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Start Over Subject solar flares

12. The influence of HXIS on our appreciation of solar flares

Creator:
Simnett, G. M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
heliophysics and solar flares
Language:
Czech
Description:
The resuits of the Hard X-Ray Imaging Spectrometer on the Solar Maximum Mission are reviewed. Particular emphasis ís given to those results which address phenomena which cannot easily be studied by the other instruments. Among the important discoveries are the following: it has been established that during the onset of the impulsive phase the hard X-rays are emitted from the footpoints of the flare loop, cospatial with the Hα kernels; very large, coronal loops, often containing plasma with temperatures up to 10^K, are probably quasi-permanent features of the solar atmosphere; there are often soft X-ray precursors from points separated by ^ 10^ km which signal the onset of coronal mass ejections; following the onset of the impulsive phase hot plasma is observed to rise into the corona, sometimes inhibiting further energy input to the chromosphere; surges and prominences may be emitting weakly in soft X-rays during certain phases of their evolution; rapidly-varying (^ 10‘s) soft X-ray spikes are occasionally seen, with unpredictable corresponding hard X-rays; and there has been a tentative identification of photospheric albedo, backscattered from the hard X-ray emitting plasma as it rises into the low corona.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

13. The observations of solar flares in the Hα and Hel γ 10830 line

Creator:
Baranovsky, E. A., Ogir, M. B., Stepanian, N. N., and Shumko, A. V.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
observations and solar flares
Language:
Czech
Description:
Simultaneous photographic observations in Hα, and photoelectric observations in Hel γ 10830 line are analyzed for two flares of importance sf and 1B. For the estimation of physical conditions in the chromosphere of flares the non-LTE calculations of the Hα and γ 10830 line profiles were made for a number of model atmospheres. Comparing the observed values of Hα and γ 10830 line intensities vvith calculated ones, we derived the temperature changes during the development of active formations for two levels of chromosphere (Ihe levels of Hα and γ 10830 line formation).
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public