Abstract
The investigations of the radial distributions of emission from the EXTRAP-T2 reversed-field pinch (RFP) plasma show that the emission profile varies a lot, even during one plasma discharge. At central electron temperatures of about 150 eV it was expected that the emission should emerge from the plasma centre. In comparison, is always observed to radiate from the centre. Our measurements of emission have, however, shown that this is not always the case, the emission often comes from the plasma edge. The analysis of the measurements has led us to conclude that the edge emission comes from charge-exchange recombination with neutral hydrogen near the carbon first wall. These observations provide a way to estimate the change in neutral hydrogen density during local plasma-wall interaction.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have