Observation of Blobs and Holes in the Boundary Plasma of EAST Tokamak

Intermittent convective transport at the edge and in the scrape-off layer(SOL)ofEAST was investigated by using fast reciprocating Langmuir probe.Holes,as part of plasmastrTictures,were detected for the first time inside the shear layer.The amplitude probabilitydistribution function of the turbulence is strongly skewed,with positive skewed events("blobs")prevailing in the SOL region and negative skewed events("holes")dominant inside the shearlayer.The statistical properties coincide with previous observations from JET.The generationmechanism of blobs and holes is also discussed.In addition burst structure and dynamics characterof them are also presented.