Artículos (Centro Nacional de Aceleradores)

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

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A view of the implanted SiC damage by Rutherford backscattering spectroscopy, spectroscopic ellipsometry, and transmission electron microscopy
(AIP Publishing, 2006) Battistig, G.; Khánh, N. Q.; Petrik, P.; Lohner, T.; Dobos, L.; Pécz, B.; García López, Francisco Javier; Morilla García, Yolanda; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
4H-SiC single crystalline substrates were implanted at room temperature with 150 keV Al+ ions using fluences of 4 1014, 1 1015, and 2 1015 cm−2 with current density of 2.5 A cm−2. The samples were subsequently annealed at 1100 °C in N2 for 1 h in order to analyze their structural recovery. The disorder induced in both sublattices by the Al+ ions was studied by backscattering spectrometry in channeling geometry with a 3.5 MeV He2+ beam. The results were compared with the optical properties of the samples measured by spectroscopic ellipsometry. In a previous work, we concluded that during the postimplantation annealing of a highly damaged SiC crystalline material the short distance order can be recovered, while the long distance disorder remains. We also presented the possibility to have grains of different polytypes oriented faraway from the original direction. Now, this alternative is confirmed by the cross-sectional transmission and high resolution electron microscopy studies, carried out to obtain information about the crystal structure.
Correlation between Mn oxidation state and magnetic behavior in Mn/ZnO multilayers prepared by sputtering
(AIP Publishing, 2007) Céspedes, E.; García López, Francisco Javier; García Hernández, M.; Andrés, A. de; Prieto, C.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
Compositional, microstructural, and magnetic characterization of ZnO 30 Å/Mn x n multilayers prepared by sputtering is presented to study the observed ferromagnetism in the Mn-ZnO system. The nominal Mn layer thickness, x, is varied from 3 to 60 Å, while the number of bilayers, n, is increased to maintain the total amount of Mn constant. Microstructure information was deduced from x-ray reflectivity, Mn oxidation state was determined by x-ray absorption spectroscopy, and magnetic properties were measured over a temperature range of 5–400 K. Magnetic behavior of these samples is found to be related to the Mn layer thickness x. Multilayers with x 30 Å exhibit ferromagnetism with a Curie temperature above 400 K, while mostly paramagnetic behavior is obtained for x15 Å. Magnetic behavior is discussed in terms of electronic and structural parameters of samples. Mn-ZnO interface effect is related to the ferromagnetic order of the samples, but it is not a sufficient condition. The essential role of the Mn oxidation state in the magnetic behavior of this system is pointed out. It is shown a correlation between the obtained ferromagnetism and a Mn oxidation state close to 2+.
Quantification of self-sputtering and implantation during pulsed laser deposition of gold
(AIP Publishing, 2008) Perea Folgueras, Ángel; Gonzalo, José; Budtz Jørgensen, C.; Epurescu, George; Siegel, Jan; Afonso Rodríguez, Carmen Nieves; García López, Francisco Javier; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
This work reports on the quantification of self-sputtering and implantation occurring during pulsed laser deposition of Au as a function of the laser fluence used to ablate the gold target. The experimental approach includes, on one hand, in situ electrical Langmuir and optical two-dimensional imaging probes for determining, respectively, ion and excited neutral kinetic energy distributions. On the other hand, it includes determination of the density of i ions reaching a substrate, and ii gold atoms deposited on a substrate as well as of a proportion of atoms that are self-sputtered. The experimental results supported by numerical analysis show that self-sputtering and implantation are both dominated by ions having kinetic energies 200 eV. They are a fraction 0.60–0.75 of the species arriving to the substrate for ablation laser fluences 2.7– 9.0 J cm−2. Self-sputtering yields in the range 0.60–0.86 are determined for the same fluence range.
Induced ferromagnetism in Mn3N2 phase embedded in Mn/Si3N4 multilayers
(AIP Publishing, 2009) Céspedes, E.; Román, E.; Huttel, Yves; Chaboy Nalda, Jesús; García López, Francisco Javier; Andrés, A. de; Prieto, C.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
Room temperature ferromagnetism has been obtained for different sets of Mn/Si3N4 multilayers prepared by sputtering. In order to find the most suitable conditions to stabilize the ferromagnetic ordering in this system, the evolution of the magnetic properties has been studied for films in which the Si3N4 layer thickness was maintained constant while that of the Mn layer was varied, Mn tm/Si3N4 3.4 nm n, and conversely, in Mn 0.7 nm/Si3N4 tsn 43 samples, in which the Mn layer thickness was kept constant while varying the Si3N4 layer thickness. Structural, compositional, electronic and magnetic characterizations have been performed by means of x-ray reflectometry, Rutherford backscattering spectrometry, x-ray photoemission spectroscopy, x-ray absorption, and superconducting quantum interference device for further knowledge of the magnetic-structural relationship in this system. Our results show that the peculiar magnetic behavior of these films is mainly related to the stabilization of a slightly distorted Mn3N2 phase that is induced by the Si3N4 at the interfaces. For samples with larger Mn layer thickness, metallic Mn and Mn3N2 phases coexist, which leads to a reduction of the total magnetization per Mn atom due to the presence of metallic Mn. For small Mn layer thickness tm 0.86 nm, where noncontinuous Mn3N2 layers are formed, the magnetization decreases noticeably due to the superparamagnetic size limit. It has been found that the best conditions for the stabilization of the ferromagnetism in this system occur when both, the manganese-rich and the silicon nitride layers, are continuous and with similar thickness, close to 3.5 nm.
Development of Slowed Down Beams at the Fragment Separator for FAIR
(Jagiellonian University, 2011) Naqvi, F.; Boutachkov, P.; Górska, M.; Gerl, J.; Farinon, F.; Gregor, E.T.; González Álvarez, Marcos Aurelio; Wollersheim, H.J.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
The feasibility studies of the slowed down beam setup involving deceleration of a 64Ni beam at 250 MeV/u to 13 MeV/u in a thick Al degrader was performed at the FRagment Separator (FRS) at GSI. The experimentally measured energy spread and the nuclear reaction yields in the degrader are in good agreement with simulations.
Determination of 25 trace element concentrations in biological reference materials by ICP-MS following different microwave-assisted acid digestion methods based on scaling masses of digested samples
(2013) Abril Hernández, José María; Enamorado Báez, Santiago Miguel; Gómez Guzmán, José Manuel
Matrix metalloproteinase 9 (MMP-9) is indispensable for long term potentiation in the central and basal but not in the lateral nucleus of the amygdala
(Frontiers Media, 2015) Balcerzyk, Marcin; Gorkiewicz, Tomasz; Kaczmarek, Leszek; Knapska, Ewelina; National Science Center. Poland
It has been shown that matrix metalloproteinase 9 (MMP-9) is required for synaptic plasticity, learning and memory. In particular, MMP-9 involvement in long-term potentiation (LTP, the model of synaptic plasticity) in the hippocampus and prefrontal cortex has previously been demonstrated. Recent data suggest the role of MMP-9 in amygdala-dependent learning and memory. Nothing is known, however, about its physiological correlates in the specific pathways in the amygdala. In the present study we show that LTP in the basal and central but not lateral amygdala (LA) is affected by MMP-9 knock-out. The MMP-9 dependency of LTP was confirmed in brain slices treated with a specific MMP-9 inhibitor. The results suggest that MMP-9 plays different roles in synaptic plasticity in different nuclei of the amygdala.
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.
On the Entropy of Oscillator-Based True Random Number Generators under Ionizing Radiation
(MDPI, 2018) Martin, Honorio; Martin-Holgado, Pedro; Peris-Lopez, Pedro; Morilla García, Yolanda; Entrena, Luis; Universidad de Sevilla-CSIC. Centro Nacional de Aceleradores
The effects of ionizing radiation on field-programmable gate arrays (FPGAs) have been investigated in depth during the last decades. The impact of these effects is typically evaluated on implementations which have a deterministic behavior. In this article, two well-known true-random number generators (TRNGs) based on sampling jittery signals have been exposed to a Co-60 radiation source as in the standard tests for space conditions. The effects of the accumulated dose on these TRNGs, an in particular, its repercussion over their randomness quality (e.g., entropy or linear complexity), have been evaluated by using two National Institute of Standards and Technology (NIST) statistical test suites. The obtained results clearly show how the degradation of the statistical properties of these TRNGs increases with the accumulated dose. It is also notable that the deterioration of the TRNG (non-deterministic component) appears before that the degradation of the deterministic elements in the FPGA, which compromises the integrated circuit lifetime.
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.
Total Ionizing Dose Effects on a Delay-Based Physical Unclonable Function Implemented in FPGAs
(MDPI, 2018) Martín, Honorio; Martín Holgado, Pedro; Morilla García, Yolanda; Entrena, Luis; San Millán, Enrique; Ministerio de Economía y Competitividad (MINECO). España
Physical Unclonable Functions (PUFs) are hardware security primitives that are increasingly being used for authentication and key generation in ICs and FPGAs. For space systems, they are a promising approach to meet the needs for secure communications at low cost. To this purpose, it is essential to determine if they are reliable in the space radiation environment. In this work we evaluate the Total Ionizing Dose effects on a delay-based PUF implemented in SRAM-FPGA, namely a Ring Oscillator PUF. Several major quality metrics have been used to analyze the evolution of the PUF response with the total ionizing dose. Experimental results demonstrate that total ionizing dose has a perceptible effect on the quality of the PUF response, but it could still be used for space applications by making some appropriate corrections.
A Compact Model to Evaluate the Effects of High Level C++ Code Hardening in Radiation Environments
(MDPI, 2019) Reyneri, Leonardo Maria; Serrano Cases, Alejandro; Morilla García, Yolanda; Cuenca Asensi, Sergio; Martínez Álvarez, Antonio; Universidad de Sevilla. Centro Nacional de Aceleradores
A high-level C++ hardening library is designed for the protection of critical software against the harmful effects of radiation environments that can damage systems. A mathematical and empirical model to predict system behavior in the presence of radiation induced faults is also presented. This model generates a quick evaluation and adjustment of several reliability vs. performance trade-offs, to optimize radiation hardening based on the proposed C++ hardening library. Several simulations and irradiation campaigns with protons and neutrons are used to build the model and to tune it. Finally, the effects of our hardening approach are compared with other hardened and non-hardened approaches.
Impact of Gamma Radiation on Dynamic RDSON Characteristics in AlGaN/GaN Power HEMTs
(MDPI, 2019) Martínez, Pedro J.; Maset, Enrique; Martín Holgado, Pedro; Morilla García, Yolanda; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear
GaN high-electron-mobility transistors (HEMTs) are promising next-generation devices in the power electronics field which can coexist with silicon semiconductors, mainly in some radiation-intensive environments, such as power space converters, where high frequencies and voltages are also needed. Its wide band gap (WBG), large breakdown electric field, and thermal stability improve actual silicon performances. However, at the moment, GaN HEMT technology suffers from some reliability issues, one of the more relevant of which is the dynamic on-state resistance (RON_dyn) regarding power switching converter applications. In this study, we focused on the drain-to-source on-resistance (RDSON) characteristics under 60Co gamma radiation of two different commercial power GaN HEMT structures. Different bias conditions were applied to both structures during irradiation and some static measurements, such as threshold voltage and leakage currents, were performed. Additionally, dynamic resistance was measured to obtain practical information about device trapping under radiation during switching mode, and how trapping in the device is affected by gamma radiation. The experimental results showed a high dependence on the HEMT structure and the bias condition applied during irradiation. Specifically, a free current collapse structure showed great stability until 3.7 Mrad(Si), unlike the other structure tested, which showed high degradation of the parameters measured. The changes were demonstrated to be due to trapping effects generated or enhanced by gamma radiation. These new results obtained about RON_dyn will help elucidate trap behaviors in switching transistors.
Natural radionuclides (NORM) in a Moroccan river affected by former conventional metal mining activities
(Elsevier, 2019) Manjón Collado, Guillermo; Mantero Cabrera, Juan; Vioque Romero, Ignacio; Díaz Francés, Inmaculada; Galván Moreno, José Antonio; Chakiri, Said; Choukri, Abdelmajid; García-Tenorio García-Balmaseda, Rafael; Universidad de Sevilla. Departamento de Física Aplicada II; Centro Nacional de Aceleradores
The main aim of this work was to determine the levels of multiple natural radionuclides in an aquatic system (Moulouya river, Morocco) impacted by multiple abandoned Zinc and Lead mines. 238U, 234U, 232Th, 230Th and 210Po were determined by alpha-particlespectrometry in water and sediment samples collected along the river and in samples from three pit lakes of abandoned mines, located in the Upper Moulouya catchment area. The results enabled the analysis of the different levels of impact of former mining activities, depending on the natural radionuclides. While the activity concentrationof U-isotopes in Moulouya river water was slightly elevated in the vicinity of abandoned mine wastes, other natural radionuclides (Th-isotopes and 210Po) levels were typical of a natural environment. This fact is clearly reflected in the magnitude and range observed in the distribution coefficients for the different radionuclides analyzed.
Human oocytes and zygotes are ready for ultra-fast vitrification after 2 minutes of exposure to standard CPA solutions
(Nature Research, 2019) Gallardo Molina, Miguel; Sáenz Cuesta, Jaime Luis; Risco, Ramón; Universidad de Sevilla. Departamento de Física Aplicada III
Vitrification of human oocytes and embryos in different stages of development is a key element of daily clinical practice of in vitro fertilization treatments. Despite the cooling and warming of the cells is ultra-fast, the procedure as a whole is time consuming. Most of the duration is employed in a long (8–15 minutes), gradual or direct exposure to a non-vitrifying cryoprotectant solution, which is followed by a short exposure to a more concentrated vitrifying solution. A reduction in the duration of the protocols is desirable to improve the workflow in the IVF setting and reduce the time of exposure to suboptimal temperature and osmolarity, as well as potentially toxic cryoprotectants. In this work it is shown that this reduction is feasible. In silico (MatLab program using two-parameter permeability model) and in vitro observations of the oocytes’ osmotic behaviour indicate that the dehydration upon exposure to standard cryoprotectant solutions occurs very fast: the point of minimum volume of the shrink-swell curve is reached within 60 seconds. At that point, intracellular water ejection is complete, which coupled with the permeation of low molecular weight cryoprotectants results in similar intracellular and extracellular solute concentrations. This shows that prolonging the exposure to the cryoprotectant solutions does not improve the cytosolic glass forming tendency and could be avoided. To test this finding, human oocytes and zygotes that were donated for research were subjected to a shortened, dehydration-based protocol, consisting of two consecutive exposures of one-minute to two standard cryoprotectant solutions, containing ethylene glycol, dimethyl sulfoxide and sucrose. At the end of this two-minute dehydration protocol, the critical intracellular solute concentration necessary for successful vitrification was attained, confirmed by the post-warming survival and ability to resume cytokinesis of the cells. Further studies of the developmental competency of oocytes and embryos would be necessary to determine the suitability of this specific dehydration protocol for clinical practice, but based on our results, short times of exposure to increasingly hypertonic solutions could be a more time-efficient strategy to prepare human oocytes and embryos for vitrification.
Accurate,robust and harmonized implementation of morpho-functional imaging in treatment planning for personalized radiotherapy
(Public Library of Science, 2019-01-09) Jiménez Ortega, Elisa Eugenia; Ureba Sánchez, Ana María; Baeza, José Antonio; Pereira Barbeiro, Ana Rita; Balcerzyk, Marcin; Parrado-Gallego, Ángel; Wals-Zurita, Amadeo; García-Gómez, Francisco Javier; Leal Plaza, Antonio; Universidad de Sevilla. Departamento de Fisiología Médica y Biofísica; Junta de Andalucía; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)
In this work we present a methodology able to use harmonized PET/CT imaging in dose painting by number (DPBN) approach by means of a robust and accurate treatment planning system. Image processing and treatment planning were performed by using a Matlab-based platform, called CARMEN, in which a full Monte Carlo simulation is included. Linear programming formulation was developed for a voxel-by-voxel robust optimization and a specific direct aperture optimization was designed for an efficient adaptive radiotherapy implementation. DPBN approach with our methodology was tested to reduce the uncertainties associated with both, the absolute value and the relative value of the information in the functional image. For the same H&N case, a single robust treatment was planned for dose prescription maps corresponding to standardized uptake value distributions from two different image reconstruction protocols: One to fulfill EARL accreditation for harmonization of [18F]FDG PET/CT image, and the other one to use the highest available spatial resolution. Also, a robust treatment was planned to fulfill dose prescription maps corresponding to both approaches, the dose painting by contour based on volumes and our voxel-by-voxel DPBN. Adaptive planning was also carried out to check the suitability of our proposal. Different plans showed robustness to cover a range of scenarios for implementation of harmonizing strategies by using the highest available resolution. Also, robustness associated to discretization level of dose prescription according to the use of contours or numbers was achieved. All plans showed excellent quality index histogram and quality factors below 2%. Efficient solution for adaptive radiotherapy based directly on changes in functional image was obtained. We proved that by using voxel-by-voxel DPBN approach it is possible to overcome typical drawbacks linked to PET/CT images, providing to the clinical specialist confidence enough for routinely implementation of functional imaging for personalized radiotherapy.
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.
Determining B(E1) distributions of weakly bound nuclei from breakup cross sections using Continuum Discretized Coupled Channels calculations. Application to 11Be
(Elsevier, 2020) Moro Muñoz, Antonio Matías; Lay Valera, José Antonio; Gómez Camacho, Joaquín José; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Ministerio de Ciencia, Innovación y Universidades (MICINN). España; European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER); European Union (UE); Ministerio de Ciencia, Innovación y Universidades de España y fondos FEDER FIS2017-88410-P y RTI2018-098117-B-C21; Programa de investigación e innovación Horizonte 2020 de la Unión Europea Subvención No. 654002.
A novel method to extract the B(E1) strength of a weakly bound nucleus from experimental Coulomb dissociation data is proposed. The method makes use of continuum discretized coupled channels (CDCC) calculations, in which both nuclear and Coulomb forces are taken into account to all orders. This is a crucial advantage with respect to the standard procedure based on the Equivalent Photon Method (EPM) which does not properly take into account nuclear distortion, higher order coupling effects, or Coulomb- nuclear interference terms. The systematic and statistical uncertainties of this procedure are evaluated. The procedure is applied to the 11Be nucleus using two sets of available experimental data at different energies, for which seemingly incompatible B(E1) have been reported using the EPM. We show that the present procedure gives consistent B(E1) strengths, thus solving the aforementioned long-standing discrepancy between the two measurements.
Destruction of the cosmic γ-ray emitter 26 Al in massive stars: Study of the key 26 Al ( n , p ) reaction
(American Physical Society, 2021) Lederer Woods, Claudia; Woods, P. J.; Davinson, T.; Kahl, D.; Lonsdale, S. J.; Aberle, O.; Chiaveri, Enrico; Cortés Giraldo, Miguel Antonio; Ferrer Fernández, Francisco Javier; Guerrero Sánchez, Carlos; Lerendegui Marco, Jorge; Quesada Molina, José Manuel; Sabaté Gilarte, Marta; Žugec, P.; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; Austrian Science Fund (FWF). Austria; Consejo de Instalaciones Científicas y Tecnológicas (STFC). Reino Unido; Consejo Europeo de Investigación. Unión Europea
The 26 Al (n ,p) 26 Mg reaction is the key reaction impacting on the abundances of the cosmic y-ray emitter 26 Al produced in massive stars and impacts on the potential pollution of the early solar system with 26 Al by asymptotic giant branch stars. We performed a measurement of the 26 Al ( n , p ) 26 Mg cross section at the high-flux beam line EAR-2 at the n_TOF facility (CERN). We report resonance strengths for eleven resonances, nine being measured for the first time, while there is only one previous measurement for the other two. Our resonance strengths are significantly lower than the only previous values available. Our cross-section data range to 150 keV neutron energy, which is sufficient for a reliable determination of astrophysical reactivities up to 0.5 GK stellar temperature.
Probing proton halo effects in the 8B+64Zn collision around the Coulomb barrier
(Elsevier, 2021) Spartà, Roberta; Di Pietro, Alessia; Figuera, Pierpaolo; Tengblad, Olof; Moro Muñoz, Antonio Matías; Martel Bravo, Ismael; Fernández García, Juan Pablo; Viñals, Silvia; Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear; European Union (UE); Istituto Nazionale di Fisica Nucleare (INFN) Italia; Science and Technology Facilities Council (STFC) Reino Unido
Proton halo effects in the 8B+64Zn reaction at an energy around 1.5 times the Coulomb barrier have been studied at HIE-ISOLDE CERN using, for the first time, the only existing postaccelerated 8B beam. This, together with the use of a high granularity and large solid angle detection system, allowed for a careful mapping of the elastic angular distribution, especially in the Coulomb-nuclear interference region. Contrary to what is observed for the one-neutron halo nucleus 11Be on the same target in a similar energy range, the analysis of the elastic scattering angular distribution shows only a modest suppression of the Coulomb-nuclear interference peak, with no remarkable enhancement of the total reaction cross-section. Inclusive angular and energy distributions of 7Be produced in direct reaction processes have also been measured. The comparison of these data with the results of theoretical calculations for the elastic and non-elastic breakup contributions indicate that both processes are important. Overall, the experimental data suggest a 8B collision dynamics at the barrier very different from the one of neutron halo nuclei, showing only modest effects of coupling to continuum. This behaviour can be interpreted as due to the presence of the additional Coulomb interactions halo-core and halo-target together with the presence of the centrifugal barrier felt by the valence proton of 8B.

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