Diagnostics for the Kstar: Korea Super-Conducting Tokamak Advanced Research

Abstract

The KSTAR (Korea Super-conducting Tokamak Advanced Research) [1,2] is aiming at the successful performance of the advanced tokamak (AT) mode and steady state operations. Though the AT mode can be realized in present tokamaks, it has usually been achieved as a transient phenomenon, shorter than the characteristic time scales. The KSTAR, however, will pursue steady state AT operation with fully super-conducting magnets and with state-of-the-art plasma control schemes. After achieving the first plasma milestone, the KSTAR operations for testing AT modes will be performed in order according to the availability of heating and other ancillary systems. KSTAR diagnostics are also installed in a phased manner, prioritized by the order of the operation scenarios, the availability of related technologies and the required time for development. The whole diagnostics set is classified in three categories as the Machine and Control, Core, and Divertor and Edge. The whole set is also listed in three phases by the order of development as Basic, Baseline and Mission-oriented. The Basic set consists of a minimal diagnostics for the Day One plasma operation of KSTAR. Most of magnetic diagnostics and relatively simple diagnostic sets for measuring basic parameters such as electron temperature and density, ion temperature, impurity behavior, neutral pressure, and run-away electron detection are included. Monitoring TV viewing inside vacuum vessel in the visible and IR region will also be included in this phase of development. As other ancillary systems are installed to KSTAR, relevant diagnostics is going to be added in parallel. Thus for the Baseline campaign when important physics experiments will be performed with intensive heating capabilities with a divertor configuration, profile measurements of important parameters should be provided. Baseline diagnostics are prepared for this purpose. Some diagnostics are still in consideration for development for KSTAR since they may not be urgent or technologies for their realization have not been evolved enough. The time for starting development of such diagnostics will be determined as the demands and necessities are raised along the way of KSTAR operation or as the technical problems are to be solved.