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[en] Total reaction cross-sections of neutron rich nuclei from C to Mg in a thick Si-target have been measured using the detection of the associated γ-rays in a 4Π-geometry. This cross-section strongly increases with neutron excess, indicating an increase of as much as 15% of the reduced strong absorption radius with respect to stable nuclei
[en] Full text: Exotic nuclei beyond the 132Sn double-shell closure are influenced by both the Sn superfluidity and the evolving collectivity only few nucleons away. Toward even more neutron-rich nuclei, especially at intermediate mass number, interplay between single-particle and collective particle-hole excitations compete. In some cases with the extreme addition of neutrons also other effects as the formation of neutron skin , stabilization as sub-shell gaps , and/or orbital crossings  may be expected. The knowledge of nuclear ingredients is especially interesting beyond 132Sn and little is known on how the excitations modes develop with the addition of both protons and neutrons [4-7] and for example systematic prompt and decay lifetime studies can be a very sensitive probe. Recently, we have approached this region of nuclei in several measurements following fission as 238U on 9Be target, within the EURICA project [8-9], n-induced fission on 235U/241Pu targets using prompt-decay spectroscopy within the EXILL/FATIMA campaigns [10-11], as well as in decay spectroscopy at LOHENGRIN. Examples from these studies on several nuclei in the region will be presented together with the possible interpretation of the new data.
[en] We discuss the usefulness of the double charge-exchange reactions (DCX) for the production of the neutron-rich Λ-hypernuclei. We believe the (π-, K+) reaction is one of the most promising DCX reactions, and propose to produce the neutron-rich Λ-hypernuclei, Λ6H and Λ9He, at the J-PARC 50 GeV PS by the reaction (J-PARC E10 experiment). The design of the experiment is presented. (author)
[en] Transfer reactions have been used for many years to understand the shell structure of nuclei. Recent studies with rare-isotope beams extend this work and make it possible to probe the evolution of shell structure far beyond the valley of stability, requiring measurements in inverse kinematics. We present a novel technical approach to measurements in inverse kinematics, and apply this method to different transfer reactions, each of which probes different properties of light, neutron-rich nuclei
[en] The Isochronous Mass Spectrometry (IMS) allows to measure masses of rare exotic nuclei in a storage ring in a timescale of tens of μs. The ring is operated in an isochronous mode, i.e. such that particles with different velocities but same mass-to-charge ratio (m/q) travel different paths in the ring arcs (faster ions travel longer paths whereas slower ions travel shorter paths). This means that for each m/q a fix revolution time exists and can be measured by a time-of-flight (TOF) detector which then yields the masses of the nuclei for known charge states. A new analysis approach of IMS data with a correlation matrix method allowed combining data with different quality. The latest production run was using an additional determination of the magnetic rigidity which increased the resolving power of the experiment. Combining this experiment with previous experiments one can increase the statistics and accuracy of the overall mass determination. It was possible to deduce mass values of neutron rich isotopes which have not been measured before. One of those isotopes is "1"3"0Cd which is a very important nuclei involved in the r-process. Those mass values and a comparison to theoretical predictions will be presented in the poster.
[en] The theoretical models of the cluster structures of the light neutron-rich nuclei as well as the corresponding physical mechanism and experimental approaches by breakup reaction have been introduced,which may serve as references for possible experimental studies of the cluster structure of light neutron-rich nuclei. (authors)
[en] State-of-the-art precision measurements on radioactive ions have been performed with the Penning-trap mass spectrometer ISOLTRAP at CERN. Minute production rates often accompanied by huge isobaric background and millisecond half-lives pose enormous challenges on the experimental setup and often require new experimental techniques. The ISOLTRAP setup has recently been enhanced with an electrostatic mirror ion trap acting as a multi-reflection time-of-flight mass separator (MR-ToF MS) for beam purification. It can likewise be used as a spectrometer in combination with a suitable detector increasing the mass-measurement capability of ISOLTRAP considerably. The measurements on the calcium isotopic chain will be presented together with the nuclear structure they reveal. The measurements up to 54Ca are compared with predictions from models that utilize three-body nuclear forces.