Fusion Science and Technology / Volume 51 / Number 2T / February 2007 / Pages 259-261
Technical Paper / Open Magnetic Systems for Plasma Confinement
The development and optimization of the fueling method enable us to increase and sustain the plasma density. In the present plasma experiments, three major ways, which are gas puff, NBI and pellet injection, are used for particle supply to keep or increase the plasma density. In the GAMMA 10 tandem mirror, the study of particle fueling has been carried out in term of high performance plasma production. In the central cell of GAMMA 10, a pellet injector, a neutral beam injector and some gas puffers have been installed. To clarify the feature of particle fueling method and compare with each other, the calculation with simple slab model is applied to the experimental results, and the effects of the particle fueling method on the plasma parameters are compared experimentally. As the results, it is found that the change of the electron density and H line emission profiles caused by pellet injection has the peak near the center of the plasma and the change of the density and temperature occurs quickly. The change of the plasma parameters caused by the gas puff mainly occurs in the peripheral region of the injection side. And the change of the plasma profiles occurs in core region of the plasma and the plasma temperature is sustained during several ms when the particles are fueled by the neutral beam injection.