𝔖 Bobbio Scriptorium
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Hα, hard X-ray, and microwave emissions in the impulsive phase of solar flares

✍ Scribed by Donald F. Neidig

Publisher
Springer
Year
1978
Tongue
English
Weight
734 KB
Volume
57
Category
Article
ISSN
0038-0938

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✦ Synopsis

I have studied the observational relationship between the location of flare sites in active regions and three other observables, viz., Ha line width, hard X-ray burst parameters, and peak microwave fluxes. Results suggest that the strength of the magnetic field plays a role in governing the magnitudes of these emissions. Qualitative relationships are derived on the assumption of proportionality between the spectral maximum frequency of the associated microwave burst and the field strength in the microwave source.

The relationship inferred between the power in thick target electrons (derived from the hard X-ray burst) and the column density of second-level hydrogen atoms (derived from the Ha line widths) is compared with calculations by Brown (1973) andCanfield (1974).

The line widths observed for two white light flares suggest that a criterion for detectable continuum emission in disk flares is an Ha line width ~> 20 ~.

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