E-Print Archive

There are 4491 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
Torsional slow-mode oscillations discovered in the magnetic free energy during solar flares View all abstracts by submitter

Markus J Aschwanden   Submitted: 2020-01-27 15:08

We report the discovery of torsional Alfvénic oscillations in solar flares, which modulate the time evolution of the magnetic free energy E_f(t), while the magnetic potential energy E_p(t) is uncorrelated, and the nonpotential energy varies as Enp(t) = E_p + E_f(t). The mean observed time period of the torsional oscillations is Pobs=15.1 ± 3.9 min, the mean field line length is L=135±35 Mm, and the mean phase speed is vphase =315 ± 120 km s-1, which we interpret as torsional Alfvénic waves in flare loops with enhanced electron densities. Most of the torsional oscillations are found to be decay-less, but exhibit a positive or negative trend in the evolution of the free energy, indicating new emerging flux (if positive), magnetic cancellation, or flare energy dissipation (if negative). The time evolution of the free energy has been calculated in this study with the Vertical-Current Approximation (Version 4) Nonlinear Force-Free Field (VCA4-NLFFF) code, which incorporates automatically detected coronal loops in the solution and bypasses the non-forcefreeness of the photospheric boundary condition, in contrast to traditional NLFFF codes.

Authors: Aschwanden,M.J. and Wang,T.J.
Projects: None

Publication Status: ApJ (2020, Jan 27; in press)
Last Modified: 2020-01-29 13:13
Go to main E-Print page  Alternative Models of Zebra Patterns in the Event on June 21, 2011  Particle acceleration in coalescent and squashed magnetic islands II. Particle-In-cell approach  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
Evolution of the critical torus instability height and CME likelihood in solar active regions
A Magnetogram-matching Method for Energizing Magnetic Flux Ropes Toward Eruption
A 2D Model for Coronal Bright Points: Association with Spicules, UV bursts, Surges and EUV Coronal Jets
The relativistic solar particle event on 28 October 2021: Evidence of particle acceleration within and escape from the solar corona
Statistical Analysis of Stellar Flares from the First Three Years of TESS Observations
Interface Region Imaging Spectrograph (IRIS) Observations of the Fractal Dimension in the Solar Atmosphere
Clusters of Solar Radio Spikes Modulated by Quasi-Periodic Pulsations in a Confined Flare
Dynamic Property and Magnetic Nonpotentiality of Two Types of Confined Solar Flares
Terrestrial volcanic eruptions and their possible links with solar activity
Transition to turbulence in nonuniform coronal loops driven by torsional Alfvén waves. II. Extended analysis and effect of magnetic twist
Bayesian approach for modeling solar active region global magnetic parameters
Where is the base of the Transition Region? Evidence from TRACE, SDO, IRIS and ALMA observations
The Spectrometer Telescope for Imaging X-rays (STIX) on Solar Orbiter
Detection of spicules termed Rapid Blue-shifted Excursions as seen in the chromosphere via Hα and the transition region via Si iv 1394 line emission
Grid-based imaging in X-rays and gamma-rays with high spatial resolution
It Takes a Village (Invited memoir)
Maximal growth rate of the ascending phase of a sunspot cycle for predicting its amplitude
Starspots Modelling and Flare Analysis on Selected MV Stars
Doubling of minute-long Quasi-Periodic Pulsations from super-flares on a low mass star
Geometric Assumptions in Hydrodynamic Modeling of Coronal and Flaring Loops

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