First application of the island divertor configuration in the J-TEXT tokamak

Abstract

For the first time, an island divertor configuration was successfully implemented in the J-TEXT tokamak to improve heat exhaust and impurity control. The magnetic island is generated by applying external resonant magnetic perturbation fields, and the intersection between the edge island and the divertor target is then controlled by adjusting the edge safety factor qa, thereby achieving the island divertor configuration. The overall confinement is maintained in spite of the loss of the edge volume. The island divertor configuration significantly reduces peak heat-load on the divertor target by approximately 50% and improves impurity screening. Additionally, it effectively modulates radiation around the magnetic island's X-point, potentially enhancing the stability and control of radiative divertor operations. These findings highlight the island divertor configuration as a promising strategy for advancing heat exhaust and impurity control in tokamak operations.