E-Print Archive

There are 3977 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
The Heating of the Solar Corona View all abstracts by submitter

Eric R Priest   Submitted: 2000-01-11 11:03

One of the paradigms about coronal heating has been the belief that the mean or summit temperature of a coronal loop is completely insensitive to the nature of the heating mechanisms. However, we point out that the temperature profile along a coronal loop is highly sensitive to the form of the heating. For example, when a steady-state heating is balanced by thermal conduction, a uniform heating function makes the heat flux a linear function of distance along the loop, while T7/2 increases quadratically from the coronal footpoints; when the heating is concentrated near the coronal base, the heat flux is small and the T7/2 profile is flat above the base; when the heat is focussed near the summit of a loop, the heat flux is constant and T7/2 is a linear function of distance below the summit. This realisation may act as an incentive to proponents of particular heating mechanisms to determine how the heat deposition varies spatially within coronal structures such as loops or arcades and to observers to deduce the temperature profiles with as low an error as possible. We therefore propose a new two-part approach to try and solve the coronal heating problem, namely first of all to use observed temperature profiles to deduce the form of the heating, and secondly to use that heating form to deduce the likely heating mechanism. In particular, we apply this philosophy to a preliminary analysis of Yohkoh observations of the large-scale solar corona. This gives strong evidence against heating concentrated near the loop base for such loops and suggests that heating uniformly distributed along the loop is slightly more likely than heating concentrated at the summit. The implication is that large-scale loops are heated in situ throughout their length, rather than being a steady response to low-lying heating near their feet or at their summits. Unless waves can be shown to produce a heating close enough to uniform, the evidence is therefore at present for these large loops more in favour of turbulent reconnection at many small randomly-distributed current sheets, which is likely to be able to do so. In addition, we address briefly the questions: why does the coronal intensity reduce by a factor of 100 from solar maximum to solar minimum; why is the temperature maximum in large-scale closed regions about 2.3 MK at an altitude 1.5 Rodot; and why are the corresponding values in coronal holes about 1.5 MK and 1.5 Rodot?

Authors: E. R. Priest, C. R. Foley, J. Heyvaerts, T.D. Arber$^{*}$, D. Mackay$^{*}$, J. L. Culhane$^{+}$ and L.W. Acton

Publication Status: Ap J (submitted)
Last Modified: 2000-01-11 11:03
Go to main E-Print page  Exact Solutions for Reconnective Magnetic Annihilation
  Aspects of 3D Magnetic Reconnection
  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
Energy transport and heating by torsional Alfvén waves propagating from the photosphere to the corona in the quiet Sun
A Two-Step Magnetic Reconnection in a Confined X-class Flare in Solar Active Region 12673
Lifetimes and Emergence/Decay Rates of Star Spots on Solar-type Stars Estimated by Kepler Data in Comparison with Those of Sunspots
IRIS and SDO Observations of Solar Jetlets Resulting from Network-edge Flux Cancelation
Si IV Resonance Line Emission During Solar Flares: Non-LTE, Non-equilibrium, Radiation Transfer Simulations
Study of current sheets in the wake of two crossing filaments eruption
Quasi-periodic fast propagating magnetoacoustic waves during the magnetic reconnection between solar coronal loops
Spectroscopic EUV observations of impulsive solar energetic particle event sources
CME-driven shock and Type II solar radio burst band-splitting
Signatures of magnetic reconnection at the footpoints of fan shape jets on a light bridge driven by photospheric convective motions
Drifting of the line-tied footpoints of CME flux-ropes
Three-dimensional Magnetic Reconnection Triggering an X-class Confined Flare in Active Region 12192
Oscillations accompanying a He I 10830 Å negative flare in a solar facula
The Origin of Major Solar Activity - Collisional Shearing Between Nonconjugated Polarities of Multiple Bipoles Emerging Within Active Regions
Probing the Puzzle of Behind-the-limb γ-Ray Flares: Data-driven Simulations of Magnetic Connectivity and CME-driven Shock Evolution
Transition-region explosive events produced by plasmoid instability
Flare Productivity of Major Flaring Solar Active Regions: A Time-series Study of Photospheric Magnetic Properties
Physical processes involved in the EUV "Surge" Event of 09 May 2012
Formation and Eruption of an Active Region Sigmoid. II. Magnetohydrodynamic Simulation of a Multistage Eruption
Evolution of Photospheric Vector Magnetic Field Associated with Moving Flare Ribbons As Seen By GST

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