Results 51 to 60 of about 941 (201)

Structuring of the quiet solar corona [PDF]

Die Aufheizung der Sonnenkorona, der dünnen äußeren Atmosphäre der Sonne, ist seit Jahrzehnten eine der wichtigsten offenen Fragen der Sonnenphysik. Wie das koronale Plasma oberhalb der viel kühleren Photosphäre Millionen von Grad erreicht, hängt eng mit dem Magnetfeld der Sonne zusammen. Das Feld durchdringt die Sonnenatmosphäre und prägt verschiedene
openaire   +1 more source

Influence of Ionization on the Polytropic Index of the Solar Atmosphere within Local Thermodynamic Equilibrium Approximation

The Astrophysical Journal
An initial theoretical attempt to explain the observed decrease of the polytropic/adiabatic index γ in the solar corona has been accomplished. The chemical reactions of the ionization–recombination processes in local thermodynamic equilibrium (LTE) of a ...
Albert M. Varonov, Todor M. Mishonov
doaj   +1 more source

Solar Energetic Particle Prediction in the Inner Heliosphere Using Deep Learning and PSP/IS⊙IS Data

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 3, June 2026.
Abstract Solar events, such as coronal mass ejections and solar flares, accelerate large numbers of energetic charged particles, producing solar energetic particle (SEP) events that can harm astronauts, damage satellites, and potentially damage infrastructure on Earth.
Tate Hutchins, Spiridon Kasapis, Hameedullah Farooki, Manuel E. Cuesta, Lengying Khoo, Sungmin Pak, Robert Czarnota, Jamie Rankin, Jamey Szalay, Zigong Xu, Georgios Livadiotis, Nikolaos Sarlis, David McComas   +12 more
wiley   +1 more source

Dynamical age of solar wind turbulence in the outer heliosphere

, 1998
In an evolving turbulent medium, a natural timescale can be defined in terms of the energy decay time. The time evolution may be complicated by other effects such as energy supply due to driving, and spatial inhomogeneity.
Matthaeus, William H., Oughton, Sean, William H. Matthaeus, Smith, Charles W., Charles W. Smith, Sean Oughton   +5 more
core   +1 more source

Magnetic Topology and Loop Statistics in Observed Coronal Holes Using Potential Field Modeling

The Astrophysical Journal
Potential field source surface (PFSS) models are widely used to study the solar corona and form the basis for solar wind forecasting, yet they often fail to reproduce observed properties of coronal holes.
Stephan G. Heinemann, Jens Pomoell, Manuela Temmer   +2 more
doaj   +1 more source

Nitric Oxide Radiative Relaxation Time: Damping Timescales of Lower Thermospheric Thermal Perturbations

Geophysical Research Letters, Volume 53, Issue 9, 16 May 2026.
Abstract Nitric oxide (NO) radiative cooling governs much of the energy budget in the Earth's lower thermosphere and damps out temperature perturbations. The radiative relaxation time (RRT), the timescale that defines how efficiently infrared radiation damps out the perturbations to the thermal structure to 1/e of the perturbation's initial value, is ...
Ningchao Wang, Martin G. Mlynczak, John T. Emmert, Manuel López‐Puertas, Bernd Funke   +4 more
wiley   +1 more source

Extreme-ultraviolet bursts and nanoflares in the quiet-Sun transition region and corona [PDF]

, 2021
The quiet solar corona consists of myriads of loop-like features, with magnetic fields originating from network and internetwork regions on the solar surface.
Young, P., L. P. Chitta, Chitta, L., Young, P. R., Peter, H., H. Peter, P. R. Young, Chitta, L. P.   +7 more
core   +1 more source

The Plasma β in Quiet Sun Regions: Multi-instrument View

The Astrophysical Journal
A joint campaign of several spaceborne and ground-based observatories, such as the GREGOR solar telescope, the Extreme-ultraviolet Imaging Spectrometer (EIS), and the Interface Region Imaging Spectrograph (Hinode Observing Plan 381, 2019 October 11–22 ...
Jenny M. Rodríguez-Gómez, Christoph Kuckein, Sergio J. González Manrique, Jonas Saqri, Astrid Veronig, Peter Gömöry, Tatiana Podladchikova   +6 more
doaj   +1 more source

Characterizing Patterns of Resurfacing on Venus With Volcanoes and Coronae

Journal of Geophysical Research: Planets, Volume 131, Issue 5, May 2026.
Abstract One of the major research questions for Venus is the manner in which it resurfaces itself, with a near‐random distribution of a relatively few craters providing the only age constraints for the planet's surface. We use volcanoes and their temporal and spatial relationships to coronae to characterize patterns of coronal resurfacing for ...
Nicholas J. Montiel, Barbara De Toffoli
wiley   +1 more source

Are Heating Events in the Quiet Solar Corona Small Flares? Multiwavelength Observations of Individual Events [PDF]

Solar Physics, 2000
Temporary enhancements of the coronal emission measure in a quiet region have been shown to constitute a significant energy input. Here some relatively large events are studied for simultaneous brightenings in transition region lines and in radio emission. Associated emissions are discussed and tested for characteristics known from full-sized impulsive
Krucker, Sam, Benz, Arnold O.
openaire   +2 more sources