E-Print Archive

There are 4021 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
Intermittent turbulent dynamo at very low and high magnetic Prandtl numbers View all abstracts by submitter

Eric Buchlin   Submitted: 2011-11-09 15:48

Context: Direct numerical simulations have shown that the dynamo is efficienteven at low Prandtl numbers, i.e., the critical magnetic Reynolds number Rm_cnecessary for the dynamo to be efficient becomes smaller than the hydrodynamicReynolds number Re when Re -> infinity. Aims: We test the conjecture (Iskakovet al. 2007) that Rm_c actually tends to a finite value when Re -> infinity,and we study the behavior of the dynamo growth factor gamma at very low andhigh magnetic Prandtl numbers. Methods: We use local and nonlocal shell-modelsof magnetohydrodynamic (MHD) turbulence with parameters covering a much widerrange of Reynolds numbers than direct numerical simulations, but ofastrophysical relevance. Results: We confirm that Rm_c tends to a finite valuewhen Re -> infinity. The limit for Rm -> infinity of the dynamo growth factorgamma in the kinematic regime behaves like Re^eta, and, similarly, thelimit for Re -> infinity of gamma behaves like Rmeta', witheta=eta'=0.4. Conclusion: Comparison with a phenomenology based on anintermittent small-scale turbulent dynamo, together with the differencesbetween the growth rates in the different local and nonlocal models, indicate aweak contribution of nonlocal terms to the dynamo effect.

Authors: E. Buchlin
Projects: None

Publication Status: A&A Letters (published)
Last Modified: 2011-11-10 10:58
Go to main E-Print page  Evolution of Hard X-ray Sources and Ultraviolet Solar Flare Ribbons for a Confined Eruption of a Magnetic Flux Rope  Constraining the Kinematics of Coronal Mass Ejections in the Inner Heliosphere with In-Situ Signatures  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
Three-dimensional reconstruction of CME-driven shock-streamer interaction from radio observations: a different take on the diagnostics of coronal magnetic fields
The soft X-ray spectrometer polarimeter SolpeX
Variable emission mechanism of a Type IV radio burst
Inference of magnetic field strength and density from damped transverse coronal waves
Frequency-Distance Structure of Solar Radio Sources Observed by LOFAR
The birth of a coronal mass ejection
Properties of slow magnetoacoustic oscillations of solar coronal loops by multi-instrumental observations
Persistent Quasi-Periodic Pulsations During a Large X-Class Solar Flare
Magnetic helicity and fluxes in an inhomogeneous α squared dynamo
Properties of the Diffuse Emission around Warm Loops in Solar Active Regions
Comparative Study of Microwave Polar Brightening, Coronal Holes, and Solar Wind Over the Solar Poles
3He-rich Solar Energetic Particles from Sunspot Jets
Relative magnetic field line helicity
Forbush decreases and Geomagnetic Storms during a Highly Disturbed Solar and Interplanetary Period, 4‐10 September 2017
Helical Twisting Number and Braiding Linkage Number of Solar Coronal Loops
Small-scale motions in solar filaments as the precursors of eruptions
Modeling of Heliospheric Modulation of Cosmic-Ray Positrons in a Very Quiet Heliosphere
Interpreting magnetic helicity flux in solar flux emergence
Transient Inverse-FIP Plasma Composition Evolution within a Confined Solar Flare
The Role of a Tiny Brightening in a Huge Geo-effective Solar Eruption Leading to the St Patrick's Day Storm

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