UAF Physics Department § Journal Club

Work done at Princeton Plasma Physics Laboratory (PPPL) in investigating local edge turbulence will be presented. Blob diffusion has been quantified using the D-alpha light intensity signal from GPI diagnostic on NSTX. In the moving reference frame of a blob, and assuming a general non-diffusive formulation, blob spreading can be best fitted to the diffusive model. From this, the spreading of an individual blob can then be quantified in terms of a spreading coefficient, which is analogous to a diffusion coefficient. Blobs in H-mode and Ohmic plasmas near the separatrix show distinguishing spreading coefficients. This segregation can be used to characterize blobs in different regimes and as a quantitative measure of the local dynamics for blobs across machines and between experiments and simulations.


	ABSTRACT Work done at Princeton Plasma Physics Laboratory (PPPL) in investigating local edge turbulence will be presented. Blob diffusion has been quantified using the D-alpha light intensity signal from GPI diagnostic on NSTX. In the moving reference frame of a blob, and assuming a general non-diffusive formulation, blob spreading can be best fitted to the diffusive model. From this, the spreading of an individual blob can then be quantified in terms of a spreading coefficient, which is analogous to a diffusion coefficient. Blobs in H-mode and Ohmic plasmas near the separatrix show distinguishing spreading coefficients. This segregation can be used to characterize blobs in different regimes and as a quantitative measure of the local dynamics for blobs across machines and between experiments and simulations.

	Friday, 4 March 2016
	Globe Room, Elvey Building
	3:45 PM