Results 181 to 190 of about 18,154 (212)

Interpretation of X-ray spectra from solar flares

Advances in Space Research, 1991
Abstract A technique developed for analysing the SMM X-ray spectra has been adapted to the interpretation of high resolution cooled germanium flare spectra. It is shown that these can be fitted equally well by simple all thermal or non-thermal distributions, and that the data set is insufficient to determine the non-thermal nature of the flare.
A.H. Gabriel, F. Bely-Dubau, F. Millier
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Microwave solar flare spectra of complex magnetic ambient

AIP Conference Proceedings, 2005
The magnetic field lines were never so depicted as in the recent results about active regions on the sun from the EUV experiments on board of SOHO and TRACE satellites. The main result is a clear complexity of the, as called, magnetic arcs on top of the sunspots with arc second spatial resolution of the field lines connecting different magnetic ...
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Microwave burst spectra and solar flare magnetic fields

Solar Physics, 1977
Microwave burst spectra are compared with the position, within the active region, of their associated flares observed in Hα. The magnetic fields predicted by Takakura's burst model (1972) are found to be in reasonable agreement with the fields expected at the flare locations.
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Atomic physics calculations relevant to solar flare spectra

Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences, 1991
Solar flare spectra in the ultraviolet and X-ray wavelength regions are rich in emission lines from highly ionized ions, formed at temperatures around 10 7 K. These lines can be used as valuable diagnostics for probing the physical conditions in solar flares. Such analyses require accurate atomic data for excitation,
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Solar soft X-ray flare spectra from OSO-4

Solar Physics, 1970
Solar flare spectral data, covering the wavelength range 0.7–8.5 A, are derived from the NRL Bragg crystal spectrometers aboard OSO-4. A detailed analysis of the soft X-ray spectra for the 3b flare of 16 November 1967 (2140 UT) is presented, and it is found that electron temperatures derived from continua and emission lines are compatible with a two or
J. F. Meekins, G. A. Doschek, H. Friedman, T. A. Chubb, R. W. Kreplin   +4 more
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High-resolution X-ray spectra of solar flares

Advances in Space Research, 2006
Abstract I discuss high-resolution solar flare soft X-ray spectra and also comment on some recent results from extreme ultraviolet (EUV) spectroscopy. Spectra of solar flares at these wavelengths have been recorded since the late 1960s, beginning primarily with the NASA Orbiting Solar Observatory (OSO) series of spacecraft.
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Determining the Spatial Variation of Accelerated Electron Spectra in Solar Flares

AIP Conference Proceedings, 2008
The RHESSI spacecraft images hard X‐ray emission from solar flares with an angular resolution down to ∼2″ and an energy resolution of 1 keV. For such a Rotating Modulation Collimator (RMC) instrument, imaging information is gathered not as a set of spatial images, but rather as a set of (energy‐dependent) spatial Fourier components (termed visibilities)
A. Gordon Emslie, G. J. Hurford, Eduard P. Kontar, Anna Maria Massone, Michele Piana, Marco Prato, Yan Xu, Gang Li, Qiang Hu, Olga Verkhoglyadova, Gary P. Zank, R. P. Lin, J. Luhmann   +12 more
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Solar Flare X-ray Spectra from the P78-1 Spacecraft

Solar Physics, 1983
Results from the high resolution solar X-ray spectrometer experiments on the P78-1 spacecraft are discussed. These results concern physical quantities such as electron temperature and density, turbulence, mass motions, and state of ionization equilibrium, characteristic of the thermal soft X-ray emitting flare plasma, and the time behavior of these ...
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On helium-like 1s2l?1snl? transitions in solar flare spectra

Solar Physics, 1974
Expected wavelengths and intensities are computed for 1s2l−1snl′ transitions in helium-like ions of the abundant elements from oxygen to iron, under coronal conditions. Probable observations of some of these lines, in the spectra of solar flares, are discussed and attention is called to a possible reversal of singlet and triplet intensities as compared
S. O. Kastner, W. M. Neupert, M. Swartz
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Recombination edges observed in solar soft X-ray flare spectra

Solar Physics, 1970
Edges in the solar soft X-ray flare continuum have been observed with the NRL Bragg crystal spectrometer aboard OSO-4. The edges near 2.06 A, 2.8 A, and 4.46 A are interpreted to be due to an innershell dielectronic recombination process, details of which are presented.
J. F. Meekins, G. A. Doschek
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