NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Electron pitch angle scattering and the impulsive phase microwave and hard X-ray emission from solar flaresObservations and theoretical considerations have led to a model for impulsive phase flare emission involving the heating and acceleration of thermal electrons in the coronal part of a magnetic loop. The bulk of the heated gas is confined between conduction fronts, but particles with velocities a few times greater than the thermal velocity can escape into the lower part of the loop. It is shown that, when the electron gyrofrequency exceeds the plasma frequency, the escaping electrons are unstable to the generation of electrostatic plasma waves which scatter the particles in pitch angle to a nearly isotropic distribution. It is also shown that this scattering can (1) enhance the microwave emission from the upper part of the loop, and (2) due to the Landau damping of both low and high phase velocity waves, can lead to one or two breaks in the impulsive-phase hard X-ray spectrum.
Document ID
19820050804
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Holman, G. D.
(Maryland Univ. College Park, MD, United States)
Kundu, M. R.
(Maryland Univ. College Park, MD, United States)
Papadopoulos, K.
(Maryland, University College Park, MD, United States)
Date Acquired
August 10, 2013
Publication Date
June 1, 1982
Publication Information
Publication: Astrophysical Journal
Subject Category
Solar Physics
Accession Number
82A34339
Funding Number(s)
CONTRACT_GRANT: NAGW-81
CONTRACT_GRANT: NSF ATM-81-03089
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available