Nuclear Physics in Astrophysics VIII

Sub-barrier fusion cross section measurements with STELLA

20 Jun 2017, 19:30

2h

Sala conferenze (Laboratori Nazionali del Sud)

Poster Poster session

Speaker

Prof. Sandrine Courtin (IPHC Strasbourg)

Description

The STELLA (STELlar LAboratory) experimental station for the measurement of sub-barrier light heavy ion fusion cross sections has been commissioned at the Androm\`{e}de accelerator at IPN, Orsay. These measurements can yield both insight into nuclear cluster effects~[1] and the $S$-factors at energies of astrophysical interest. In particular, $^{12}$C+$^{12}$C fusion was identified as a key reaction on the production route of heavier elements in massive stars during the carbon burning phase, in type Ia supernovae and in superbursts from accreting neutron stars~[2]. Since sub-barrier fusion reactions are strongly hindered by Coulomb repulsion, the experimental determination of these cross sections ($\sim$~nb) is highly challenging. Nowadays, the determination of such cross sections is targeted with coincidence measurements using the so called gamma-particle-technique~[3]. The STELLA setup comprises a set of DSSSDs as well as an array of LaBr$_{3}$ detectors from the UK FATIMA collaboration (FAst TIMing Array) for charged particle and gamma recognition, respectively. In addition, a rotating target mechanism is developed to sustain beam intensities $>10\mu$A. In this contribution, the experimental layout will be introduced in detail with a focus on the design and performance of LaBr$_{3}$ detection array. Furthermore, the measurement technique will be sketched with first results from the commissioning campaign using $^{12}$C beam. [1] D.~Jenkins and S.~Courtin, Phys. Jour. G 42, 034010 (2015); [2] L.R.~Gasques \textit{et al.}, PRC 76, 3, 035802 (2007); [3] C.L.~Jiang \textit{et al.}, NIM A 682, 12 (2012);