ScholarLens Back to search
2013•Nuclear FusionOpen access

A new experimental classification of divertor detachment in ASDEX Upgrade

S. Potzel, M. Wischmeier, M. Bernert, R. Dux, H. W. Müller, A. Scarabosio, the ASDEX Upgrade Team

Open full text 155 citations

Abstract

In this paper, a new experimental classification of divertor detachment in ASDEX Upgrade is presented. For this purpose, a series of ohmic and L-mode density ramp discharges at different heating powers, magnetic field directions and plasma species were carried out. For the first time at ASDEX Upgrade the electron density in the divertor volume and the occurrence of volume recombination were measured by means of spectroscopy. It is shown that detachment is not a continuously evolving process but rather undergoes three distinct states while the characteristics of the inner and outer divertor are strongly coupled. Before the complete detachment of the inner and outer divertor, radiative fluctuations occur in the inner divertor close to the X-point, observed for the first time via new fast diode bolometers. Finally, the effect of an externally applied magnetic perturbation field on the detachment process is investigated.

About this research paper

What this paper is about

In this paper, a new experimental classification of divertor detachment in ASDEX Upgrade is presented. For this purpose, a series of ohmic and L-mode density ramp discharges at different heating powers, magnetic field directions and plasma species were carried out. For the first time at ASDEX Upgrade the electron density in the divertor volume and the occurrence of volume recombination were measured by means of spectroscopy. It is shown that detachment is not a continuously evolving process but rather undergoes three distinct states while the characteristics of the inner and outer divertor are strongly coupled. Before the complete detachment of the inner and outer divertor, radiative fluctuations occur in the inner divertor close to the X-point, observed for the first time via new fast diode bolometers. Finally, the effect of an externally applied magnetic perturbation field on the detachment process is investigated.

Why it matters

OpenAlex reports 155 citations for this work. Citation counts describe recorded attention and do not establish research quality.

Key contribution

A contribution statement is not available in the OpenAlex record.

Method / approach

Method details are not available in the OpenAlex metadata.

Main findings

Findings are not separately available in the OpenAlex metadata.

Limitations

Limitations are not available in the OpenAlex metadata.

Applications

Application details are not available in the OpenAlex metadata.

Available abstract

In this paper, a new experimental classification of divertor detachment in ASDEX Upgrade is presented. For this purpose, a series of ohmic and L-mode density ramp discharges at different heating powers, magnetic field directions and plasma species were carried out. For the first time at ASDEX Upgrade the electron density in the divertor volume and the occurrence of volume recombination were measured by means of spectroscopy. It is shown that detachment is not a continuously evolving process but rather undergoes three distinct states while the characteristics of the inner and outer divertor are strongly coupled. Before the complete detachment of the inner and outer divertor, radiative fluctuations occur in the inner divertor close to the X-point, observed for the first time via new fast diode bolometers. Finally, the effect of an externally applied magnetic perturbation field on the detachment process is investigated.

Key concepts: Divertor, ASDEX Upgrade, Plasma, Atomic physics, Magnetic field, Electron density, Electron temperature, Radiative transfer

Related papers

Related paper 1Related paper 2Related paper 3
Back to paper searchBrowse research topicsOriginal source
A new experimental classification of divertor detachment in ASDEX Upgrade — Research Paper | ScholarLens