Time-of-flight and activation experiments on Pm and Tm for astrophysics

Guerrero, C.*; Lerendegui-Marco, J.*; Domingo-Pardo, C.*; 原田 秀郎; 木村 敦; n_TOF Collaboration*; 他113名*

EPJ Web of Conferences, 146, p.01007_1 - 01007_4, 2017/09

https://doi.org/10.1051/epjconf/201714601007

The neutron capture cross section of several key unstable isotopes acting as branching points in the s-process are crucial for stellar nucleosynthesis studies, but they are very challenging to measure due to the difficult production of sufficient sample material, the high activity of the resulting samples, and the actual (n,) measurement, for which high neutron fluxes and effective background rejection capabilities are required. Capture cross section of Pm and Tm have been measured for time-of-flight measurements at the CERN n_TOF facility using the 19 and 185m beam lines. Activation experiments on the same Pm and Tm targets with a high-intensity 30 keV quasi-Maxwellian flux of neutrons will be performed using the SARAF accelerator and the Liquid-Lithium Target (LiLiT) in order to extract the corresponding Maxwellian Average Cross Section (MACS). The status of these experiments and preliminary results will be presented and discussed as well.