Exploiting dissipative reactions to perform in-beam $\gamma$-ray spectroscopy of the neutron-deficient isotopes \nuc{38,39}{Ca}

TL;DR

This paper reports in-beam gamma-ray spectroscopy of neutron-deficient isotopes 38,39Ca, revealing higher-spin states and complex structures through dissipative reactions, providing new insights into their nuclear structure relevant for astrophysical processes.

Contribution

It introduces a novel approach using dissipative reactions to access complex-structure states in 38,39Ca, expanding spectroscopic information beyond lower-spin states.

Findings

Identification of higher-spin states in 39Ca

Observation of complex-structure states with small cross sections

Insights into nuclear structure relevant for astrophysics

Abstract

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 38,39 Ca 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 39 Ca populated in fast-beam-induced, momentum-dissipative processes leading to neutron pickup onto excited configurations of the projectile, 9 Be(38 Ca , 39 Ca + {\gamma})X. Such a dissipative reaction was recently characterized for the case of inelastic scattering of 38 Ca off 9 Be, 9 Be(38 Ca, 38 Ca + {\gamma})X. Additional data and discussion on the nuclear structure of 38 Ca 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.