2017 Volume 12 Pages 1202007
The density fluctuation was measured with a 70-GHz microwave interferometry system in the linear divertor plasma simulator NAGDIS-II while changing from the attached to the detached states. In the detached plasma, a large amplitude fluctuation of ≤ 10 kHz appeared in the peripheral region. The fluctuation has a maximum value at the neutral gas pressure of 30 - 34 mTorr. Further, the measurement of the light emission associated with the plasma recombination indicates that the large amplitude fluctuation is located at just downstream of the recombination front, in which the recombination process is the most enhanced.
