Results 71 to 80 of about 2,789 (225)

Understanding the Variability of Helium Abundance in the Solar Corona Using Three-fluid Modeling and Ultraviolet Observations

The Astrophysical Journal Letters
The variability of helium abundance in the solar corona and the solar wind is an important signature of solar activity, solar cycle, and solar wind sources, as well as coronal heating processes.
Leon Ofman, Yogesh, Silvio Giordano
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

Magneto-thermal Coupling and Coronal Heating in Solar Active Regions Inferred from Microwave Observations

The Astrophysical Journal
The solar corona is much hotter than the photosphere and chromosphere, but the physical mechanism responsible for heating the coronal plasma remains unidentified. The thermal microwave emission, which is produced in a strong magnetic field above sunspots,
Alexey A. Kuznetsov, Gregory D. Fleishman, Gelu M. Nita, Sergey A. Anfinogentov   +3 more
doaj   +1 more source

Polarisation of decayless kink oscillations of solar coronal loops

Nature Communications, 2023
Decayless kink oscillations of plasma loops in the solar corona may contain an answer to the enigmatic problem of solar and stellar coronal heating. The polarisation of the oscillations gives us a unique information about their excitation mechanisms and ...
Sihui Zhong, Valery M. Nakariakov, Dmitrii Y. Kolotkov, Lakshmi Pradeep Chitta, Patrick Antolin, Cis Verbeeck, David Berghmans   +6 more
doaj   +1 more source

Relative Contributions of Lower‐Atmosphere Tidal and Solar‐Magnetospheric Forcings to the Day‐to‐Day Variability of F‐Region Electron Density

Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.
Abstract We use Thermosphere Ionosphere Electrodynamics General Circulation Model simulations nudged to realistic tides and their statistical day‐to‐day variabilities (DTDVs), derived from Michelson Interferometer for Global High‐Resolution Thermospheric Imaging/Ionospheric Connection Explorer observations, to estimate the relative importance of tidal ...
Xian Lu, Jens Oberheide, Deepali Aggarwal   +2 more
wiley   +1 more source

Constraining Coronal Heating: Employing Bayesian Analysis Techniques to Improve the Determination of Solar Atmospheric Plasma Parameters

, 2010
One way of revealing the nature of the coronal heating mechanism is by comparing simple theoretical one dimensional hydrostatic loop models with observations at the temperature and/or density structure along these features. The most well-known method for
Walsh, Robert W., Morton-jones, Anthony J., Adamakis, Sotiris   +2 more
core   +1 more source

The Contribution of the Russell‐McPherron Effect to the Semiannual Variation in Thermospheric Density

Journal of Geophysical Research: Space Physics, Volume 131, Issue 5, May 2026.
Abstract A number of external sources and internal circulation mechanisms have been proposed to explain the well‐known semiannual variation in global mean thermospheric densities. We use the polarity of the Y $Y$‐component (dawn to dusk) of the Interplanetary Magnetic Field (IMF) in the Geocentric Solar Equatorial (GSEQ) frame to identify the influence,
Mike Lockwood, Chris J. Scott, James O’Donoghue, Mat J. Owens, Luke A. Barnard   +4 more
wiley   +1 more source

SYNTHETIC SOLAR CORONAL HEATING ON CURRENT SHEETS

The Astrophysical Journal, 2009
Synthetic heating of solar coronal loops combining Joule and wave-heating mechanisms on current sheets is proposed. The formation of singular current structures such as current sheets can be caused not only by magnetic reconnection and footpoint convection of coronal loops, but also Alfv?n resonance induced by shear flows.
Xiao-Gang Wang, Li-Wen Ren, Jia-Qi Wang, Chi-Jie Xiao   +3 more
openaire   +1 more source

MHD simulations of coronal heating

, 2015
The problem of heating the solar corona requires the conversion of magnetic energy into thermal energy. Presently, there are two promising mechanisms for heating the solar corona: wave heating and nanoflare heating.
Tam, Kuan V.
core  

Coronal Heating by MHD Waves [PDF]

, 2020
The heating of the solar chromosphere and corona to the observed high temperatures, imply the presence of ongoing heating that balances the strong radiative and thermal conduction losses expected in the solar atmosphere. It has been theorized for decades
Farahani, Soheil Vasheghani, Antolin, Patrick, Pascoe, David, Vasheghani Farahani, Soheil, Kolotkov, Dmitrii, Magyar, Norbert, de Moortel, Ineke, Arregui, Iñigo, Srivastava, Abhishek K., Pascoe, David D., Srivastava, Abhishek, Ofman, Leon, Tian, Hui, Guo, Mingzhe, Van Doorsselaere, Tom   +14 more
core   +1 more source