D. Escrig

α-particle production in the scattering of 6He by 208Pb at energies around the Coulomb barrier

New experimental data from the scattering of 6He + 208Pb at energies around and below the Coulomb barrier are presented. The yield of breakup products coming from projectile fragmentation is dominated by a strong group of α particles. The energy and angular distribution of this group have been analyzed and compared with theoretical calculations. This analysis indicates that the α particles emitted at backward angles in this reaction are mainly due to two-neutron transfer to weakly bound states of the final nucleus.

Near‐barrier scattering of 6He and 11Be

Experiments on halo nuclei at energies around the Coulomb barrier can provide good quality data on elastic, inelastic, breakup and nucleon transfer reactions. This information turns out to be very important to understand the structure and dynamics of these exotic nuclei. In this work we present relevant results obtained from recent scattering experiments of 11Be and 6He on heavy targets at energies around the Coulomb barrier. Our data exhibit strong absorption effects in the elastic channel. The role played by transfer and breakup channels, and the coupling to the continuum, are studied using CDCC and DWBA calculations.

Scattering of (6)He at energies around the Coulomb barrier

We have measured elastic cross sections of the scattering of 6 He at E Lab = 14, 16, 17,18 and 22 MeV on 208 Pb in the angular ranges of 20°-64° and 135°-170°. A significant amount of 4 He events is found at energies well below the Coulomb barrier, that becomes dominant above it. Optical model calculations have been performed including a dynamic polarization potential. Very large imaginary diffuseness parameter is needed in order to describe the experimental distributions.

Study Of The Scattering Of Halo Nuclei Around The Coulomb Barrier

During the past ten years the present collaboration has carried out several experiments related with the study of radioactive nuclei. One of the topics in which we have centered our research, is the scattering of halo nuclei at energies around the Coulomb barrier. As part of this study, we present in this work a review of the results obtained from the scattering of 6He, 11Be and 11Li. The presence of a “halo” in these exotic nuclei is found to have a striking effect on the dynamics of these reactions, making their study an interesting experimental problem and a challenge for existing reaction theories.

Understanding 6He induced reactions at energies around the Coulomb barrier

Recent developments aimed to understand the observed features arising in the scattering of the Borromean nucleus 6He on heavy targets are discussed and compared with recent data for 6He+208Pb measured at the RIB facility at Louvain‐la‐Neuve at energies around the Coulomb barrier. The analysis of the elastic scattering data in terms of the optical model, reveals the presence of a long range absorption mechanism, that manifests in the form of a large value of the imaginary diffuseness parameter. The elastic data have been also compared with three—body CDCC calculations, based on a di‐neutron model of 6He, and four—body CDCC calculations, based on a more realistic three‐body model of this nucleus. Finally, the angular and energy distribution of α particles emitted at backward angles are discussed and compared with different theoretical approaches. We find that these α particles are produced mainly by a two‐neutron transfer mechanism to very excited states in the residual nucleus.

Scattering of 6He at energies around the Coulomb barrier

We have measured elastic cross sections of the scattering of 6 He at E Lab = 14, 16, 17,18 and 22 MeV on 208 Pb in the angular ranges of 20°-64° and 135°-170°. A significant amount of 4 He events is found at energies well below the Coulomb barrier, that becomes dominant above it. Optical model calculations have been performed including a dynamic polarization potential. Very large imaginary diffuseness parameter is needed in order to describe the experimental distributions.

IOPscience - Scattering of 6He at energies around the Coulomb barrier

We have measured elastic cross sections of the scattering of 6 He at E Lab = 14, 16, 17,18 and 22 MeV on 208 Pb in the angular ranges of 20°-64° and 135°-170°. A significant amount of 4 He events is found at energies well below the Coulomb barrier, that becomes dominant above it. Optical model calculations have been performed including a dynamic polarization potential. Very large imaginary diffuseness parameter is needed in order to describe the experimental distributions.

Scattering of6He at energies around the Coulomb barrier

We have measured elastic cross sections of the scattering of 6 He at E Lab = 14, 16, 17,18 and 22 MeV on 208 Pb in the angular ranges of 20°-64° and 135°-170°. A significant amount of 4 He events is found at energies well below the Coulomb barrier, that becomes dominant above it. Optical model calculations have been performed including a dynamic polarization potential. Very large imaginary diffuseness parameter is needed in order to describe the experimental distributions.

Rotational bands in neutron-rich 160-162Ho

We have studied the high spin states in 160–162Ho in order to investigate the properties of the rotational bands and their dependence on the single particle orbits involved. The reaction 158,160Gd(7Li,xn) at 56 MeV were used to produce the Ho isotopes of interest. In all three Ho isotopes the known rotational bands have been significantly extended. New band‐crossings have been observed for the first time in this work.

Beta decay of 76Sr using the Total Absorption Spectrometer “Lucrecia” at ISOLDE‐CERN

A new Total Absorption Spectrometer (TAS) called “Lucrecia” has been installed at ISOLDE (CERN) to investigate the β‐decay of some nuclei with A≈70–80 in the vicinity of the N=Z line. In this work we report on the decay of the N=Z nucleus 76Sr, measured with a TAS for the first time. The Gamow‐Teller strength distribution B(GT) for this decay is presented and compared with theoretical calculations.