The axial profile of Balmer-alpha emission near a tungsten target has been measured in the compact plasma wall interaction (PWI) simulator Advanced PWI Simulation Experimental Device and Analysis System (APSEDAS). Axial Hα emission decreases toward the target at two levels, a steep gradient within 10mm of the target and a shallow gradient more than 10mm away. The structure of the Hα profile within 40mm of the target is the same even though the electron density changes by one order of magnitude and the neutral pressure changes by a factor of three. On the other hand, the Hα profile more than 40mm from the target gradually increases with increasing hydrogen filling pressure, although it does not change with the density in the case of constant filling pressure.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics