Speaker
Description
The lightest nuclei present physics problems where progress is only made incrementally and slowly. New instrumentation is then essential for further advances. We present here two examples taken from ISOLDE runs in 2016.
The first problem is motivated in the astrophysically very important 12C(a,g)16O reaction. The cross section of this reaction at energies relevant to stellar helium burning is still not known with sufficient accuracy. An important constraint comes from the beta-delayed alpha spectrum from 16N, but the litterature value of the absolute branching ratio has recently been questioned. The improvement in experimental sensitivity coming from the IDS set-up triggered a new experiment that was performed in May 2016. Preliminary results from this run will be presented.
The second long-standing problem is to understand the structure of the unbound nucleus 10Li and of the two-neutron halo nucleus 11Li. Earlier reaction experiments at REX-ISOLDE suffered from the limited energy available, the recent energy upgrade in HIE-ISOLDE clearly allows for more detailed investigations. As a first step the neutron transfer reaction from 9Li +2H to 10Li+p was performed in the Scattering Experiments Chamber (SEC) at the XT02 beam-line in November 2016. The one-neutron transfer to 9Li will populate excited states as well as low lying resonances in 10Li. The higher reaction energy gives better solid angle and angular coverage for charged particles, the set-up furthermore included for the first time a neutron detector array. The semi-permanent installation in the SEC at the XT02 beam line, which will be able to host many of the forthcoming scattering experiments at HIE-ISOLDE, will be described and preliminary data shown.
Finally, the continuation of these experiments will be briefly discussed.
