The PANDORA project: an experimental setup for measuring in-plasma β-decays of astrophysical interest

¹ INFN-Laboratori Nazionali del Sud, Catania, Italy
² INFN, Sezione di Perugia, Perugia, Italy
³ ENEA, Bologna, Italy
⁴ INFN, Sezione di Bologna, Italy
⁵ Universita degli Studi di Catania, Catania, Italy
⁶ INFN-Laboratori Nazionali di Legnaro, Legnaro (PD), Italy

Published online: 14 January 2020

Abstract

Experiments performed on Storage Rings have shown that lifetimes of beta-radionuclides can change dramatically as a function of theionization state. PANDORA (Plasmas for Astrophysics, Nuclear Decay Observation and Radiation for Archaeometry) aims at measuring, for the first time, nuclear β-decay rates in stellar-like conditions, especially for radionuclides involved in nuclear-astrophysics processes (BBN, s- processing, CosmoChronometers, Early Solar System formation). Compact magnetic plasma traps, where plasmas reach density n_e~10ⁿ-10¹⁴ cm^-3, and temperature T_e~0.1-30 keV, are suitable for such studies. The decay rates can be measured as a function of the charge state distribution of the inplasma ions. The collaboration is now designing the plasma trap able to reach the needed plasma densities, temperatures and charge states distributions. A first list of radioisotopes, including tens of physics cases of potential interest is now available. Possible physics cases include, among the others, ²°⁴Tl, ⁶³Ni, ⁶°Co, ¹⁷¹Tm, ¹⁴⁷Pm, ⁸⁵Kr, ¹⁷⁶Lu and the pairs ¹⁸⁷Re-¹⁸⁷Os and ⁸⁷Sr-⁸⁷Rb, which play a crucial role as cosmo-clock. Physics cases are now under evaluation in terms of lifetime measurements feasibility in a plasma trap.