Results 21 to 30 of about 53,020 (220)
On the classifications of the solar active regions (ARs); Case study for solar cycles 23 and 24
Egyptian Journal of Remote Sensing and Space Sciences, 2018 The declining phase of solar cycle 23 is an important case of study. Many high energetic solar flares occurred in 2003. The occurrence of high energetic solar X-ray flares (X-type) is related to solar cycle’s phases and the state of the active regions ...
Wael Mohamed +2 more
doaj +1 more source
Solar Flare X‐Ray Impacts on Long Subionospheric VLF Paths
Space Weather, 2021 Solar flares increase the electron number concentration in the daytime ionosphere, potentially affecting radiowave propagation over several frequency ranges.
Samuel R. G. Belcher +6 more
doaj +1 more source
The Astrophysical Journal, 2023 We present light curves and flares from a 7 day, multiwavelength observational campaign of AU Mic, a young and active dM1e star with exoplanets and a debris disk. We report on 73 unique flares between the X-ray to optical data.
Isaiah I. Tristan +15 more
doaj +1 more source
Evolution of Elemental Abundances during B-Class Solar Flares: Soft X-Ray Spectral Measurements with Chandrayaan-2 XSM [PDF]
Astrophysical Journal, 2021 The Solar X-ray Monitor (XSM) payload on board Chandrayaan-2 provides disk-integrated solar spectra in the 1–15 keV energy range with an energy resolution of 180 eV (at 5.9 keV) and a cadence of 1 s.
B. Mondal +8 more
semanticscholar +1 more source
September 2017 Solar Flares Effect on the Middle Atmosphere
Remote Sensing, 2022 This paper examines the response of the upper atmosphere to increased radiation following exceptional solar activity in September 2017. The active region of the Sun AR2673 has caused intense solar-terrestrial disturbance. This active region has generated
Polina Pikulina +3 more
doaj +1 more source
The Astrophysical Journal, 2023 Three generations of the Miniature X-ray Solar Spectrometer (MinXSS) have flown on small satellites with the goal “to explore the energy distribution of soft X-ray (SXR) emissions from the quiescent Sun, active regions, and during solar flares, and to ...
Thomas N. Woods +13 more
doaj +1 more source
The spectral evolution of impulsive solar X-ray flares. II. Comparison of observations with models [PDF]
, 2005 We study the evolution of the spectral index and the normalization (flux) of the non-thermal component of the electron spectra observed by RHESSI during 24 solar hard X-ray flares.
P. Grigis, A. O. Benz
semanticscholar +1 more source
Soft X-ray solar flare cycles [PDF]
Proceedings of the International Astronomical Union, 2004 We present a statistical investigation of soft X-ray (SXR) solar flare occurrence over the last three 11-yr solar cycles (SCs 21-23, corresponding to the period 1976-2003). We studied not only the monthly number of flares, but we also used an index that estimate the energy emitted by flares in the SXR 1-8 ˚ and (Qx) that we find it better defines their
Georgeta Maris +2 more
openaire +1 more source
Influence of solar X-ray flares on the earth-ionosphere waveguide
, 2005 SUMMARY: A simultaneous analysis of solar are X-ray irradiance and VLF signal amplitude on the GQD/22.1 kHz trace was carried out. Solar are data were taken from GOES 12 satellite listings.
D. Grubor, Desanka Šulić, V. Žigman
semanticscholar +1 more source
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
doaj +1 more source