Experimental Study Of The Edge Ion Temperature And Rotation Velocity On EAST Tokamak

For nuclear fusion plasma physics experiments,the ion temperature and rotation velocity are important parameters,they are also important for understanding plasma equilibrium,the transition from low confinement to higher confinement,and the instability of the pedestal structure.The Charge eXchange Recombination Spectroscopy(CXRS)is a commonly method for measuring plasma ion temperature and rotational velocity.Moreover,the boundary region ion temperature and rotation velocity are only given by the edge Charge eXchange Recombination Spectroscopy System.It has been successfully applied to many large-scale tokamak devices.Its diagnostic principle is through high-energy neutral beam particles collide with completely stripped electrons of the impurity ion charge exchange,then using impurity ions with photon information from the excited state transition to the lower energy level issued to diagnose.Doppler shift and Doppler broadening in photonic information can provide information on ion rotation speed and ion temperature,respectively.The CXRS system on EAST is briefly introduced in this paper,including layout,temporal and spatial resolution,and protection,and focuses on the EAST edge CXRS system.Including the whole system of the three calibration:wavelength calibration,spatial calibration and intensity calibration,and the relative sensitivity of the whole system and the filter used before the transmittance curve was calculated.At last,the physical phenomena of EAST tokamak are analyzed by the information of edge ion temperature and rotation velocity given by charge recombination exchange spectrum.The following conclusions are obtained respectively,1)The edge ion temperature and the rotation velocity transport barrier in the EAST high-confinement discharge were observed and found to be inconsistent with the prediction of the new classical theory.The results show that the shear instability caused by the toroidal velocity gradient has a great influence on the stability of the platform region,which affects the width of the pedestal.2)The H-mode shots and these shots edge toroidal velocity are statistically analyzed in the experiment.From the statistical data,it can be concluded at present,the plasma egde rotation has a dependency on the L-H transition threshold power and has the same result as other devices.The lower the boundary plasma toroidal rotation is,the lower the L-H transition threshold power is.In addition,the ion temperature and rotation velocity under the RMP,SMBI were also analyzed and the corresponding conclusions were drawn.