E-Print Archive

There are 4099 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
Photospheric Motions and Coronal Mass Ejection Productivity View all abstracts by submitter

Alexander Nindos   Submitted: 2002-06-28 00:35

Shearing motions have been frequently used in MHD simulations of CME initiation but have hardly been reported from observations of CME-producing regions. In this paper we investigate whether the bulk of magnetic helicity carried away from the Sun by CMEs comes from helicity injected to the corona by such motions or by emerging magnetic flux. We use photospheric magnetic field observations of active region NOAA 9165 (AR 9165) which is an ideal candidate for such study because (1) it is the site of both new flux emergence and intense horizontal shearing flows; (2) it shows rapid development and rapid decay and for a few days it is the site of violent activity; (3) the horizontal motions occur when it is close to disk center, thus minimizing the errors involved in the relevant computations; (4) observations of a magnetic cloud associated with one of the CMEs linked to the active region are available. The computed helicity change due to horizontal shearing motions is probably the largest ever reported; it amounts to about the total helicity that the active region's differential rotation would have injected within 3 solar rotations. But the CMEs linked to the active region remove at least a factor of 4-64 more helicity than the helicity injected by horizontal shearing motions. Consequently the main source of the helicity carried away by the CMEs is the new magnetic flux that emerges twisted from the convective zone. Our study implies that shearing motions, even when they are strong, have little effect in the process of buildup of magnetic free energy that leads to the initiation of CMEs.

Authors: A. Nindos, H. Zhang
Projects:

Publication Status: ApJ, 573, L133
Last Modified: 2002-06-28 00:35
Go to main E-Print page  Damping Time Scaling of Coronal Loop Oscillations Deduced from TRACEObservations  Spatially resolved microwave oscillations above a sunspot  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
On the Origin of Solar Torsional Oscillations and Extended Solar Cycle
What Sets the Magnetic Field Strength and Cycle Period in Solar-type Stars?
Stereoscopic Observations of an Erupting Mini-filament Driven Two-Sided-Loop Jet and the Applications for Diagnosing Filament Magnetic field
Dynamic Processes of the Moreton Wave on 2014 March 29
Shock Heating Energy of Umbral Flashes Measured with Integral Field Unit Spectroscopy
Stealth Coronal Mass Ejections from Active Regions
Coronal Loop Scaling Laws for Various Forms of Parallel Heat Conduction
Structure of the transition region and the low corona from TRACE and SDO observations near the limb
Quantifying the relationship between Moreton-Ramsey waves and "EIT waves" using observations of 4 homologous wave events
Formation of quasi-periodic slow magnetoacoustic wave trains by the heating/cooling misbalance
Fundamental Transverse Vibrations of the Active Region Solar Corona
Damping of slow magnetoacoustic oscillations by the misbalance between heating and cooling processes in the solar corona
Magnetic helicity and eruptivity in active region 12673
Impulsive coronal heating from large-scale magnetic rearrangements: from IRIS to SDO/AIA
Probing the effect of cadence on the estimates of photospheric energy and helicity injections in eruptive active region NOAA AR 11158
The birth of a coronal mass ejection
Oscillations of the baseline of solar magnetic field and solar irradiance on a millennial timescale
Chromospheric cannonballs on the Sun
Magnetic Helicity from Multipolar Regions on the Solar Surface
Exoplanet predictions based on harmonic orbit resonances

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