Results 171 to 180 of about 10,736 (185)

Unusually low coronal radio emission at the solar minimum

Solar Physics, 1992
We present two-dimensional observations of the quiet Sun at 73.8, 50.0, and 38.5 MHz obtained with the Clark Lake Radioheliograph during the sunspot minimum period of September 1986. The observed peak brightness temperatures during the entire period of sunspot minimum are found to be extremely low, lying in the range (0.6 × 105 K − 2.5 × 105 K).
G. Thejappa, M. R. Kundu
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Oscillations of coronal loops and second pulsations of solar radio emission

Astronomy Letters, 2007
The dispersion properties of the sausage eigenmodes of oscillations in a thin magnetic flux tube are numerically analyzed in terms of ideal magnetohydrodynamics (MHD). The period of the modes accompanied by the emission of MHD waves into the surrounding medium, which leads to acoustic damping of oscillations, is determined by the radius of the tube ...
Yu. G. Kopylova, A. V. Melnikov, A. V. Stepanov, Yu. T. Tsap, T. B. Goldvarg   +4 more
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Density Depletion in a Coronal Flux Tube Associated With Solar Radio Emission

Solar Physics, 2006
A discussion, which is motivated by recent study of solar radio emission, is presented to address the issue under what conditions the depletion of plasma density in a flux tube in the corona may take place. Two particular situations are of interest: One is that density is depleted due to the presence of beams of energetic particles, and the other is ...
C. S. Wu, C. B. Wang, Q. M. Lu
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Solar Radio Emission as a Prediction Technique for Coronal Mass Ejections’ Detection

Proceedings of the International Astronomical Union, 2017
AbstractIn this report we present a possible scheme of short-term CME detection forecasting developed on the basis of statistical analysis of solar radio emission regularities prior to “isolated” solar Coronal Mass Ejections registered in 1998, 2003, 2009-2013.
Vladimir M. Fridman, Olga A. Sheiner
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Bursts of kinetic Alfvén waves and coronal radio emission at 2–3 solar radii

2015 1st URSI Atlantic Radio Science Conference (URSI AT-RASC), 2015
Solar radio observations at 10–30 MHz have been carried out recently using radio telescopes UTR-2 (world's largest radio telescope at decametric wavelengths near Kharkov, Ukraine) and URAN-2 (Poltava, Ukraine). High sensitivity and time resolution of these observations allowed revealing many new interesting features of the coronal radio emission (V. N.
Yuriy Voitenko, Valentin Melnik, Viviane Pierrard   +2 more
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Physical characteristics of the radio emission of solar coronal holes

Geomagnetism and Aeronomy, 2016
This paper presents a brief overview of works dedicated to the studies of solar coronal holes (CH). Special attention is paid to CH studies at millimeter and centimeter wavelengths. The observational data in the millimeter range, combined with satellite observations in the ultraviolet and soft X-ray range, as well as solar eclipse observations of March
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A study of solar radio emission in the light of Sengupta's model of coronal active regions

Solar Physics, 1973
Daily solar radio flux at six different frequencies in dm, cm and mm wavelength regions has been studied for 182 days from December 1, 1970 to May 30, 1971. It is found that the slowly varying component of the centimeter wave emission correlates well with the physical model of the coronal active regions derived by Sengupta (Sengupta, 1971b) from which,
P. R. Sengupta, A. K. Chakraborty
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Specific features of radio emissions of coronal holes based on eclipse and noneclipse observations at a solar activity minimum

Geomagnetism and Aeronomy, 2012
Solar coronal holes (CHs) at a minimum of the 23rd activity cycle were investigated using Solar and Heliospheric Observatory (SOHO) data, ground-based observational data from the radio telescopes of the Kislovodsk Solar Station, Pulkovo Observatory (KSS PO), Russian Academy of Sciences, and radioheliograph data from the Nobeyama Observatory (Japan ...
A. D. Shramko, S. A. Guseva
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Periodicities in the Time Series of Solar Coronal Radio Emissions and Chromospheric uv Emission Lines

Solar Physics, 2002
A spectral analysis of the time series of daily values of ten solar coronal radio emissions in the range 275–1755 MHz, the 2800 MHz radio flux, several UV emission lines in the chromosphere and in the transition region, and sunspot number, for six successive intervals of 132 days each, during June 1997–July 1999 (26 months) showed that the spectral ...
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Solar radio emission and diagnostics of Solar coronal plasma

2008
Sunčeva atmosfera, protkana izranjajućim magnetskim poljima, dinamičan je plazmeni sustav u kojem dolazi od brojnih eruptivnih procesa. Najveće provale energije su Sunčevi bljeskovi i koronini izbačaji tijekom kojih se magnetska energija pretvara u toplinsku, dolazi do ubrzavanja snopova visokoenergetskih čestica, i stvaranja udarnih valova. Intenzitet
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