Purpose:

The purpose of the NSTX Center Stack Upgrade (NSTX_CSU) project is to expand the NSTX operational space and thereby the physics basis for the next-step ST facilities. The plasma aspect ratio (ratio of major radius R₀ to minor radius a) of the upgrade is increased to 1.5 from the original value of 1.26, which increases the cross sectional area of the center stack by a factor of 3 and makes possible higher levels of performance and pulse duration. The new center stack will provide a toroidal magnetic field at the major radius R₀ of 1 Tesla (T) compared to 0.6T in the original NSTX device, and will enable operation at plasma current I_p up to 2 Mega-Amp (MA) compared to the 1MA rating of the original device. 

 

 

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