Exploiting dissipative reactions to perform in-beam -ray spectroscopy of the neutron-deficient isotopes 38,39Ca

The neutron-deficient Ca isotopes continue to attract attention due to their importance for testing isospin symmetry and their relevance in capture reactions of interest for nova nucleosynthesis and the shape of light curves in Type I x-ray bursts. To date, spectroscopic information on 38,39Ca is largely limited to data on lower-spin excited states. Here, we report in-beam gamma -ray spectroscopy of complementary higher-spin, complex-structure states in 39Ca populated in fast-beam-induced, momentum-dissipative processes leading to neutron pickup onto excited configurations of the projectile, 9Be(38Ca*, 39Ca +gamma )X. Such a dissipative reaction was recently characterized for the case of inelastic scattering of 38Ca off 9Be, 9Be(38Ca, 38Ca +gamma )X. Additional data and discussion on the nuclear structure of 38Ca is also presented. An explanation for the more-complex-structure states, populated with small cross sections in one-nucleon knockout reactions, and observed in the tails of their longitudinal momentum distributions, is also offered.