E-Print Archive

There are 4594 abstracts currently viewable.


Advanced Search
Main Page Add New E-Print Submitter
News Help/FAQ About Preferences
Manage Key Phrase
The spectral evolution of impulsive solar X-ray flares. II.Comparison of observations with models View all abstracts by submitter

Paolo Grigis   Submitted: 2005-01-20 08:10

We study the evolution of the spectral index and the normalization (flux) of the non-thermal component of the electron spectra observed by RHESSI during 24 solar hard X-ray flares. The quantitative evolution is confronted with the predictions of simple electron acceleration models featuring the soft-hard-soft behaviour. The comparison is general in scope and can be applied to different acceleration models, provided that they make predictions for the behavior of the spectral index as a function of the normalization. A simple stochastic acceleration model yields plausible best-fit model parameters for about 77% of the 141 events consisting of rise and decay phases of individual hard X-ray peaks. However, it implies unphysically high electron acceleration rates and total energies for the others. Other simple acceleration models such as constant rate of accelerated electrons or constant input power have a similar failure rate. The peaks inconsistent with the simple acceleration models have smaller variations in the spectral index. The cases compatible with a simple stochastic model require typically a few times 1036 electrons accelerated per second at a threshold energy of 18 keV in the rise phases and 24 keV in the decay phases of the flare peaks.

Authors: Grigis, P. C. and Benz, A. O.
Projects: RHESSI

Publication Status: accepted by A&A
Last Modified: 2005-01-20 08:10
Go to main E-Print page  Regularized Energy-Dependent Solar Flare Hard X-Ray Spectral Index  Astrophysics in 2004 - Section 2: The Sun  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
Repeated Type III Burst Groups Associated with a B-Class Flare and a Narrow-Width CME
Separating the effects of earthside and far side solar events. A case study.
Deciphering The Slow-rise Precursor of a Major Coronal Mass Ejection
Three-dimensional Turbulent Reconnection within Solar Flare Current Sheet
Sequential Remote Brightenings and Co-spatial Fast Downflows during Two Successive Flares
A Model for Confined Solar Eruptions Including External Reconnection
The eruption of a magnetic flux rope observed by Solar Orbiter and Parker Solar Probe
Comprehensive radiative MHD simulations of eruptive flares above collisional polarity inversion lines
An Anisotropic Density Turbulence Model from the Sun to 1 au Derived From Radio Observations
Comparison of damping models for kink oscillations of coronal loops
On the three-dimensional relation between the coronal dimming, erupting filament and CME. Case study of the 28 October 2021 X1.0 event
Polarisation of decayless kink oscillations of solar coronal loops
CME Propagation Through the Heliosphere: Status and Future of Observations and Model Development
30-min Decayless Kink Oscillations in a Very Long Bundle of Solar Coronal Plasma Loops
The Role of High-Frequency Transverse Oscillations in Coronal Heating
ARTop: an open-source tool for measuring Active Region Topology at the solar photosphere
Spectral Observations and Modeling of a Solar White-light Flare Observed by CHASE
New cases of super-flares on slowly rotating solar-type stars and large amplitude super-flares in G- and M-type main-sequence stars
Constraints on the variable nature of the slow solar wind with the Wide-Field Imager on board the Parker Solar Probe
Prediction of short stellar activity cycles using derived and established empirical relations between activity and rotation periods

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