E-Print Archive

There are 4371 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
Phase Jumps in Local Helioseismology View all abstracts by submitter

Paul Cally   Submitted: 2008-11-08 13:25

Helioseismic rays trapped in a non-magnetic acoustic cavity suffer a +90 degree phase jump at their lower (Lamb) turning point and -90 degrees at the upper (acoustic cutoff) reflection point. That the two cancel allows local helioseismology to effectively assume that phase is continuous along a ray path joining two surface points. However, in strong surface magnetic field, as found in sunspots, we show - for an isothermal model with uniform magnetic field - that the phase jump for fast magnetoacoustic rays that penetrate the acoustic/Alfvénic equipartition level (c=a) is around -120 degrees. Moreover, there are further negative phase jumps on the upgoing and downgoing legs at c=a which add to the net phase change. Neglecting these effects can lead to a misinterpretation of helioseismic data in terms of travel-time shifts.

Authors: P. S. Cally
Projects: None

Publication Status: Solar Physics (accepted)
Last Modified: 2008-11-09 18:22
Go to main E-Print page  Numerical models of travel-time inhomogeneities in sunspots  Sixty-five years of solar radioastronomy: flares, coronal mass ejections and Sun-Earth connection  Edit Entry  Download Preprint  Submitter's Homepage 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
The Poissonian origin of power laws in solar flare waiting time distributions
Correlation of the sunspot number and the waiting time distribution of solar flares, coronal mass ejections, and solar wind switchback events observed with the Parker Solar Probe
Self-organized criticality in stellar flares
Finite system-size effectrs in self-organizing criticality systems
Global energetics of solar flares. XII. Energy scaling laws
Global energetics of solar flares. XI. Flare magnitude predictions of the GOES class
Are the Magnetic Fields Radial in the Solar Polar Region?
Fast magnetoacoustic wave trains: from tadpoles to boomerangs
Multi-channel coronal hole detection with convolutional neural networks
FOXSI-2 Solar Microflares. II. Hard X-ray Imaging Spectroscopy and Flare Energetics
Structure and Evolution of an Inter–Active Region Large-scale Magnetic Flux Rope
Variation of Magnetic Flux Ropes through Major Solar Flares
MHD Modeling of Solar Coronal Magnetic Evolution Driven by Photospheric Flow
The Causes of Peripheral Coronal Loop Contraction and Disappearance Revealed in a Magnetohydrodynamic Simulation of Solar Eruption
The Sun's Dynamic Extended Corona Observed in Extreme Ultraviolet
Magnetohydrodynamic Simulations of Spicular Jet Propagation Applied to Lower Solar Atmosphere Model
Thermal Trigger for Solar Flares II: Effect of the Guide Magnetic Field
The role of non-axisymmetry of magnetic flux rope in constraining solar eruptions
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)

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