Lyman line opacities in tokamak divertor plasmas under high-recycling and detached conditions
Year: 2024
Type: article
Abstract: Radiation transport simulations of the deuterium Lyman line series using EIRENE predict a factor of 2 increase of Balmer- α emission in the JET-ILW low confinement divertor plasmas in high-recycling and detached conditions caused by the re-absorption of Lyman- β emission. The photon tracing model in the EIRENE code is applied to SOLPS-ITER pure deuterium plasma solutions of JET-ILW to evaluate the contribution of Lyman- β capture towards the population density of D( p = 3 ) and, consequently, the Balmer- α emission. The local population escape factors of Lyman- α and Lyman- β lines in the JET-ILW divertor show steep spatial gradients and indicate local regions with high opacity in high-recycling and detached conditions. The relative contribution of Lyman- β capture towards the population density of D( p = 3 ) is significant in high-recycling and detached conditions. This observation is further corroborated by line-integrated calculations using Balmer- α diagnostic line-of-sights.
Source: Nuclear Materials and Energy
Institutions: Aalto University, Heinrich Heine University Düsseldorf, KU Leuven
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $434
Awards: G115085052, G1385120143, Implementation of activities described in the Roadmap to Fusion during Horizon Europe through a joint programme of the members of the EUROfusion consortium, G2293481551, Sensitivity-based uncertainty quantification for partially stochastic plasma edge simulations of nuclear fusion devices, G3562821882, G5172252545
OpenAlex ID: W4404117104