Observation of the high-field-side high-density front in J-TEXT tokamak

Observation of the high-field-side high-density front in J-TEXT tokamak

Observation of the high-field-side high-density front in J-TEXT tokamak 150 150 Mathew
UKAEA-CCFE-PR(21)80

Observation of the high-field-side high-density front in J-TEXT tokamak

This article reports the first observation of the high-field side high density (HFSHD) in the limiter devices. In the J-TEXT high density discharges, the high-density front at the HFS scrape-off layer (SOL) region edge has been clearly identified by the far-infrared laser polarimeter-interferometer. The HFSHD forms at the HFS SOL, and then expands poloidally while propagates into main plasma region as the density further increasing. Usually, a well-developed HFSHD front is found to evolve from the stable state of staying at HFS edge to the dynamic state of moving poloidally, while approaching to density limit. In plasma current scanning experiments, it is found that both the density threshold of HFSHD formation and the maximum density of HFSHD itself increase with . In the relationship between  and HFSHD, edge parameters such as SOL collisionality (neL/Te2) and particle density, show crucial role.

 

Collection:
Journals
Journal:
Plasma Physics and Controlled Fusion
Publisher:
IOP (Institute of Physics)
Published date:
27/10/2021
The published version of this paper is currently under embargo and will be available on 27/10/2022