May 07, 2024
New Plasma Duration Record Set by WEST Tokamak

Equipped with superconducting coils and tungsten plasma-facing actively cooled components, the WEST tokamak has achieved a new plasma duration record of over 6 minutes, with a steady-state temperature of 50 million degrees Celsius (4 keV).

New Plasma Duration Record Set by WEST Tokamak

New Plasma record in WEST : 364 s and 1.15 GJ injected energy

The latest experimental campaign of WEST commenced in mid-January 2024 and concluded on April 26 after a four-month experimentation period.

During this campaign, a new plasma duration record of 6 minutes and 4 seconds was achieved, with an injected energy of 1.15 GJ, a steady-state central electron temperature of 4 keV (50 million degrees Celsius), and with an electron density twice that of discharges obtained in the tokamak's previous configuration, Tore Supra. The electron temperature was measured, notably through a new method developed by collaborators from the Princeton Plasma Physics Laboratory (PPPL). This new diagnostic can be used not only to measure electron temperature in the plasma but also the density of impurities, largely composed of tungsten eroded from the wall and migrated into the plasma core. Measuring and controlling the quantity of impurities are crucial for the operation of a tokamak in a metallic environment, as these impurities can cause rapid cooling of the plasma or even contribute to its sudden extinction.

New Plasma Duration Record Set by WEST Tokamak

WEST Plasma with "X -point radiator"

In addition to the plasma duration record, the latest experimental campaign made progress in other areas. The "X-Point radiation" plasma scenario was explored, leading to the achievement of one-minute plasmas with low electron temperature (Te < 5 eV) in the divertor. These radiating plasmas allow for a better distribution of heat fluxes on the plasma-facing components, significantly improving their lifespan. Several new diagnostics, some developed and installed by international collaborators, were successfully deployed, providing new measurements to characterize core and edge plasma. New records for power injection systems were also achieved, with 5.8 MW injected by the lower hybrid heating and current drive system and over 4 MW by the ion cyclotron resonance heating system. The latter system was also used to study a method for conditioning the tokamak walls, a method envisaged for ITER tokamak wall conditioning.


Finally, during this campaign, WEST surpassed the milestone of 10,000 plasmas since the first one was achieved in December 2016.

The tokamak is now in a shutdown period for maintenance and to install new systems. The next experimental campaign will commence in the autumn of this year.

New Plasma Duration Record Set by WEST Tokamak

Inside of WEST tokamak with Iter-grade plasma facing components

Last update : 05/07 2024 (944)