Speaker
Description
The PANDORA (Plasmas for Astrophysics, Nuclear Decay Observation and Radiation for Archaeometry) project aims to establish a novel experimental facility at INFN-LNS (Catania) dedicated to interdisciplinary research on magnetically confined plasmas, with applications ranging from nuclear astrophysics to radiation sensor and detector testing.
The facility is designed to reproduce selected stellar thermodynamic conditions, particularly in terms of plasma temperature. A primary scientific objective is the first direct measurement of nuclear β-decay rates in hot plasmas. Both theoretical studies and experiments on fully stripped ions have demonstrated that β-decay lifetimes may vary by orders of magnitude in highly ionized environments. The PANDORA setup is based on a compact superconducting B-minimum magnetic trap, where plasmas of different elements are generated via Electron Cyclotron Resonance (ECR). The plasma parameters are expected to reach electron densities nₑ ≈ 10¹¹–10¹³ cm⁻³ and tunable electron temperatures Tₑ ≈ 0.1–30 keV. Under these conditions, the plasma emits intense RF, visible, UV, X-ray, and γ radiation. To fully characterize the plasma state and correlate it with nuclear decay measurements, PANDORA integrates a comprehensive multi-diagnostic system, including RF interferometry and polarimetry, optical and X-ray spectroscopy, X-ray imaging, and spatially resolved spectroscopy performed with different detector technologies. An array of 14 HPGe detectors will be employed to measure β-decay rates through high-resolution γ-ray spectroscopy, detecting the de-excitation photons emitted by the daughter nuclei. The decay rate will be monitored in real time and correlated with the simultaneously measured thermodynamic plasma parameters. The facility is currently under construction, with first plasma expected in late 2026. Beyond β-decay studies, the setup will enable additional astrophysically relevant experiments, such as laboratory measurements of optical opacities under conditions pertinent to r-process nucleosynthesis in kilonova scenarios. Among more than one hundred identified physics cases, the first experimental campaign will focus on a shortlist including ⁹⁴Nb (t₁/₂ ≈ 2 × 10⁴ y), 134Cs (t₁/₂ ≈ 2.5 y), and 176Lu (t₁/₂ ≈ 3.76 × 10¹⁰ y). The facility will also serve as an open platform for testing innovative technologies and methodologies relevant to plasma-based research and will be accessible to the broader scientific community.