Development of design options for the port plug components of the ITER core CXRS diagnostic

The paper presents component concepts developed for the ITER core charge exchange recombination spectroscopy (cCXRS). They are based on the cCXRS layout of 2009, named as reference design option. It includes an outer shell, carrying a blanket shield module and a shielding cassette. The cassette, attached to the outer shell, carries secondary mirrors and a retractable tube. The tube holds a first mirror (M1) and a shutter. Development priority is given to the M1, M1 holder, shutter, calibration system and retractable tube. These units are the most critical from reliability point of view. The developed design approaches could be likely used as generic or prototype solutions for a cCXRS diagnostic port plug in future. Before prototyping critical components as the M1 holder and shutter, the final cCXRS conceptual design has to meet forthcoming changes in the ITER diagnostic upper port plug (UPP) and blanket system. The integrated first wall-diagnostic shield modules, first wall recession, blanket shaping and generic UPP layout have considerable impact on the layout of the cCXRS and its components. The paper presents a preliminary solution for integration of the customized reference cCXRS into expected ITER blanket and UPP layouts.