E-Print Archive

There are 4035 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
A Note on Computation of Relative Magnetic Helicity Flux Across the Photosphere View all abstracts by submitter

Yang Liu   Submitted: 2012-12-19 09:07

A number of investigations of the rate of relative magnetic helicity transport across the photosphere [ dH/dt|S ] have reported differences in the estimates computed from two different formulations of the relative-helicity flux density proxy [ GA ] and [ G_theta ]. There have been suggestions that [ G_theta ] is a more robust helicity-flux density proxy and that the differences in the estimates of [dH/dt|S ] are caused by biases in [ GA ], noise, and/or the boundary conditions. In this note, we prove that the differences are caused by the inconsistent choice of boundary conditions in the explicit or implicit Green?s function [ G (x, x′) ] used for computing [ GA ] and [ G_theta ] when comparing the helicity flux estimates based on [ GA ] and [ G_theta ]. When the boundary conditions in [ G ] are chosen consistetently, the two helicity-flux density proxies, [ GA ] and [ G_theta ], produce essentially identical results for the rate of helicity transport across the photosphere. They also yield essentially identical results for the rate of helicity transport of the shearing and advection terms separately. Using MHD simulation, HMI observational data, and Monte Carlo simulations of noise we show that this result is robust. Neither the shape of the active region, nor the shape of the boundary, nor data noise causes any difference in the rate of helicity transport computed via [ GA ] and [ G_theta ].

Authors: Yang Liu, Peter W. Schuck
Projects: SDO-HMI

Publication Status: Solar Physics, Accepted.
Last Modified: 2012-12-19 12:09
Go to main E-Print page  Tracing Electron Beams in the Sun's Corona with Radio Dynamic Imaging Spectroscopy  Ejections of magnetic structures above a spherical wedge driven by a convective dynamo with differential rotation  Edit Entry  Download Preprint  Submitter's Homepage 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
Why Does the Solar Corona Abnormally Rotate Faster Than the Photosphere?
Impacts On Proton Fluxes Observed During Different Interplanetary Conditions
Coronal Loop Seismology Using Standing Kink Oscillations With a Lookup Table
Data-Optimized Coronal Field Model: I. Proof of Concept
Coronal Bright Points
Difference of source regions between fast and slow coronal mass ejections
Invited Review: Signatures of Magnetic Flux Ropes in the Low Solar Atmosphere Observed in High Resolution
Do Kepler superflare stars really include slowly-rotating Sun-like stars ? - Results using APO 3.5m telescope spectroscopic observations and Gaia-DR2 data -
Magnetically Induced Current Piston for Generating Extreme-ultraviolet Fronts in the Solar Corona
Magnetic Field Dynamics and Varying Plasma Emission in Large-scale Coronal Loops
Nonlinear Evolution of Ion Kinetic Instabilities in the Solar Wind
What determines the X-ray intensity and duration of a solar flare?
Fast Magnetoacoustic Wave Trains with Time-dependent Drivers
Three-dimensional reconstruction of CME-driven shock-streamer interaction from radio observations: a different take on the diagnostics of coronal magnetic fields
The soft X-ray spectrometer polarimeter SolpeX
Variable emission mechanism of a Type IV radio burst
Inference of magnetic field strength and density from damped transverse coronal waves
Frequency-Distance Structure of Solar Radio Sources Observed by LOFAR
The birth of a coronal mass ejection
Properties of slow magnetoacoustic oscillations of solar coronal loops by multi-instrumental observations

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



© 2003 Solar Physics Group - Montana State University