The PANDORA project for in-plasma β-decay investigations of nuclear astrophysical interest

Thursday 21 May 2026, 16:30 → 17:30 Europe/Rome

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In the frame of the PANDORA (Plasmas for Astrophysics Nuclear Decays Observation and Radiation for Archaeometry) project, a new experimental approach has been conceived to measure, for the first time, in-plasma b-decays lifetimes as a function of thermodynamical conditions of the environment, namely a laboratory magnetized plasma able to mimic some stellar-like conditions. Theoretical models predict considerable variations in the β-decay lifetimes in highly ionized nuclides (e.g. by bound state b-decay), which would have a strong impact on stellar nucleosynthesis processes.

In the fully superconducting high performance PANDORA trap, a hot plasma containing a known concentration of β-decaying atoms can be confined and kept in dynamic equilibrium for weeks. The decay rate can be measured by detecting the γ-rays emitted by the daughter nuclei (through an array of 14 HPGe detectors) and correlated as a function of the average ionization state of radioactive ions using synergically an advanced plasma multi-diagnostic system.  PANDORA represents a promising experimental setup to verify, for the first time, the theoretical predictions on the dependence of lifetime on temperature and to investigate the expectations deriving from nucleosynthesis calculations. The sensitivity of the PANDORA setup was checked by estimating the duration of the experimental run to obtain sufficient statistical significance in terms of σ-confidence levels. The analysis was carried out for the first three physical cases (¹⁷⁶Lu, ¹³⁴Cs, ⁹⁴Nb) involved in crucial branching points in s-processing nucleosynthesis and selected according to the scientific relevance.

In this seminar, the PANDORA facility and the experimental approach will be described, along with the feasibility simulative studies and the plasma characterizations carried out on testbenches.