Observation of new neutron-rich isotopesat the NSCL

摘要

Recently, increased primary beam intensities at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University and advances in experimental techniques allowed probing further into unknown regions of the table of the isotopes with fragmentation and in-flight fission reactions. Recent measurements at the NSCL have demonstrated that primary beams of ~(48)Ca at 141 MeV/u and ~(76)Ge at 132 MeV/u can be used to produce new isotopes ~(40)Mg, ~(42,43)Al, ~(44)si, ~(52)Ar, ~(50)Cl, ~(52,53)Ar, ~(55,56)K, ~(57,58)Ca, ~(59,60,61)Sc, ~(62,63)Ti, ~(65,66)V,~(68)Cr, ~(70)Mn in the proximity of the neutron dripline. Also, experiments with ~(238)U (81 MeV/u) and ~(208)Pb (86 MeV/u) beams in order to measure production yields and possibly observe several neutron rich isotopes in the first time have recently been performed at the NSCL. A search for new neutron-rich isotopes with ~(48)Ca and ~(76)Ge beams was carried out using the recently developed two-stage fragment separator technique.