on the lithium target.
Tuning light emission in Bi and V codoped MgAl2O4 nanostructured films
(Elsevier, 2025-02-24) Gorni, G.; Serna, R.; García López, Francisco Javier; Gonzalo, J.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Agencia Estatal de Investigación. España; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); Consejo Superior de Investigaciones Científicas (CSIC); Ministerio de Ciencia e Innovación (MICIN). España; NextGeneration. U. E.
This study investigates the synthesis of novel Bi and V-codoped MgAl2O4 nanostructured thin films for near-white-light emission upon UV excitation. Sequential pulsed laser deposition (PLD) from Bi, V, and MgAl2O4 targets was employed to prepare nanostructured films with different compositions. The films have been thoroughly analyzed using Rutherford backscattering spectrometry (RBS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and photoluminescence spectroscopy (PL). Upon heat treatments at 500 °C and 800 °C, the films exhibit a broad blue emission in Bi-doped films and a broad yellow emission in V-doped films, respectively. We demonstrate that a strategic combination of Bi and V codoping in MgAl2O4 nanostructures results in near-white light emission. This study highlights the ability to finely control the nanostructure and emission properties of thin films using PLD, and the use of abundant and non-toxic elements to produce white light emission, with significant implications for advanced and sustainable photonic applications.
Characterization of New Silicon Carbide Neutron Detectors with Thermal and Fast Neutrons
(Elsevier, 2024) Pérez, Martín; Zamorano, Felipe; Fleta, Celeste; Fernández Martínez, Begoña; Guerrero Sánchez, Carlos; Godignon, Philippe; Pellegrini, Giulio; Pérez Maroto, Pablo; Guardiola, Consuelo; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE). H2022; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
The aim of this work is to present a characterization of a new silicon carbide (SiC) neutron detector fabricated at the Institute of Microelectronics of Barcelona (IMB-CNM-CSIC). The device is based on a 50μm thick p-n diode built in a 4H-SiC wafer. Performance studies were carried out under different neutron energy spectra, including thermal and quasi-monoenergetic fast neutrons at the CNA HiSPANoS facility. We implemented a method for the fabrication of enriched LiF conversion layers to use for the detection of thermal neutrons. The detector was proven to be capable of being used for thermal neutron detection with conversion layers of 10B and LiF. A detection efficiency of 6 ± 1% was achieved with a 25μm thick LiF conversion layer. It was also confirmed that the device can be employed for the detection of recoil nuclei and protons produced by fast neutrons. The spectra obtained experimentally were compared with PHITS simulations. This work represents the first step towards the design and fabrication of new SiC neutron detectors in the IMB-CNM-CSIC clean room with potential applications in various scientific and technological fields.
Ultra-Thin Plastic Scintillator-Based Proton Detector for Timing Applications
(Multidisciplinary Digital Publishing Institute (MDPI), 2025-02-06) Rodríguez Ramos, Mauricio; García López, Francisco Javier; Seimetz, Michael; Juan Morales, Jessica; Torres Muñoz, Carmen; Jiménez Ramos, María del Carmen; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Universidad de Sevilla. Departamento de Física Aplicada II; Junta de Andalucía; Generalitat Valenciana; Consejo Superior de Investigaciones Científicas (CSIC)
The development of advanced detection systems for charged particles in laser-based accelerators and the need for precise time of flight measurements have led to the creation of detectors using ultra-thin plastic scintillators, indicating their use as transmission detectors with low energy loss and minimal dispersion for protons around a few MeV. This study introduces a new detection system designed by the Institute for Instrumentation in Molecular Imaging for time of flight and timing applications at the National Accelerator Center in Seville. The system includes an ultra-thin EJ-214 plastic scintillator coupled with a photomultiplier tube and shielded by aluminized mylar sheets. The prototype installation as an external trigger system at the ion beam nuclear microprobe of the aforementioned facility, along with its temporal performance and ion transmission, was thoroughly characterized. Additionally, the scintillator thickness and uniformity were analyzed using Rutherford backscattering spectrometry. Results showed that the experimental thickness of the EJ-214 sheet differs by approximately 46% from the supplier specifications. The detector response to MeV protons demonstrates a strong dependence on the impact position but remains mostly linear with the applied working bias. Finally, single ion detection was successfully achieved, demonstrating the applicability of this new system as a diagnostic tool.
Experiments and Gyrokinetic Simulations of TCV Plasmas with Negative Triangularity in View of DTT Operations
(Institute of Physics Publishing, 2024) Balestri, A.; Mantica, P.; Mariani, A.; Bagnato, F.; Bolzonella, T.; Ball, J.; Coda, S.; Dunne, M.; Faitsch, M.; Innocente, P.; Viezzer, Eleonora; EUROfusion MST1 Team; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; EUROfusion Consortium
Negative triangularity (NT) scenarios in TCV have been compared to positive triangularity (PT) scenarios using the same plasma shapes foreseen for divertor tokamak test tokamak operations. The experiments provided a NT/PT L-mode pair and a PT H-mode with different heating mixes. Regardless of the heating mix, NT L-modes always reached higher values of plasma pressure with respect to PT L-modes with the same power and recovered the central pressure of PT H-mode scenarios heated with up to twice the injected power. The experimental analysis shows that this enhanced performance in NT is due to larger temperature and density gradients close to the edge ( ρ t o r = [ 0.8 − 1.0 ] ) and higher values of pressure at the separatrix. Local gyrokinetic simulations agree with the experimental results and are able to catch the effect of shaping alone. Integrated modeling performed with ASTRA-TGLF reproduces reasonably well the PT shot but is not able to fully capture the improvements in the NT shot.
8B Reaction Dynamics Researched at HIE-ISOLDE
(Editrice Compositori s.r.l., 2024) Spartà, R.; DiPietro, A.; Figuera, P.; Tengblad, O.; Moro Muñoz, Antonio Matías; Lei, J.; Martel, I.; Fernández García, Juan Pablo; Acosta, L.; Borge, M. J.G.; Onses, S. Viñal; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE). H2020
For the first time a measurement of 8B + 64Zn reaction has been performed at HIE-ISOLDE at CERN at energies around the Coulomb barrier, to understand how the debated halo structure of the light nucleus can affect reaction dynamics.
Conceptual Design of a Scintillator-Based Fast-Ion Loss Detector for the Wendelstein 7-X Stellarator
(IEEE, 2022) Van Vuuren, Anton Jansen; Lazerson, S. A.; Leviness, A.; García Muñoz, Manuel; Gates, D.; Galdón Quiroga, Joaquín; Hidalgo Salaverri, Javier; Rueda Rueda, José; García Domínguez, Javier; Ayllón Guerola, Juan Manuel; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Universidad de Sevilla. Departamento de Ingeniería Mecánica y de Fabricación; European Union (UE); Ministerio de Ciencia e Innovación (MICIN). España
A conceptual design of a scintillator-based fast-ion loss detector (FILD) has been developed for the Wendelstein 7-X stellarator (W7-X). Simulations using the Monte Carlo codes ASCOT5 and BEAMS3D have been performed to calculate the expected flux of neutral beam injection (NBI)-generated fast hydrogen ions onto the conceptual detector probe head. These fast-ion loss fluxes have been calculated for several magnetic field configurations as well as probe insertion positions. At the maximum insertion position, both co- and counter-going losses with high incident pitch angles are observed; however, at retracted positions, only co-going fast ions reach the probe head. The FILDSIM code has been used to optimize the geometry of the detector entrance and collimating elements to achieve a wide velocity space coverage as well as a high velocity–space resolution. A synthetic FILD signal is calculated for the expected loss distribution via forward modeling using the instrument response function. The synthetic signal is found to largely retain the velocity space features of the loss distribution.
Plutonium Signatures in a Dated Sediment Core as a Tool to Reveal Nuclear Sources in the Baltic Sea
(American Chemical Society, 2023) López Lora, Mercedes; Olszewski, G.; Chamizo, E.; Tornquist, P.; Pettersson, H.; Eriksson, Mats; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Swedish Radiation Safety Authority (SSM); Ministerio de Ciencia, Innovación y Universidades (MICINN). España
Plutonium distribution was studied in an undisturbed sediment core sampled from the Tvären bay in the vicinity of the Studsvik nuclear facility in Sweden. The complete analysis, including minor isotopes, of the Pu isotope composition (238Pu, 239Pu, 240Pu, 241Pu, 242Pu, and 244Pu) allowed us to establish the Pu origin in this area of the Baltic Sea and to reconstruct the Studsvik aquatic release history. The results show highly enriched 239Pu, probably originating from the Swedish nuclear program in the 1960s and 1970s and the handling of high burn-up nuclear fuel in the later years. In addition, the 244Pu/239Pu atomic ratio for the global fallout period between 1958 and 1965 is suggested to be (7.94 ± 0.31)·10-5. In the bottom layer of the sediment, dated 1953-1957, we detected a higher average 244Pu/239Pu ratio of (1.51 ± 0.11)·10-4, indicating the possible impact of the first US thermonuclear tests (1952-1958).
Isospin Dependence in Single-nucleon Removal Cross Sections Explained Through Valence-core Destruction Effects
(Elsevier, 2023) Gómez Ramos, Mario; Gómez Camacho, Joaquín José; Moro Muñoz, Antonio Matías; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Ciencia e Innovación (MICIN). España; Junta de Andalucía
The discrepancy between experimental data and theoretical calculations in one-nucleon removal reactions at intermediate energies (quantified by the so-called “quenching factors”) and its dependence on the isospin asymmetry of the nuclei has been an open problem in nuclear physics for the last fifteen years. In this work, we propose an explanation for this long-standing problem, which relies on the inclusion of the process of core destruction due to its interaction with the removed nucleon. To include this effect, we extend the commonly used eikonal formalism via an effective nucleon density, and apply it to a series of nucleon knockout reactions. The effect of core destruction is found to depend strongly on the binding energy of the removed nucleon, leading to a significant reduction of the cross section for deeply bound nucleons, which reduces the isospin dependence of the “quenching factors”, making them more consistent with the trends found in transfer and (p,pN) reactions.
Defect Engineering of Silicon with Ion Pulses from Laser Acceleration
(Springer Nature, 2023) Redjem, Walid; Amsellem, Ariel J.; Allen, Frances I.; Benndorf, Gabriele; Bin, Jianhui; Bulanov, Stepan; Esarey, Eric; Feldman, Leonard C.; Ferrer Fernández, Francisco Javier; García López, Francisco Javier; Schenkel, Thomas; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Office of Science. EE.UU.
Defect engineering is foundational to classical electronic device development and for emerging quantum devices. Here, we report on defect engineering of silicon with ion pulses from a laser accelerator in the laser intensity range of 1019 W cm−2 and ion flux levels of up to 1022 ions cm−2 s−1, about five orders of magnitude higher than conventional ion implanters. Low energy ions from plasma expansion of the laser-foil target are implanted near the surface and then diffuse into silicon samples locally pre-heated by high energy ions from the same laser-ion pulse. Silicon crystals exfoliate in the areas of highest energy deposition. Color centers, predominantly W and G-centers, form directly in response to ion pulses without a subsequent annealing step. We find that the linewidth of G-centers increases with high ion flux faster than the linewidth of W-centers, consistent with density functional theory calculations of their electronic structure. Intense ion pulses from a laser-accelerator drive materials far from equilibrium and enable direct local defect engineering and high flux doping of semiconductors.
Spectrometric Performance of SiC Radiation Detectors at High Temperature
(Elsevier, 2024) Jiménez Ramos, María del Carmen; García Osuna, Adrián; Rodríguez Ramos, Mauricio; Viezzer, Eleonora; Pellegrini, G.; Godignon, P.; Rafí, J. M.; Rius, G.; García López, Francisco Javier; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Universidad de Sevilla. Departamento de Física Aplicada II; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; Junta de Andalucía; Ministerio de Ciencia e Innovación (MICIN). España
In this work, we have investigated the performance of a 4H–SiC radiation sensor in the temperature range from 25 °C to 450 °C to explore its compatibility as detector of fast ion losses in plasma diagnostic of future nuclear fusion reactors. To simulate the escape of fusion-born alpha particles in D-T (deuterium-tritium) fusion plasmas, spectroscopic measurements were carried out in a vacuum chamber by irradiating the detector with a 3.5 MeV alpha beam from a Tandem accelerator. The detector was found to have an energy resolution ≤2% over the entire temperature range analyzed. Relevantly, the excellent spectrometric capabilities of the device have allowed us to calculate from experimental data, with unprecedented accuracy, the average energy required to create a single electron-hole pair in 4H–SiC as a function of temperature.
Description of continuum structures in a discrete basis: Three-body resonances and two-nucleon decays
(SciPost, 2020) Casal Berbel, Jesús; Rodríguez Gallardo, Manuela; Arias Carrasco, José Miguel; Gómez Camacho, Joaquín José; Fortunato, Lorenzo; Vitturi, Andrea; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Università degli Studi di Padova. Italia; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; European Union (UE). H2020
Weakly bound and unbound three-body nuclei are studied by using the pseudostate method within the hyperspherical formalism. After introducing the theoretical framework, the method is applied first to the 9Be nucleus, showing a good agreement with the available data for its low-lying dipole response. Then, recent results on the structure and decay of the two-neutron emitters 26O and 16Be are presented. In particular, the role of the n-n correlation in shaping their properties is discussed.
A rotary and reciprocating scintillator based fast-ion loss detector for the MAST-U tokamak
(American Institute of Physics, 2018) Rivero Rodríguez, Juan Francisco; García Muñoz, Manuel; Martin, R.; Galdón Quiroga, Joaquín; Ayllón Guerola, Juan Manuel; Akers, R. J.; García Vallejo, Daniel; González Martín, Javier; Rodríguez Ramos, Mauricio; Sanchis Sánchez, Lucía; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Commission (EC); Universidad de Sevilla
The design and unique feature of the first fast-ion loss detector (FILD) for the Mega Amp Spherical Tokamak - Upgrade (MAST-U) is presented here. The MAST-U FILD head is mounted on an axially and angularly actuated mechanism that makes it possible to independently adapt the orientation [0◦ , 90◦ ] and radial position [1.40 m, 1.60 m] of the FILD head, i.e., its collimator, thus maximizing the detector velocity-space coverage in a broad range of plasma scenarios with different q95. The 3D geometry of the detector has been optimized to detect fast-ion losses from the neutral beam injectors. Orbit simulations are used to calculate the strike map and predict the expected signals. The results show a velocity-space range of [4 cm, 13 cm] in gyroradius and [30◦ , 85◦ ] in pitch angle, covering the entire neutral beam ion energy range. The optical system will provide direct sight of the scintillator and simultaneous detection with two cameras, giving high spatial and temporal resolution. The MAST-U FILD will shed light on the dominant fast-ion transport mechanisms in one of the world’s two largest spherical tokamaks through absolute measurements of fast-ion losses.
Accelerator Mass Spectrometry (AMS) in Radioecology
(Elsevier, 2018) García León, Manuel; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Economía y Competitividad (MINECO). España
Accelerator Mass Spectrometry (AMS) provides with an excellent sensitivity for the determination of radionuclides in the environment. In fact, conventional radiometric techniques can hardly compete with AMS in the solution of many problems involving the measurement of very low levels of radioactivity in Nature. For that reason, during the last years AMS has become a powerful tool for Radioecology studies. In this paper a review is done on the evolution of AMS applications to the measurement of environmental radioactivity and, therefore, its contribution to the understanding of radionuclide behavior in Nature.For that, the advantages of using AMS to determine key nuclides as 129I, 14C, Pu-isotopes and others in different natural compartments will be discussed. The content of the paper is illustrated with the contributions to these studies of the Spanish National Center for Accelerators (CNA) AMS systems.
Implications of the Harmonization of [18F]FDG-PET/CT Imaging for Response Assessment of Treatment in Radiotherapy Planning
(MDPI, 2022) Jiménez Ortega, Elisa Eugenia; Agüera Rodríguez, Raquel; Ureba Sánchez, Ana María; Balcerzyk, Marcin; Wals Zurita, Amadeo; García Gómez, Francisco Javier; Leal Plaza, Antonio; Universidad de Sevilla. Departamento de Fisiología Médica y Biofísica; European Union (UE); Junta de Andalucía; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
The purpose of this work is to present useful recommendations for the use of [18F]FDG-PET/CT imaging in radiotherapy planning and monitoring under different versions of EARL accreditation for harmonization of PET devices. A proof-of-concept experiment designed on an anthropomorphic phantom was carried out to establish the most suitable interpolation methods of the PET images in the different steps of the planning procedure. Based on PET/CT images obtained by using these optimal interpolations for the old EARL accreditation (EARL1) and for the new one (EARL2), the treatment plannings of representative actual clinical cases were calculated, and the clinical implications of the resulting differences were analyzed. As expected, EARL2 provided smaller volumes with higher resolution than EARL1. The increase in the size of the reconstructed volumes with EARL1 accreditation caused high doses in the organs at risk and in the regions adjacent to the target volumes. EARL2 accreditation allowed an improvement in the accuracy of the PET imaging precision, allowing more personalized radiotherapy. This work provides recommendations for those centers that intend to benefit from the new accreditation, EARL2, and can help build confidence of those that must continue working under the EARL1 accreditation.

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