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Extreme Ultraviolet Emission Lines of ca xv in Solar and Laboratory Spectra
Solar Physics, 2003New R-matrix calculations of electron impact excitation rates in Ca xv are used to derive theoretical electron density diagnostic emission line intensity ratios involving 2s22p2–2s2p3 transitions, specifically R1=I(208.70 A)/I(200.98 A), R2=I(181.91 A)/I(200.98 A), and R3=I(215.38 A)/I(200.98 A), for a range of electron temperatures (Te=106.4–106.8 K ...
Keenan, Francis +3 more
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Direct measurements of the gradual extreme ultraviolet emission from large solar flares
Solar Physics, 1983Broadband sensors aboard the Naval Research Laboratory's SOLRAD 11 satellites measured solar emission in the 0.5 to 3 A, 1 to 8 A, 8 to 20 A, 100 to 500 A, 500 to 800 A, and 700 to 1030 A bands. Data from sixteen large flares show that the EUV emission is dominated by gradual emission which parallels the soft X-ray emission in duration and magnitude ...
D. M. Horan, R. W. Kreplin, K. P. Dere
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Solar extreme ultraviolet emissions in the range 260?1300 � observed from OSO-III
Solar Physics, 1969Solar electromagnetic radiation of wavelengths ranging from 260–1300 A was measured by a grazing-incidence grating spectrometer on OSO-III, which operated as a monochromator with a wavelength bandwidth of about 2 A and an acceptance angle covering the whole disk without any instrumental discrimination of source locations.
H. E. Hinteregger, L. A. Hall
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Solar Physics, 1973
The time structure and intensity of OSO-6 observations of EUV bursts were studied in relation to the corresponding 10-1030 A enhancements deduced from SFD data. Impulsive EUV emissions from lines normally emitted from either the chromosphere or from the chromosphere-corona transition region rise simultaneously with the 10-1030 A flash, to within the ...
R. F. Donnelly, A. T. Wood, R. W. Noyes
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The time structure and intensity of OSO-6 observations of EUV bursts were studied in relation to the corresponding 10-1030 A enhancements deduced from SFD data. Impulsive EUV emissions from lines normally emitted from either the chromosphere or from the chromosphere-corona transition region rise simultaneously with the 10-1030 A flash, to within the ...
R. F. Donnelly, A. T. Wood, R. W. Noyes
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Publications of the Astronomical Society of Japan, 1963
Abstract Models of the solar transition layer between the chromosphere and the corona are constructed to give a reasonable explanation for the rocket- and eclipse observations and also for radio emission. Models for the undisturbed sun, both at the sunspot maximum and Jllinimum, and for the active region are proposed in the present ...
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Abstract Models of the solar transition layer between the chromosphere and the corona are constructed to give a reasonable explanation for the rocket- and eclipse observations and also for radio emission. Models for the undisturbed sun, both at the sunspot maximum and Jllinimum, and for the active region are proposed in the present ...
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Solar Physics, 1984
The intensity ratios of Niii, Oiii, Oiv, and Ov lines observed by the HCO experiment on Skylab are compared with the results of recent multilevel calculations. It is found that solar transition-region spectra require Lyman continuum absorption. The equivalent optical thickness of the absorbers causing the weakening is found to be 1.6–1.7 for a quiet ...
Mitsuo Kanno +2 more
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The intensity ratios of Niii, Oiii, Oiv, and Ov lines observed by the HCO experiment on Skylab are compared with the results of recent multilevel calculations. It is found that solar transition-region spectra require Lyman continuum absorption. The equivalent optical thickness of the absorbers causing the weakening is found to be 1.6–1.7 for a quiet ...
Mitsuo Kanno +2 more
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Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1971
Abstract A number of time profiles are presented which show how the flux of radiation in the wavelength bands 0.1 to 0.3 nm, 0.3 to 0.9 nm, 0.8 to 1.6 nm and at 30.4 nm change during flares. The first sign of a flare is often a decrease of flux at 30.4 nm followed by an increase in the X-ray emission. In general, the higher the photon
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Abstract A number of time profiles are presented which show how the flux of radiation in the wavelength bands 0.1 to 0.3 nm, 0.3 to 0.9 nm, 0.8 to 1.6 nm and at 30.4 nm change during flares. The first sign of a flare is often a decrease of flux at 30.4 nm followed by an increase in the X-ray emission. In general, the higher the photon
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Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1971
Abstract The purpose of this review is to consider the analysis of extreme u.v. space observations for the interpretation of the Quiet Sun (Q.), active regions (a.r.) and flares (fl.). The three components must be segregated from one another using the observational data that exists.
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Abstract The purpose of this review is to consider the analysis of extreme u.v. space observations for the interpretation of the Quiet Sun (Q.), active regions (a.r.) and flares (fl.). The three components must be segregated from one another using the observational data that exists.
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Solar Extreme and Far Ultraviolet Radiation Modeling for Aeronomic Calculations
Remote Sensing, 2021A A Nusinov
exaly