Visible spectroscopy of highly charged tungsten ions with the JET charge exchange diagnostic

Visible spectroscopy of highly charged tungsten ions with the JET charge exchange diagnostic

Visible spectroscopy of highly charged tungsten ions with the JET charge exchange diagnostic 150 150 Mathew
UKAEA-CCFE-PR(21)47

Visible spectroscopy of highly charged tungsten ions with the JET charge exchange diagnostic

Visible emission from a broad range of tungsten charge states has complicated plasma ion temperature and toroidal rotation measurements on the JET tokamak since the installation of the ITER-like wall. A plethora of charge exchange emission lines from ions up to W 56+ and 21 suspected magnetic dipole emission lines have so far been observed. In particular W 39+ and W 46+ charge exchange emission contaminates the long-established carbon measurement at 529nm. Fortunately the wavelength and relative intensity of the tungsten charge exchange lines is predictable and their influence can be mitigated when they are included in the spectral fit. Neon based charge exchange measurements at 525nm are now preferred on JET since the ITER-like wall, however in this case an unidentified tungsten magnetic dipole transition contaminates the spectrum when the electron temperature is low.

Collection:
Journals
Journal:
Physica Scripta
Publisher:
IOP (Institute of Physics)