Results 161 to 170 of about 27,428 (205)

Solar flare hard X-ray observations

Solar Physics, 1988
Recent hard X-ray observations of solar flares are reviewed with emphasis on results obtained with instruments on the Solar Maximum Mission satellite. Flares with three different sets of characteristics, designated as Type A, Type B, and Type C, are discussed and hard X-ray temporal, spatial, spectral, and polarization measurements are reviewed in this
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Prospects for solar flare X-ray polarimetry

Solar Physics, 1988
The history of solar flare X-ray polarimetry is reviewed and it is shown that as yet, there is no experimental evidence for such polarization. The present experimental limits are at the level of a few percent but these results may be biased by a large thermal component at low energies which may decrease the apparent polarization.
Gary Chanan, A. Gordon Emslie, Robert Novick   +2 more
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X-ray precursors in solar flares

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science, 2000
Abstract A clear understanding of the physics of flares remains an important goal of solar research. One important aspect of this question is to determine the various stages or phases of flares. Two stages of flares have long been known: a gradual, or thermal phase, best observed in soft X-rays, and an impulsive phase, best observed in hard X-rays ...
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High-Energy X Rays During Solar Flares

Physical Review Letters, 1961
X-radiation was measured coincidently with other cosmic radiation from solar flares observed on Oct. 12, 1960. Measurements were taken from a baloon that reached a peak altitude of 1.2 x 10/sup 5/ ft. Two events were recorded on the x-ray scintillation counter, one at 1730 UT and the other at 1747 UT.
J. I. Vette, F. G. Casal
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Hard X-ray Emission Processes in Solar Flares

Solar Physics, 1987
Solar hard X-ray emission is one of the most direct diagnostics of accelerated particles during solar flares. In this review, the current understanding of hard X-ray emission processes is discussed: first the different emission mechanisms (in particular inverse Compton radiation, energetic ion or electron bremsstrahlung) are presented and the ...
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Hard X-ray solar flare polarimetry with RHESSI

Advances in Space Research, 2004
Abstract Although designed primarily as a hard X-ray imager and spectrometer, the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) is also capable of measuring the polarization of hard X-rays (20–100 keV) from solar flares. This capability arises from the inclusion of a small unobstructed Be scattering element that is strategically located ...
McConnell, Mark L, Smith, D M, Emslie, A G, Hurford, G J, Lin, R P, Ryan, James M.   +5 more
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X-Ray Observations of Solar Flares

1988
Major observational highlights of the last solar maximum are reviewed with emphasis on the results obtained by Japanese Hinotori satellite. Three different types of flares were observed by Hinotori: Type A flares have purely thermal nature, and generate dense superhot plasma throughout the flare evolution.
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Coronal X-ray activity preceding solar flares

Solar Physics, 1985
The characteristics of coronal emplacements preceding solar flares were investigated based on a comprehensive survey of Skylab soft X-ray images. A search interval of 30 min before flare was used in the X-ray observations. X-ray images with preflare enhancements were compared with high resolution H-alpha images and photospheric magnetograms and ...
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SOLAR FLARE DYNAMICS OBTAINED BY X-RAY OBSERVATIONS

Astronomical & Astrophysical Transactions, 2003
The dynamic properties of solar flares are considered on the basis of the spectral observations of soft X-rays of more than 180 flares obtained during the last two decades. The random non-thermal velocities are in the range from 60 to 580 km s-1 but mainly change from 110 to 190 km s−1.
G. Porfir'Eva, G. Yakunina
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Impulsive X-ray brightenings in solar flares

Advances in Space Research, 1996
Abstract An analysis of 40 solar flares observed with the Yohkoh satellite was carried out to investigate the temporal relationship between rapid hard and soft X-ray flaring. Using Bragg Crystal Spectrometer (BCS) and Hard X-ray Telescope (HXT) data it was found that in every event the Neupert effect occurred throughout most of the impulsive phase.
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