E-Print Archive

There are 4354 abstracts currently viewable.


Search:

Advanced Search
Options
Main Page Add New E-Print Submitter
Information
Feedback
News Help/FAQ About Preferences
Manage Key Phrase
Notification
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.
Projects:

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 

Key
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
Energy budget of plasma motions, heating, and electron acceleration in a three-loop solar flare
Space weather: the solar perspective - an update to Schwenn (2006)
Mixed properties of slow magnetoacoustic and entropy waves in a plasma with heating/cooling misbalance
The morphology of average solar flare time profiles from observations of the Sun's lower atmosphere
Indications of stellar coronal mass ejections through coronal dimmings
Could switchbacks originate in the lower solar atmosphere? II. Propagation of switchbacks in the solar corona
Solar large-scale magnetic field and cycle patterns in solar dynamo
Three-dimensional magnetic reconnection in astrophysical plasmas
Energy partition in a confined flare with an extreme-ultraviolet late phase
Alfvén wave heating in partially ionized thin threads of solar prominences
He I 10830 Dimming During Solar Flares, I: The Crucial Role of Non-Thermal Collisional Ionisations
Separating aa-index into Solar and Hale Cycle Related Components Using Principal Component Analysis
Inward Propagating Plasma Parcels in the Solar Corona: Models with Aerodynamic Drag, Ablation, and Snowplow Accretion
Energetics and 3-D Structure of Elementary Events in Solar Coronal Heating
Stellar Superflares Observed Simultaneously with Kepler and XMM-Newton
Medium-term predictions of F10.7 and F30 cm solar radio flux with the adaptive Kalman filter
Resonances in a Coronal Loop Driven by Torsional Alfvén Waves Propagating from the Photosphere
Effects of external flow on resonant absorption of coronal loop kink oscillations driven by an external fast wave: Selective excitation problem
Emerging Dimming as Coronal Heating Episodes
Proxy-Based Prediction of Solar Extreme Ultraviolet Emission using Deep Learning

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