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El pdf del artículo es la versión pre-print: arXiv:1004.1911v1 ; We present an optical model (OM) analysis of the elastic scattering data of the reactions 6He+27Al and 6He+208Pb at incident energies around the Coulomb barrier. The bare part of the optical potential is constructed microscopically by means of a double folding procedure, using the São Paulo prescription without any renormalization. This bare interaction is supplemented with a Coulomb dipole polarization (CDP) potential, which takes into account the effect of the dipole Coulomb interaction. For this CDP potential, we use an analytical formula derived from the semiclassical theory of Coulomb excitation. The rest of the optical potential is parametrized in terms of Woods-Saxon shapes. In the 6He+208Pb case, the analysis confirms the presence of long range components, in agreement with previous works. Four-body Continuum-Discretized Coupled-Channels calculations have been performed in order to better understand the features of the optical potentials found in the OM analysis. This study searches to elucidate some aspects of the optical potential of weakly bound systems, such as the dispersion relation and the long range (attractive and absorptive) mechanisms. © 2010 Elsevier B.V. ; This work has been supported by the Spanish Ministerio de Ciencia e Innovación under project FPA2006-13807-C02-01, the local government of Junta de Andalucía under the excellence project P07-FQM-02894 and the Spanish Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042). ; Peer Reviewed

El pdf del artículo es la versión pre-print: arXiv:1006.1787v3 ; The elastic and α-production channels for the 6He+208Pb reaction are investigated at energies around the Coulomb barrier (Elab=14, 16, 18, 22, and 27 MeV). The effect of the two-neutron transfer channels on the elastic scattering has been studied within the Coupled-Reaction-Channels (CRC) method. We find that the explicit inclusion of these channels allows a simultaneous description of the elastic data and the inclusive α cross sections at backward angles. Three-body Continuum-Discretized Coupled-Channels (CDCC) calculations are found to reproduce the elastic data, but not the transfer/breakup data. The trivial local polarization potential (TLP) derived from the CRC and CDCC calculations are found to explain the features found in previous phenomenological optical model calculations for this system. © 2010 Elsevier B.V. ; This work has been supported by the Spanish Ministerio de Ciencia e Innovación under projects FPA2009-08848, FPA2009-07653, by the local government of Junta de Andalucía under project P07-FQM-02894 and the Spanish Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042). ; Peer Reviewed

We report on systematical optical model (OM) and continuum discretized coupled channel (CDCC) calculations applied to describe the elastic scattering angular distributions of exotic and stable nuclei projectiles on heavy targets. Our optical potential (OP) is composed of the nuclear microscopic double folding São Paulo potential (SPP), derived from the nonlocal nature of the interaction, and the Coulomb dipole polarization (CDP) potential, derived from the semiclassical theory of Coulomb excitation. The OP is compared to the trivial equivalent local potential (TELP), extracted from CDCC calculations. The OM and CDCC predictions corroborate each other and account for important differences in the nuclei reaction mechanisms, which are directly related to their structural properties. Thus, OM and CDCC establish a common basis for analyzing or even predicting exotic and stable nuclei reactions. ; This work was supported by the Ministry of Science, Innovation and Universities of Spain, through the project PGC2018-096994-B-C21. This work was also partially supported by the Spanish Ministry of Economy and Competitiveness, the European Regional Development Fund (FEDER), under Project No. FIS2017-88410-P and by the European Union's Horizon 2020 research and innovation program, under Grant Agreement No. 654002. J.C. acknowledges support by SID funds 2019 (Investimento Strategico di Dipartimento, Universittí degli Studi di Padova, Italy) under Project No. CASA_SID19_01.

New experimental results for the elastic scattering of 6 He on 64Zn at incident energies of 15.0 and 18.0 MeV and 4 He at 17.5 MeV along with results already published at 10.0 and 13.6 MeV, are presented. Elastic and α experimental cross sections are compared with coupled-reaction-channel, continuum-discretized coupledchannel, and DWBA inclusive-breakup models. The large yield of α particles observed at all measured energies can be explained by considering a nonelastic breakup mechanism. ; This work was partially supported by the Spanish Ministerio de Economía y Competitividad and FEDER funds (Projects No. FIS2014-53448-C2-1-P, No. FIS2017-88410-P, and No. FPA2016-77689-C2-1-R) and by the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 654002. ; Peer reviewed

Presented at the XXXIII Mazurian Lakes Conference on Physics, Piaski, Poland, September 1–7, 2013.-- et al. ; New data for the reaction 11Be on 197Au at E lab = 31:9 MeV are presented. The angular distributions of the inelastically scattered 11Be and the 10Be fragments coming from the 11Be dissociation have been extracted and compared with semiclassical and coupled-channels calculations in an angular range θlab = 13deg;-46deg; for the detected Be fragment. ; This work was supported by the Spanish Government under the projects FPA2009-07387, FPA2009-07653, FPA2009-08848, FPA2012-32443 and Consolider CPAN CSD2007-00042; the Helmholtz Association (HGT) through the Nuclear Astrophysics Virtual Institute (VH-VI-417); ATI Sistemas; a Natural Sciences and Engineering Research Council of Canada grant. TRIUMF receives federal funding via a contribution agreement through the National Research Council of Canada. ; Peer Reviewed