Results 31 to 40 of about 152,015 (264)
Sun-as-a-Star Observation of Flares in Lyman {\alpha} by the PROBA2/LYRA radiometer [PDF]
, 2012 There are very few reports of flare signatures in the solar irradiance at H i Lyman {\alpha} at 121.5 nm, i.e. the strongest line of the solar spectrum. The LYRA radiometer onboard PROBA2 has observed several flares for which unambiguous signatures have ...
Dammasch, I. E. +2 more
core +2 more sources
Symposium - International Astronomical Union, 1968 A model of solar flares is proposed in which the preflare state comprises a bipolar magnetic-field structure associated with a bipolar photospheric magnetic region. At low heights, the magnetic-field lines are closed but, at sufficiently great heights, the lines are drawn out into an open structure comprising a bipolar flux tube containing a ‘neutral ...
openaire +2 more sources
Diagnostics of the Solar X-Flare Impact on Lower Ionosphere through the VLF-NAA Signal Recordings
Open Astronomy, 2011 An analysis of four solar flare X-ray irradiance effects on VLF signal amplitude and phase delay variations on the NAA/24.0 kHz signal trace during the period from 2005 September to 2006 December was carried out.
Kolarski Aleksandra +2 more
doaj +1 more source
SCATTERING POLARIZATION IN SOLAR FLARES [PDF]
The Astrophysical Journal, 2013 There is an ongoing debate about the origin and even the very existence of a high degree of linear polarization of some chromospheric spectral lines observed in solar flares. The standard explanation of these measurements is in terms of the impact polarization caused by non-thermal proton and/or electron beams.
Jiri Stepan, Petr Heinzel
openaire +3 more sources
Forecasting the Remaining Duration of an Ongoing Solar Flare
Space Weather, 2021 The solar X‐ray irradiance is significantly heightened during the course of a solar flare, which can cause radio blackouts due to ionization of the atoms in the ionosphere.
Jeffrey W. Reep, Will T. Barnes
doaj +1 more source
A Database of Magnetic and Thermodynamic Properties of Confined And Eruptive Solar Flares [PDF]
arXiv, 2023 Solar flares sometimes lead to coronal mass ejections that directly affect the Earth's environment. However, a large fraction of flares, including on solar-type stars, are confined flares. What are the differences in physical properties between confined and eruptive flares?
arxiv
THE SOLAR FLARE IRON ABUNDANCE [PDF]
The Astrophysical Journal, 2012 The abundance of iron is measured from emission line complexes at 6.65 keV (Fe line) and 8 keV (Fe/Ni line) in {\em RHESSI} X-ray spectra during solar flares. Spectra during long-duration flares with steady declines were selected, with an isothermal assumption and improved data analysis methods over previous work.
Kjh Phillips, Brian R. Dennis
openaire +3 more sources
Deep Learning–based Solar Flare Forecasting Model. III. Extracting Precursors from EUV Images
The Astrophysical Journal Supplement Series, 2023 A solar flare is one of the most intense solar activities, and flare forecasting is necessary to avoid its destructive impact on the near-Earth space environment and technological infrastructure.
Dezhi Sun +3 more
doaj +1 more source
A Study of Solar Flare Effects on the Geomagnetic Field Components during Solar Cycles 23 and 24
Atmosphere, 2021 In this paper, we investigated the impact of solar flares on the horizontal (H), eastward (Y) and vertical (Z) components of the geomagnetic field during solar cycles 23 and 24 (SC23/24) using data of magnetometer measurements on the sunlit side of the ...
Oswald Didier Franck Grodji +7 more
doaj +1 more source
Imaging Spectroscopy of a White-Light Solar Flare [PDF]
, 2010 We report observations of a white-light solar flare (SOL2010-06-12T00:57, M2.0) observed by the Helioseismic Magnetic Imager (HMI) on the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI). The HMI data
A. Donea +39 more
core +2 more sources