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Title: Magnetic axis safety factor of finite β spheromaks and transition from spheromaks to toroidal magnetic bubbles

Journal Article · · Physics of Plasmas
DOI:https://doi.org/10.1063/1.4908553· OSTI ID:22408108
 [1];  [2]
  1. Applied Physics and Materials Science, Caltech, Pasadena, California 91107 (United States)
  2. Consorzio RFX and Istituto Gas Ionizzati del C.N.R, Corso Stati Uniti, 4 35127 Padova (Italy)

The value of the safety factor on the magnetic axis of a finite-beta spheromak is shown to be a function of beta in contrast to what was used in Bellan, Phys. Plasmas 9, 3050 (2002); this dependence on beta substantially reduces the gradient of the safety factor compared to the previous calculation. The method for generating finite-beta spheromak equilibria is extended to generate equilibria describing toroidal magnetic “bubbles,” where the hydrodynamic pressure on the magnetic axis is less than on the toroid surface. This “anti-confinement” configuration can be considered an equilibrium with an inverted beta profile and is relevant to interplanetary magnetic clouds as these clouds have lower hydrodynamic pressure in their interior than on their surface.

OSTI ID:
22408108
Journal Information:
Physics of Plasmas, Vol. 22, Issue 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
Country of Publication:
United States
Language:
English