Abstract
A soft X ray (SXR) imaging system for diagnosing magnetic islands of a reversed field pinch (RFP) plasma is proposed. The SXR imaging system utilizes a microchannel plate (MCP) to record a higher-resolution distribution of two-dimensional (2D) luminosity on a phosphor plate. In order to identify the structure of the magnetic island from the obtained SXR image, we have calculated the 2D image expected from RFP plasmas. It is found that the 2D image reflects the change in the radiation intensity caused by the magnetic island. Also, the magnetic island can be distinguished clearly when the radiation power emitted from the magnetic island is more than about 20 % of that on the magnetic axis of RFP. Regarding with the view angle α of the SXR imaging system, the magnetic island due to a tearing mode on the m = 1/n = 8 rational surface can be detected as far as α > π/10.
