EAST tokamak plasma probe data

A movable multi-pin probe in Deuterium discharges in the superconducting EAST tokamak was used to recover local plasma parameters and electrostatic fluctuation characteristics along prescribed radial traverses. Several spatial regions are distinguished during the radial probe motion. The present analysis is restricted to a region inside the last closed magnetic flux surface, where locally homogeneous conditions can be argued. The data are analyzed with particular attention to the presence of cm-scale electrostatic plasma fluctuations. The detailed characteristics of the observed structures are described and quantified. Their contribution to anomalous plasma transport across magnetic field lines is demonstrated. Supported by correlation analyses, the primary analysis tool is conditional averaging, where the results are here presented with conditional variances included. Detailed information on properties of plasma blobs propagating across magnetic field lines is recovered. Alternative diagnostic methods are described and given analytic support. These tools can be applied when partial or reduced results suffice, offering also means of cross-checking basic fluctuation parameters. The agreement is good for the present plasma conditions.