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The present paper is focused on our recent efforts to study the production and identification of neutron-rich medium-mass rare isotopes from peripheral reactions at beam energies around and below the Fermi energy. We obtained high-quality experimental data from a recent experiment with the MAGNEX spectrometer at the INFN-LNS in Catania, Italy. The main aim of this experiment was to check the feasibility of ejectile identification in this energy regime with the use of a large acceptance magnetic spectrometer. Our developed technique for particle identification depends mainly on a reconstruction of both the atomic number Z and the ionic charge q of the ions, followed by the identification of the mass. Our method was successfully applied to identify neutron-rich ejectiles from multinucleon transfer from the reaction of 70Zn (15 MeV/nucleon) + 64Ni. Preliminary results indicate that the extracted experimental distributions, along with comparisons with the theoretical models could help us to shed light to the complex reaction mechanism of multinucleon transfer in this energy regime.

We will present a recent experiment for elastic scattering of 7Be+natZr at five sub – and near- barrier energies, namely at 21.5, 22.5, 24, 27 and 28 MeV, for determining the optical potential. The experiment was performed at the TriSol radioactive beam facility of Notre Dame University, simultaneously with elastic scattering and breakup measurements of 8B+90Zr , the last performed at 28MeV. This optical potential will be used as one of the coupling potentials in our CDCC calculations for 8B. Further more we will look for the energy dependence of the potential and its resemblance to either the one exhibited by 7Li or the one by 6Li, extracting useful conclusions about their structure. Preliminary data are presented and discussed.

The present work is focused on our efforts to produce and identify neutron-richrare isotopes from peripheral reactions below the Fermi energy. High-quality experimental data were obtained from a recent experiment with the MAGNEX spectrometer at INFN-LNS in Catania, Italy. The main goal of this effort is to describe the adopted identification techniques used to analyze the data from the reaction 70 Zn (15 MeV/nucleon) + 64 Ni. The particle identification procedure is based on a novel approach that involves the reconstruction of both the atomic number Z and the ionic charge q of the ions, followed by the identification of themass. Our method was successfully applied to identify neutron-rich ejectiles from multinucleon transfer in the above reaction 70 Zn + 64 Ni at 15 MeV/nucleon. The analysis of the data is ongoing. We expect to obtain the angular and momentum distributions of the fragments, along with their production cross sections. These data, along with comparisons with theoretical models are expected to contribute to a better understanding of the complex reaction mechanisms of multinucleon transfer that dominate this energy regime.

The aim of the NUMEN project is to access the Nuclear Matrix Elements (NME), involved in the half life of the neutrinoless double beta decay (0νββ), by measuring the cross sections of Heavy Ions (HI) induced Double Charge Exchange (DCE) reactions with high accuracy. First evidence of the possibility to get quantitative information about NME from experiments is shown in the reaction 40Ca(18O,18Ne)40Ar at 270 MeV, performed with MAGNEX spectrometer using Superconducting Cyclotron (CS) beams at INFN - Laboratory Nazionali del Sud (LNS) in Catania. Preliminary tests on 116Sn and 116Cd target are already performed. High beam intensity is the new frontiers for these studies.

We acknowledge support from CICYT via contract FPA2009-07387, FPA2009-08848, FPA2010-22131-C02-01 and FPA2009- 07653. One of us (M.C.) acknowledges the support of the CSIC-Costa Rica fellowship program.

The rate of increase and decay of radio contamination secreted in sheep's milk, resulting from a constant level of radiocesium in the animals' diet, was investigated. Ten lactating ewes were used in the experiment. For a period of 12 d the animals fed on contaminated grass, resulting in a daily radiocesium intake of 832 Bq per animal. They were subsequently returned to a contamination-free diet and were monitored for another 9 d. Throughout the period of the experiment, 134Cs and 137Cs concentrations in the animals' milk were measured daily with an 18% efficiency, high-resolution Ge detector. The data were in satisfactory agreement with the predictions of a simple two-compartment theory. The transfer coefficient, describing the steady-state equilibrium in this model, was measured as fm = 0.058 +/- 0.007 dL-1. Health Phys

Health Phys

One hundred-two samples of colostral milk, collected during spring of 1987, approximately one year after the reactor accident at Chernobyl, were measured for radiocesium contamination. The data showed a normal-type distribution with a mean contamination concentration of 16.4 Bq L-1. A weak correlation of the data to the mothers' diet was established by taking into account four of the main staples in the area. The corresponding transfer coefficient was deduced with a value of fm = 0.06 +/- 0.03 d L-1. The resultant effective dose received by breast-feeding infants was estimated, on the average, as 0.012 mrem d-1. Health Phys