TJ-K

The TJ-K device is a torsatron (stellarator) with a single helical coil (l=1, m=6).

History

TJ-K was originally named TJ-IU, and was constructed at CIEMAT in Madrid, Spain. TJ-IU was taken into operation in 1994, and was operated at relatively high magnetic field (0.5 T) and heating power (200 kW of ECRH heating), and corresponding relatively high values of the plasma parameters (electron density: 5 × 10¹⁸ m^-3).

In 1999, TJ-K was transferred to Kiel, Germany (hence the 'K'), and in 2005 to the IGVP institute in Stuttgart, Germany. In its reincarnation as TJ-K, the device is operated at low magnetic field (about 0.07 T) and heating (1-6 kW of ECRH heating), and corresponding relatively low values of the plasma parameters (electron density: 5 × 10¹⁷ m^-3; electron temperature: 10 eV; ion temperature: 1 eV).

Diagnostics

Passive diagnostics

• Bolometry
• Fast camera
• Magnetics
• Spectroscopy

Active diagnostics

• Interferometry
• Langmuir/Mach Probes
• Laser-induced fluorescence

Current status

Dense Langmuir probe arrays. The outer port array (OPA, photograph on the left) is installed at the outer port O2 and O3, the top port array (TPA, photograph on the right) is successively installed at the top ports T5, T2 and T4.

Some research results can be found in the cited papers.

One of the remarkable diagnostics of TJ-K is a dense array of Langmuir probes, allowing detailed studies of turbulence.