E-Print Archive

There are 3897 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
Quasi-periodic pulsations in solar and stellar flares: re-evaluating their nature in the context of power-law flare Fourier spectra View all abstracts by submitter

Andrew Inglis   Submitted: 2014-10-31 08:31

The nature of quasi-periodic pulsations in solar and stellar flares remains debated. Recent work has shown that power-law-like Fourier power spectra, also referred to as 'red' noise processes, are an intrinsic property of solar and stellar flare signals, a property that many previous studies of this phenomenon have not accounted for. Hence a re-evaluation of the existing interpretations and assumptions regarding QPP is needed. Here we adopt a Bayesian method for investigating this phenomenon, fully considering the Fourier power law properties of flare signals. Using data from the PROBA2/LYRA, Fermi/GBM, Nobeyama Radioheliograph and Yohkoh/HXT instruments, we study a selection of flares from the literature identified as QPP events. Additionally we examine optical data from a recent stellar flare that appears to exhibit oscillatory properties. We find that, for all but one event tested, an explicit oscillation is not required in order to explain the observations. Instead, the flare signals are adequately described as a manifestation of a power law in the Fourier power spectrum, rather than a direct signature of oscillating components or structures. However, for the flare of 1998 May 8, strong evidence for the existence of an explicit oscillation with P ~ 14-16 s is found in the 17 GHz radio data and the 13-23 keV Yohkoh HXT data. We conclude that, most likely, many previously analysed events in the literature may be similarly described in terms of power laws in the flare Fourier power spectrum, without the need to invoke a narrowband, oscillatory component. As a result the prevalence of oscillatory signatures in solar and stellar flares may be less than previously believed. The physical mechanism behind the appearance of the observed power laws is discussed.

Authors: A. R. Inglis, J. Ireland, M. Dominique
Projects: None

Publication Status: ApJ, accepted
Last Modified: 2014-10-31 09:40
Go to main E-Print page  Nonlinear slow magnetoacoustic waves in coronal plasma structures  Can we explain non-typical solar flares?  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
Computation of Relative Magnetic Helicity in Spherical Coordinates
Some characteristics of the GLE on 10 September 2017
Quasi-periodic Pulsations in a Solar Microflare
Homologous large-amplitude Nonlinear fast-mode Magnetosonic Waves Driven by Recurrent Coronal Jets
EUV Waves Driven by Sudden Expansion of Transequatorial Loops Caused by Solar Coronal Jets
Dispersively formed quasi-periodic fast magnetosonic wavefronts due to the eruption of a nearby mini-filament
Mini-filament Eruptions Triggering Confined Solar Flares Observed by ONSET and SDO
LOFAR observations of fine spectral structure dynamics in type IIIb radio bursts
Critical magnetic field strengths for solar coronal plumes in quiet regions and coronal holes?
Does Nearby Open Flux Affect the Eruptivity of Solar Active Regions?
Cyclic Changes of the Sun's Seismic Radius
Onset of Photospheric Impacts and Helioseismic Waves in X9.3 Solar Flare of September 6, 2017
Solar Cycle Variations of Rotation and Asphericity in the Near-Surface Shear Layer
Solar coronal loop dynamics near the null point above active region NOAA 2666
Energetics of small electron acceleration episodes in the solar corona from radio noise storm observations
The origin of the modulation of the radio emission from the solar corona by a fast magnetoacoustic wave
Indirect solar wind measurements using archival cometary tail observations
Helium abundance and speed difference between helium ions and protons in the solar wind from coronal holes, active regions, and quiet Sun
Always a Farm Boy
Effect of transport coefficients on excitation of flare-induced standing slow-mode waves in coronal 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



© 2003 Solar Physics Group - Montana State University