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Recovery of the Electron Energy Distribution Function under Conditions of High-Power ECR Plasma Heating at the L-2M Stellarator

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Abstract

The electron energy distribution functions that form in the plasma heating region were recovered from data on the soft X-ray spectra in the energy range of 2−20 keV. The spectra were measured at the L-2M stellarator in the regime of electron cyclotron resonance (ECR) heating in two experiments: on the axial ECR heating (the heating power was PECRH = 250 kW, the electron density was ne = 1.9 × 1019 m–3, and the electron temperature was Te = 0.74 keV) and the off-axial ECR heating (PECRH = 350 kW, ne = 2.5 × 1019 m–3, and Te = 0.7 keV). It was shown that in both experiments the electron energy distribution functions are not Maxwellian and that considerable ensembles of suprathermal electrons form in the heating regions.

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Funding

The work was supported by the Russian Foundation for Basic Research (project no. 18-02-00609).

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Authors and Affiliations

  1. Prokhorov General Physics Institute, Russian Academy of Sciences, 119991, Moscow, Russia

    A. I. Meshcheryakov, I. A. Grishina & I. Yu. Vafin

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  1. A. I. Meshcheryakov
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  2. I. A. Grishina
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  3. I. Yu. Vafin
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Correspondence to A. I. Meshcheryakov.

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Meshcheryakov, A.I., Grishina, I.A. & Vafin, I.Y. Recovery of the Electron Energy Distribution Function under Conditions of High-Power ECR Plasma Heating at the L-2M Stellarator. Bull. Lebedev Phys. Inst. 48, 101–106 (2021). https://doi.org/10.3103/S1068335621040059

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  • DOI: https://doi.org/10.3103/S1068335621040059

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