E-Print Archive

There are 4290 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
* News 04/04/20 * The archive is using a new backend database. This has thrown up a few SQL errors in the last few days. If you have any issues please email adavey@nso.edu with either the number of eprint you are trying to edit or a link to your preprint.

Comparing Values of the Relative Magnetic Helicity in Finite Volumes View all abstracts by submitter

Gherardo Valori   Submitted: 2012-02-13 08:59

Relative magnetic helicity, as a conserved quantity of idealmagnetohydrodynamics,has been highlighted as an important quantity to study inplasma physics. Due to its non-local nature, its estimation is notstraightforwardin both observational and numerical data. In the present study wederive expressionsfor the practical computation of the gauge-independent relative magnetichelicity in three-dimensional finite domains. The derived expressionsare easyto implement and rapid to compute. They are derived in Cartesiancoordinates,but can be easily written in other coordinate systems. We apply ourmethod to anumerical model of a force-free equilibrium containing a flux rope,and comparethe results with those obtained employing known half-space equations.We findthat our method requires a much smaller volume than half-spaceexpressionsto derive the full helicity content. Additionally, we prove thatvalues of relativemagnetic helicity of different magnetic fields can be compared witheach otherin the same sense as free-energy values can. Therefore, relativemagnetic helicitycan be meaningfully and directly compared between different datasets,such asthose from different active regions, but also the same dataset atdifferent times.Typical applications of our formulae include the helicity computationin threedimensionalmodels of the solar atmosphere, e.g. coronal-field reconstructions byforce-free extrapolation and discretized magnetic fields of numericalsimulations.

Authors: Valori, G., Demoulin, P., Pariat E.

Publication Status: Solar Phys (accepted)
Last Modified: 2012-02-17 05:38
Go to main E-Print page  Speeds and arrival times of solar transients approximated by self-similar expanding circular fronts  Kinematics and helicity evolution of a loop-like eruptive prominence  Edit Entry  Download Preprint  Delete Entry 

Go to main E-Print pageGo to main E-Print page.
Previous AbstractPrevious Abstract.
Next AbstractNext Abstract.
Download PreprintDownload Preprint.
Submitter's HomepageSubmitters Homepage.
Edit EntryEdit Entry.
View All Abstracts By SubmitterView all abstracts by submitter.
Delete AbstractDelete abstract.

Latest Entries
Proper Orthogonal and Dynamic Mode Decomposition of Sunspot Data.
Statistical Properties of Superflares on Solar-type Stars: Results Using All of the Kepler Primary Mission Data
Turbulent viscosity and effective magnetic Prandtl number from simulations of isotropically forced turbulence
Time and Charge-Sign Dependence of the Heliospheric Modulation of Cosmic Rays
Bayesian Analysis of Quasi-periodic Pulsations in Stellar Flares
Cause and Kinematics of a Jetlike CME
The role of small-scale surface motions in the transfer of twist to a solar jet from a remote stable flux rope
Sub-second time evolution of Type III solar radio burst sources at fundamental and harmonic frequencies
Magnetically coupled atmosphere, fast sausage MHD waves, and forced magnetic field reconnection during the SOL2014-09-10T17:45 flare
Differential rotation of the solar corona: A new data-adaptive multiwavelength approach
Magnetic Helicity Flux across Solar Active Region Photospheres: I. Hemispheric Sign Preference in Solar Cycle 24
Seismological constraints on the solar coronal heating function
The Coronal Global Evolutionary Model: Using HMI Vector Magnetogram and Doppler Data to Determine Coronal Magnetic Field Evolution
Radio and X-ray Observations of Short-lived Episodes of Electron Acceleration in a Solar Microflare
Research progress based on observations of the New Vacuum Solar Telescope
Dynamics evolution of a solar active-region filament from quasi-static state to eruption: rolling motion, untwisting motion, material transfer, and chirality
Microwave Study of a Solar Circular Ribbon Flare
Precise Formation-Flying Telescope in Target-Centric Orbit: the Solar Case
Propagation Effects in Quiet Sun Observations at Meter Wavelengths
Twin Null-Point-Associated Major Eruptive Three-Ribbon Flares with Unusual Microwave Spectra

Related Pages
MSU Solar Physics.
Max Millennium Science Mail Archive.
Max Millennium Message of the Day Mail Archive.
Max Millennium Flare Catalog

Archive Maintainer
Alisdair Davey

© 2000-2020 Solar Physics Group - Montana State University