Magnetic Helicity from Multipolar Regions on the Solar Surface
arXiv:1804.04160 · doi:10.3847/1538-4357/aae97f
Abstract
The emergence of dipolar magnetic features on the solar surface is an idealization. Most of the magnetic flux emergence occurs in complex multipolar regions. Here, we show that the surface pattern of magnetic structures alone can reveal the sign of the underlying magnetic helicity in the nearly force-free coronal regions above. The sign of the magnetic helicity can be predicted to good accuracy by considering the three-dimensional position vectors of three spots on the sphere ordered by their relative strengths at the surface and compute from them the skew product. This product, which is a pseudoscalar, is shown to be a good proxy for the sign of the coronal magnetic helicity.
arXiv comment7 pages, 3 figures, 2 tables, published
References in corpus (20)
- Astrophysical magnetic fields and nonlinear dynamo theory
- Signature of Gravity Waves in Polarization of the Microwave Background
- A Probe of Primordial Gravity Waves and Vorticity
- The case for a distributed solar dynamo shaped by near-surface shear
- An Ab Initio Approach to the Solar Coronal Heating Problem
- Extension of the MURaM radiative MHD code for coronal simulations
- An Ab Initio approach to Solar Coronal Loops
- Intermittent heating in the solar corona employing a 3D MHD model
- Scale-dependence of magnetic helicity in the solar wind
- Origins of Rolling, Twisting and Non-Radial Propagation of Eruptive Solar Events
- Search for CP Violating Signature of Intergalactic Magnetic Helicity in the Gamma Ray Sky
- Observationally driven 3D MHD model of the solar corona above an active region
- Dynamo-driven plasmoid ejections above a spherical surface
- Intergalactic magnetic field spectra from diffuse gamma rays
- Primordial Magnetic Helicity Constraints from WMAP Nine-Year Data
- Probing magnetic helicity with synchrotron radiation and Faraday rotation
- Faraday signature of magnetic helicity from reduced depolarization
- Parity-odd correlators of diffuse gamma rays and intergalactic magnetic fields
- Magnetic twist: a source and property of space weather
- Magnetic Helicity Reversal in the Corona at Small Plasma Beta
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- A global two-scale helicity proxy from -ambiguous solar magnetic fields
- The Minimal Helicity of Solar Coronal Magnetic Fields
- On the measurement of handedness in Fermi Large Area Telescope data