Naselli, E.; Rácz, R.; Biri, S.; Mazzaglia, M.; Celona, L.; Gammino, S.; Torrisi, G.; Perduk, Z.; Galatà, A.; Mascali, D. Innovative Analytical Method for X-ray Imaging and Space-Resolved Spectroscopy of ECR Plasmas. Condens. Matter2022, 7, 5.
Naselli, E.; Rácz, R.; Biri, S.; Mazzaglia, M.; Celona, L.; Gammino, S.; Torrisi, G.; Perduk, Z.; Galatà, A.; Mascali, D. Innovative Analytical Method for X-ray Imaging and Space-Resolved Spectroscopy of ECR Plasmas. Condens. Matter 2022, 7, 5.
At INFN-LNS, and in collaboration with the ATOMKI laboratories, an innovative multi-diagnostic system with advanced analytical methods has been designed and implemented. This is based on several detectors and techniques (Optical Emission Spectroscopy, RF systems, Interfero-polarimetry, X-ray detectors) and here we focus on high resolution spatially-resolved X-ray spectroscopy, performed by means of a X-ray pin-hole camera setup operating in the 0.5−20 keV energy domain. The diagnostic system was installed at a 14 GHz Electron Cyclotron Resonance (ECR) ion source (ATOMKI, Debrecen), enabling high precision X-ray spectrally-resolved imaging of ECR plasmas heated by hundreds of Watts. The achieved spatial and energy resolution were 0.5 mm and 300 eV at 8 keV, respectively. We here present the innovative analysis algorithm that we properly developed for obtaining Single Photon-Counted (SPhC) images providing the local plasma emitted spectrum in a High-Dynamic-Range (HDR) mode, by distinguishing fluorescence lines of the materials of the plasma chamber (Ti, Ta) from plasma (Ar). This method allows a quantitative characterization of warm electrons population in the plasma (and its 2D distribution) which are the most important for ionization, and also to estimate local plasma density and spectral temperatures. The developed post-processing analysis is also able to remove the readout noise, that is often observable at very low exposure times (msec). The setup is now under update including fast shutters and trigger systems in order to allow simultaneously space and time-resolved plasma spectroscopy during transients, stable and turbulent regimes.
X-ray Imaging; Plasma Diagnostics; Electron Cyclotron Resonance Ion Sources; High Dynamical Range Analysis; Single-Photon-Counted Images; X-ray Spatially-resolved Spectroscopy
PHYSICAL SCIENCES, Fluids & Plasmas
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