Dra. Susana Cebrían – Quantification and control of the cosmogenic activation of materials

Experiments devoted to investigate rare events, like the direct detection of galactic dark matter particles, neutrino interactions or nuclear double beta decays, demand ultra-low background conditions. Many different strategies are applied to suppress or mitigate all the background components entangling the expected signals. Long-lived radioisotopes produced by the exposure of materials to cosmic rays on the Earth’s surface can become problematic for the required sensitivity.

In this seminar, the origin of this cosmogenic activation will be presented and the ways to quantify the activation yields following different approaches. Precise quantification is important to assess the real danger of this background source and to take accordingly the necessary actions for production, transport and storage of materials. Finally, examples of cosmogenic activation studies relevant for underground experiments will be shown, considering detector target materials (like Ge, NaI, Xe or Ar) or other ones commonly used (like Cu, Pb or stainless steel).