Recurrence Plots for Dynamic Analysis of Type-I ELMs at JET With a Carbon Wall

• Published in: IEEE transactions on plasma science Vol. 47; no. 4; pp. 1871 - 1877
• Main Authors: Cannas, Barbara, Fanni, Alessandra, Murari, Andrea, Pisano, Fabio
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Carbon; Deuterium; Dynamic characteristics; Edge-localized modes (ELM); Electron density; ELM modeling; Joint European Torus; Plasma physics; Plasma temperature; Radiation; recurrence plots (RPs); Temperature; Time series; Time series analysis; Tokamak devices
• ISSN: 0093-3813; 1939-9375; 1939-9375
• DOI: 10.1109/TPS.2019.2901313

In this paper, the dynamic characteristics of type-I edge-localized modes (ELM) time series from the JET tokamak, the world's largest magnetic confinement plasma physics experiment, have been investigated through recurrence plots (RPs). The analysis has been focused on RPs of pedestal temperature, line averaged electron density, and outer divertor <inline-formula> <tex-math notation="LaTeX">D_{ {\alpha }} </tex-math></inline-formula> time series during experiments with a carbon wall. The analysis of RPS shows the patterns similar to those characteristics of signals exhibiting type-2 intermittency, in particular, a characteristic kite-like shape; this gives useful hints to model the temperature signal as well as the <inline-formula> <tex-math notation="LaTeX">D_{ {\alpha }} </tex-math></inline-formula> radiation time series, with simple nonlinear maps capturing the nearly periodic behavior of type-I ELMs.