Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English   Periodicity: 4 times per year   Open access peer reviewed journal

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F. Herrnegger<sup>1

1</sup>Max-Planck Institut für Plasmaphysik, IPP-EURATOM Association, Garching bei München, Germany

Abstract: One aspect of the optimization concept of stellarators is the reduction of the normalized Pfirsch-Schlüter current density {j_∥² / j_⊥²}^1/2 to a reasonable level but obeying other side conditions, e.g., concerning small bootstrap currents, good stability properties, reasonable aspect ratio, etc. This problem is addressed in the present work. Various stellarator vacuum field are given analytically for M = 2, 3, 5, 10, 12 (M is the number of field periods around the torus) where the PS-current density is reduced by more than a factor of ten to rather small values around 0.3 even at small į-values.

1. Wobig H. The Theoretical Basis of a Drift-Optimized Stellarator Reactor. Plasma Phys. Control. Fusion 35 (1993) 903. https://doi.org/10.1088/0741-3335/35/8/001

2. Nührenberg J., W. Lotz, P. Merkel, C. Nührenberg, U. Schwenn, E. Strumberger. Overview on Wendelstein 7-X Theory. Transact. Fus. Technol. 27 (1995) 71. https://doi.org/10.13182/FST95-A11947048

3. Contributions to Wendelstein 7-X and Helias Reactor 1991 - 1998 (F. Herrnegger, F. Rau, H. Wobig, Eds., Report IPP 2/343, Feb. 1999, 607 pp., Max-Planck-Institut für Plasmaphysik, Garching, Germany).

4. Dommaschk W. Finite Field Harmonics for Stellarators with Improved Aspect Ratio. Z. Naturforsch. A 37 (1982) 867. https://doi.org/10.1515/zna-1982-0820

5. Dommaschk W. Representations for Vacuum Potentials in Stellarators. Comput. Phys. Comm. 40 (1986) 203. https://doi.org/10.1016/0010-4655(86)90109-8