$^{80}$Se(n,$\gamma$) cross-section measurement at CERN n_TOF

Radiative neutron capture cross section measurements are of fundamental importance for the study of the slow neutron capture (s-) process of nucleosynthesis. This mechanism is responsible for the formation of most elements heavier than iron in the Universe. Particularly relevant are branching nuclei along the s-process path, which are sensitive to the physical conditions of the stellar environment. One such example is the branching at $^{79} \mathrm{Se}$ (3.27 × $10^{5}$ y), which shows a thermally dependent β-decay rate. However, an astrophysically consistent interpretation requires also the knowledge of the closest neighbour isotopes involved. In particular, the $^{80} \mathrm{Se}$(n,γ) cross section directly affects the stellar yield of the “cold” branch leading to the formation of the s-only $^{82} \mathrm{Kr}$ Experimentally, there exists only one previous measurement on $^{80} \mathrm{Se}$ using the time of flight (TOF) technique. However, the latter suffers from some limitations that are described in this presentation. These drawbacks have been significantly improved in a recent measurement at CERN n TOF. This contribution presents a summary of the latter measurement and the status of the data analysis.