Magnetic axis safety factor of finite β spheromaks and transition from spheromaks to toroidal magnetic bubbles
Abstract
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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2015
- Source ID
- 10.1063/1.4908553
Entities
People
- Paul M. Bellan
- Roberto Paccagnella
Organizations
- Air Force Office of Scientific Research
- California Institute of Technology
- National Science Foundation
- United States Department of Energy