Quantitative analysis of an ECR Ar plasma structure by X-ray spectroscopy at high spatial resolution

Abstract

In the frame of the PANDORA_Gr3 project, aiming at measuring for the first time in-plasma nuclear β-decays of astrophysical interest, an innovative multi-diagnostic approach to correlate plasma parameters to nuclear activity has been proposed [1–3]. This is based on several detectors and techniques (optical emission spectroscopy, RF systems, interferopolarimetry) and here we focus on high resolution spatially-resolved X-ray spectroscopy, performed by means of a X-ray pin-hole camera setup sensitive in the 0.5–20 keV energy domain. We present measurements on an Ar plasma heated by Electron Cyclotron Resonance at the ECR-plasma lab of ATOMKI-Debrecen. The achieved spatial and energy resolution were 0.5 mm and 300 eV at 8 keV, respectively [4]. The new algorithm of analysis for single-photon-counted images has been developed allowing an investigation in High-Dynamic-Range (HDR) mode. Hence a spatially resolved quantitative characterization of plasma vs. plasma walls emitted spectra was done; the investigated electrons are the ones crucial for in-plasma ionization. Both stable and turbulent plasma regimes can be investigated.