Contribution to the multi-machine pedestal scaling from the COMPASS tokamak

Abstract

First systematic measurements of pedestal structure during Ohmic and NBI-assisted Type I ELMy H-modes were performed on the COMPASS tokamak in two dedicated experimental campaigns during 2015 and 2016. By adjusting the NBI heating and a toroidal magnetic field, the electron pedestal temperature was increased from 200 eV up to 300 eV, which allowed reaching pedestal collisionality < 1 at q95 ~3. COMPASS has approached conditions for the Identity experiment done at JET & DIII-D, complementing the range of scanned . The pedestal pressure was successfully reproduced by the EPED model. The dependence of pedestal pressure width on and is discussed.