EPJ A Highlight - Analysing Coulomb-excitation experiments with exotic beams

Details

Published on 25 April 2016

This paper presents a number of novel and alternative analysis techniques to extract transition strengths and quadrupole moments from Coulomb excitation data with Radioactive Ion Beams (RIBs) using the GOSIA code. It is anticipated that related approaches and techniques will gain an even greater importance as a wider range of post-accelerated RIBs becomes available at the next generation of ISOL facilities.

Indeed, recent advances in RIB technology, in particular the increasing range of species and post-acceleration energies available from ISOL facilities, have led to a resurgence of the use of nuclear reactions to study the structure of nuclei. Specifically, Coulomb excitation at safe energies, where the surfaces of the colliding nuclei are kept apart (typically 2-5 MeV/A), is now giving unrivalled information on the electromagnetic properties of exotic nuclei, leading to knowledge of the nuclear shape or, more precisely, the charge distribution of individual states. The usefulness of the technique to extract key nuclear-structure information has been demonstrated since the 1960's with stable beam and target combinations.

The paper addresses the situation where new challenges present themselves when studying exotic nuclei, including dealing with low statistics or number of data points, absolute and relative normalization of the measured cross sections and a lack of complementary experimental data, such as excited-state lifetimes, mixing and branching ratios.