Results 41 to 50 of about 3,043 (224)
Searching for Rotational X‐Ray Modulation on TIC 277539431
Astronomische Nachrichten, Volume 347, Issue 3, March 2026.ABSTRACT TIC 277539431, a fast rotating M7 dwarf, was detected to host the highest latitude flare to date at 81°$$ {81}^{{}^{\circ}} $$. Magnetic activity like stellar flares occurring at high latitude indicate occurrence of coronal loops at these latitudes on fully‐convective M dwarfs. In contrast, sunspots usually occur below 30°$$ {30}^{{}^{\circ}} $
Desmond Dsouza +2 more
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THE FORMATION OF THE Hα LINE IN THE SOLAR CHROMOSPHERE [PDF]
The Astrophysical Journal, 2012 We use state-of-the-art radiation-MHD simulations and 3D non-LTE radiative transfer computations to investigate \Halpha\ line formation in the solar chromosphere and apply the results of this investigation to develop the potential of \Halpha\ as diagnostic of the chromosphere.
J. Leenaarts +2 more
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Solar mean magnetic field of the chromosphere
Journal of Astrophysics and Astronomy, 2023 The Solar Mean Magnetic Field (SMMF) is the mean value of the line of sight (LOS) component of the solar vector magnetic field averaged over the visible hemisphere of the Sun. So far, the studies on SMMF have mostly been confined to the magnetic field measurements at the photosphere. In this study, we calculate and analyse the SMMF using magnetic field
M. Vishnu, K. Nagaraju, Harsh Mathur
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The Astrophysical JournalThis paper offers a fresh perspective on solar chromosphere heating and plasma outflows, focusing on the contribution of waves generated by solar granulation.
M. Kumar +5 more
doaj +1 more source
Periodic Density Structures Observed in Ulysses Data: First Results
Journal of Geophysical Research: Space Physics, Volume 131, Issue 3, March 2026.Abstract Periodic density structures (PDSs) are advecting quasi‐periodic (periodicities between several minutes and several hours) density enhancements observed in the solar wind and corona. There is strong evidence that PDSs are formed at the Sun.
Brent M. Randol +3 more
wiley +1 more source
Structure of the solar chromosphere [PDF]
Proceedings of the International Astronomical Union, 2004 The chromosphere is an intriguing part of the Sun that has stubbornly resisted all attempts at a comprehensive description. Thus, observations carried out in different wavelength bands reveal very different, seemingly incompatible properties. Not surprisingly, a debate is raging between supporters of the classical picture of the chromosphere as a ...
openaire +2 more sources
Alfvén wave dissipation in the solar chromosphere [PDF]
Nature Physics, 2018 Magneto-hydrodynamic (MHD) Alfvén waves have been a focus of laboratory plasma physics and astrophysics for over half a century. Their unique nature makes them ideal energy transporters, and while the solar atmosphere provides preferential conditions for their existence, direct detection has proved difficult as a result of their evolving and dynamic ...
Samuel D. T. Grant +9 more
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On the Freeze‐In Distance of Solar Wind Fluid Entropy Variability in the Corona
Journal of Geophysical Research: Space Physics, Volume 131, Issue 3, March 2026.Abstract The strong correlation between solar wind entropy and the frozen‐in ion charge state ratio O7+/O6+ ${\mathrm{O}}^{7+}/{\mathrm{O}}^{6+}$ indicates that entropy variability on timescales of hours or longer is preserved from its solar source. This prompts the question: where in the solar atmosphere does this entropy variability come from, and at
Aidan J. Nakhleh +3 more
wiley +1 more source
RADIATING CURRENT SHEETS IN THE SOLAR CHROMOSPHERE [PDF]
The Astrophysical Journal, 2012 An MHD model of a Hydrogen plasma with flow, an energy equation, NLTE ionization and radiative cooling, and an Ohm's law with anisotropic electrical conduction and thermoelectric effects is used to self-consistently generate atmospheric layers over a $50$ km height range.
Goodman, Michael L., Judge, Philip G.
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Space Weather, Volume 24, Issue 3, March 2026.Abstract Solar activity induces ionospheric irregularities that degrade Global Navigation Satellite System (GNSS) performance through amplitude and phase scintillation. Although numerous studies have investigated event‐driven or regional responses, the nonlinear coupling between solar radiation, ionospheric scintillation, and precise point positioning (
Jincheng Li +9 more
wiley +1 more source