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Record 34 of 2806
Solar flare hard and soft x ray relationship determined from SMM HXRBS and BCS data
Author and Affiliation:
Toot, G. David(Alfred Univ., NY, United States)
Abstract: The exact nature of the solar flare process is still somewhat a mystery. A key element to understanding flares if the relationship between the hard x rays emitted by the most energetic portions of the flare and the soft x rays from other areas and times. This relationship was studied by comparing hard x ray light curved from the Hard X-Ray Burst Spectrometer (HXRBS) with the soft x ray light curve and its derivation from the Bent Crystal Spectrometer (BCS) which is part of the X-Ray Polychrometer (XRP), these instruments being on the Solar Maximum Mission spacecraft (SMM). Data sample was taken from flares observed with the above instruments during 1980, the peak of the previous maximum of solar activity. Flares were chosen based on complete coverage of the event by several instruments. The HXRBS data covers the x ray spectrum from about 25 keV to about 440 keV in 15 spectral channels, while the BCS data used covers a region of the Spectrum around 3 angstroms including emission from the Ca XIX ion. Both sets of data were summed over their spectral ranges and plotted against time at a maximum time resolution of around 3 seconds. The most popular theory of flares holds that a beam of electrons produces the hard x rays by bremsstrahlung while the soft x rays are the thermal response to this energy deposition. The question is whether the rate of change of soft x ray emission might reflect the variability of the electron beam and hence the variability of the hard x rays. To address this, we took the time derivative of the soft x ray light curve and compared it to the hard flares, 12 of them showed very closed agreement between the soft x ray derivative and the hard x ray light curve. The other five did not show this behavior but were similar to each other in general soft x ray behavior. Efforts to determine basic differences between the two kinds of flares continue. In addition the behavior of soft x ray temperature of flares was examined.
Publication Date: Sep 01, 1989
Document ID:
(Acquired Nov 07, 1995)
Accession Number: 91N25940
Subject Category: SOLAR PHYSICS
Coverage: Abstract Only
Document Type: Conference Paper
Publication Information: Maryland Univ., The 1989 NASA-ASEE Summer Faculty Fellowship Program in Aeronautics and Research; p 38
Publisher Information: United States
Financial Sponsor: NASA; United States
Organization Source: Alfred Univ.; Dept. of Physics.; NY, United States
Description: 1p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: No Copyright
Imprint And Other Notes: In Maryland Univ., The 1989 NASA-ASEE Summer Faculty Fellowship Program in Aeronautics and Research p 38 (SEE N91-25914 17-82)
Availability Source: Other Sources
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