TJ-II:Diagnostic neutral beam
TJ-II has a compact diagnostic neutral beam injector, designed for performing spatially resolved charge exchange recombination spectroscopy and neutral particle analysis measurements. It is located in sector A7 and it is currently employed to obtain radial profiles of impurity ion (carbon) temperature and velocity. [1] The injector, an upgraded DINA-5 model, is supported on a mobile cradle that permits its path through the plasma to be varied by ±3° poloidally. In parallel, a dedicated bidirectional (two vertical opposing views) multichannel spectroscopic diagnostic, incorporating fiber arrays, an f/1.8 spectrograph, and a back-illuminated charge-coupled device, has been installed to obtain Doppler line shifts and widths (around 529.2 nm) with ~1 cm spatial resolution. [2] [3]
The Diagnostic Neutral Beam Injector can also be used for Motional Stark Effect measurements to quantify the magnitude and pitch of components of the magnetic field[4].
See also
References
- ↑ K.J. McCarthy et al, Diagnostic neutral beam injector and associated diagnostic systems for the TJ-II stellarator device, Rev. Sci. Instrum. 75, 3499 (2004)
- ↑ J.M. Carmona et al, Charge-exchange spectroscopic diagnostic for the TJ-II stellarator, Rev. Sci. Instrum. 77, 10F107 (2006)
- ↑ J.M. Carmona et al, Density Dependence of Ion Temperature Measured by Active Charge-Exchange Spectroscopy in ECRH Plasmas of the TJ-II Stellarator, Fusion Science and Technology 54, 4 (2008) 962-969
- ↑ K. J. McCarthy, N. Panadero, A. López-Fraguas, J. Hernández, and B. van Milligen, A Spectrally Resolved Motional Stark Effect Diagnostic for the TJ-II Stellarator, Contrib. Plasma Phys. 55, No. 6 (2015) 459