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Record Details

Record 42 of 46360
Hard X-ray bremsstrahlung production in solar flares by high-energy proton beams
External Online Source: doi:10.1086/163408
Author and Affiliation:
Emslie, A. G.(Alabama, University, Huntsville, United States)
Brown, J. C.(California, University, San Diego, United States)
Abstract: The possibility that solar hard X-ray bremsstrahlung is produced by acceleration of stationary electrons by fast-moving protons, rather than vice versa, as commonly assumed, was investigated. It was found that a beam of protons which involves 1836 times fewer particles, each having an energy 1836 times greater than that of the electrons in the equivalent electron beam model, has exactly the same bremsstrahlung yield for a given target, i.e., the mechanism has an energetic efficiency equal to that of conventional bremsstrahlung models. Allowance for the different degrees of target ionization appropriate to the two models (for conventional flare geometries) makes the proton beam model more efficient than the electron beam model, by a factor of order three. The model places less stringent constraints than a conventional electron beam model on the flare energy release mechanism. It is also consistent with observed X-ray burst spectra, intensities, and directivities. The altitude distribution of hard X-rays predicted by the model agrees with observations only if nonvertical injection of the protons is assumed. The model is inconsistent with gamma-ray data in terms of conventional modeling.
Publication Date: Aug 15, 1985
Document ID:
19850064307
(Acquired Nov 28, 1995)
Accession Number: 85A46458
Subject Category: SOLAR PHYSICS
Document Type: Journal Article
Publication Information: Astrophysical Journal, Part 1; p. 648-653; (ISSN 0004-637X); 295
Publisher Information: United States
Contract/Grant/Task Num: NSF ATM-82-17025; NSF ATM-83-03172; NAGW-294
Financial Sponsor: NASA; United States
Organization Source: Alabama Univ.; Huntsville, AL, United States
California Univ.; San Diego, CA, United States
Description: 6p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: BREMSSTRAHLUNG; ELECTRON BEAMS; GAMMA RAY BURSTS; PROTON BEAMS; SOLAR FLARES; SOLAR X-RAYS; INTEGRAL EQUATIONS; PLASMA DENSITY
Imprint And Other Notes: Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 295, Aug. 15, 1985, p. 648-653. SERC-supported research.
Miscellaneous Notes: SERC-supported research
Availability Source: Other Sources
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