Results 21 to 30 of about 27,428 (205)
Solar abundances from X-ray flare observations [PDF]
Monthly Notices of the Royal Astronomical Society, 1981 X-ray line and continuum observations are used to derive the absolute coronal abundances of Si, S, Ar, and Ca from lines of hydrogenor helium-like ions. For Si (7.7+0.2, -0.3) and Ca (6.5+0.1, -0.3) the measured coronal values are in good agreement with the photospheric values, but the value for S (6.9+0.1, -0.3) is approximately half of the ...
N. J. Veck, J. H. Parkinson
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Inverse Compton X-rays from relativistic flare electrons and positrons [PDF]
, 2009 <p><b>Context:</b> In solar flares, inverse Compton scattering (ICS) of photospheric photons might give rise to detectable hard X-ray photon fluxes from the corona where ambient densities are too low for significant bremsstrahlung or ...
A. L. MacKinnon +37 more
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Evolutionary Relationship between Sunspot Groups and Soft X-Ray Flares over Solar Cycles 21–25
The Astrophysical Journal, 2023 Studying the interaction between solar flares and sunspot groups (SGs) is crucial for understanding and predicting solar activity. We examined the distribution, correlation, and flaring rates in the northern and southern hemispheres to reveal the ...
Jiaqi Lin +5 more
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Applied Sciences, 2021 Strong radiation from solar X-ray flares can produce increased ionization in the terrestrial D-region and change its structure. Moreover, extreme solar radiation in X-spectral range can create sudden ionospheric disturbances and can consequently affect ...
Vladimir A. Srećković +4 more
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Was an Outburst of Aquila X-1 a Magnetic Flare?
, 2010 I point to an interesting similarity in the radio and the soft X-ray light curves between the November 2009 outburst of the X-ray binary Aquila X-1 and some solar flares.
Benz +19 more
core +1 more source
Cold Solar Flares. I. Microwave Domain
The Astrophysical Journal, 2023 We identify a set of ∼100 “cold” solar flares and perform a statistical analysis of them in the microwave range. Cold flares are characterized by a weak thermal response relative to nonthermal emission.
Alexandra L. Lysenko +6 more
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Probability Distribution Functions of Solar and Stellar Flares
Physics, 2022 The paper studies the soft X-ray data of solar flares and found that the distribution functions of flare fluence are successfully modeled by tapered power law or gamma function distributions whose power exponent is slightly smaller than 2, indicating ...
Takashi Sakurai
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X-Ray Polarization of Solar Flares Measured with Rhessi [PDF]
Solar Physics, 2006 The degree of linear polarization in solar flares has not yet been precisely determined despite multiple attempts to measure it with different missions. The high energy range in particular has very rarely been explored, due to its greater instrumental difficulties.
Suarez-Garcia, E. +6 more
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Role of hard X-ray emission in ionospheric D-layer disturbances during solar flares
Earth, Planets and Space, 2022 Any disturbance of the ionosphere may affect operational activities based on HF communication. The electron density is a critical parameter that controls levels of HF-signal absorption.
Carine Briand +3 more
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Wavelet Analysis of Solar Flare Hard X‐Rays
The Astrophysical Journal, 1998 We apply a multiresolution analysis to hard X-ray (HXR) time profiles f(t) of solar flares. This method is based on a wavelet transform (with triangle-shaped wavelets), which yields a dynamic decomposition of the power at different timescales T, the scalogram P(T, t).
Kliem, Bernhard (Dr.) +5 more
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