Potential Magnetic Field around a Helical Flux Rope Current Structure in the Solar Corona | Zendy

G. J. D. Petrie | Zendy

AI Assistant Blog Pricing

Home ZAIA Blog

Open Access

Potential Magnetic Field around a Helical Flux Rope Current Structure in the Solar Corona

Author(s) -

G. J. D. Petrie

Publication year - 2007

Publication title -

the astrophysical journal

Language(s) - English

Resource type - Journals

SCImago Journal Rank - 2.376

H-Index - 489

eISSN - 1538-4357

pISSN - 0004-637X

DOI - 10.1086/513456

Subject(s) - rope , physics , current sheet , magnetic flux , magnetic field , writhe , flux (metallurgy) , current (fluid) , field line , magnetic reconnection , solar prominence , kink instability , magnetohydrodynamics , coronal mass ejection , astrophysics , classical mechanics , twist , geometry , solar wind , quantum mechanics , materials science , structural engineering , engineering , metallurgy , thermodynamics , mathematics

We consider the potential magnetic field associated with a helical electricline current flow, idealizing the near-potential coronal field within which ahighly localized twisted current structure is embedded. It is found that thisfield has a significant axial component off the helical magnetic axis wherethere is no current flow, such that the flux winds around the axis. The helicalline current field, in including the effects of flux rope writhe, is thereforemore topologically complex than straight line and ring current fields sometimesused in solar flux rope models. The axial flux in magnetic fields aroundconfined current structures may be affected by the writhe of these currentstructures such that the field twists preferentially with the same handednessas the writhe. This property of fields around confined current structures withwrithe may be relevant to classes of coronal magnetic flux rope, includingstructures observed to have sigmoidal forms in soft X-rays and prominencemagnetic fields. For example, ``bald patches'' and the associated heating byParker current sheet dissipation seem likely. Thus some measurements of fluxrope magnetic helicities may derive from external, near-potential fields. Thepredicted hemispheric preference for positive and negative magnetic helicitiesis consistent with observational results for prominences and sigmoids and pasttheoretical results for flux rope internal fields.Comment: To appear in ApJ May 200

The content you want is available to Zendy users.

Already have an account? Click here to sign in.

Having issues? You can contact us here

Accelerating Research