Application of soft X-ray imaging system to the STE-2 RFP

A soft X-ray (SXR) imaging system (consisting of a microchannel plate, a phosphor plate and an image intensifier CCD camera) has been installed in the STE-2 RFP (R/a=0.4 m/0.1 m) to obtain high-resolution two-dimensional (2-D) SXR images to see if 3-D magnetic structures can be deduced from the 2-D SXR image. The SXR images obtained in standard RFP plasmas have been compared with those in RFP plasmas with different MHD properties. We have identified characteristic structures in the 2-D SXR images depending upon the MHD properties with the present system. Optimization of the image data processing such as noise filtering from the data or tone correction of brightness distribution is also discussed. (author)