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Observational and Theoretical Challenges to Wave or Turbulence Accelerations of the Fast Solar WindWe use both observations and theoretical considerations to show that hydromagnetic waves or turbulence cannot produce the acceleration of the fast solar wind and the related heating of the open solar corona. Waves do exist as shown by Hinode and other observations, and can play a role in the differential heating and acceleration of minor ions but their amplitudes are not sufficient to power the wind, as demonstrated by extrapolation of magnetic spectra from Helios and Ulysses observations. Dissipation mechanisms invoked to circumvent this conclusion cannot be effective for a variety of reasons. In particular, turbulence does not play a strong role in the corona as shown by both eclipse observations of coronal striations and theoretical considerations of line-tying to a nonturbulent photosphere, nonlocality of interactions, and the nature of kinetic dissipation. In the absence of wave heating and acceleration, the chromosphere and transition region become the natural source of open coronal energization. We suggest a variant of the velocity filtration approach in which the emergence and complex churning of the magnetic flux in the chromosphere and transition region continuously and ubiquitously produces the nonthermal distributions required. These particles are then released by magnetic carpet reconnection at a wide range of scales and produce the wind as described in kinetic approaches. Since the carpet reconnection is not the main source of the energization of the plasma, there is no expectation of an observable release of energy in nanoflares.
Document ID
20080047936
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Roberts, D. Aaron
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 24, 2013
Publication Date
December 14, 2008
Subject Category
Astrophysics
Meeting Information
Meeting: American Geophysical Union 2008 Fall Meeting
Location: San Francisco, CA
Country: United States
Start Date: December 14, 2008
End Date: December 20, 2008
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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