Results 91 to 100 of about 41,536 (207)

A model for the formation of the active region corona driven by magnetic flux emergence

, 2014
We present the first model that couples the formation of the corona of a solar active region to a model of the emergence of a sunspot pair. This allows us to study when, where, and why active region loops form, and how they evolve.
Bingert, S., Chen, F., Cheung, M. C. M., Peter, H.   +3 more
core   +1 more source

The average solar wind in the inner heliosphere: Structures and slow variations [PDF]

, 1983
Measurements from the HELIOS solar probes indicated that apart from solar activity related disturbances there exist two states of the solar wind which might result from basic differences in the acceleration process: the fast solar wind (v 600 kms(-)1 ...
Schwenn, R.
core   +1 more source

Direct Measurements of Magnetic Twist in the Solar Corona

, 2012
In the present work we study evolution of magnetic helicity in the solar corona. We compare the rate of change of a quantity related to the magnetic helicity in the corona to the flux of magnetic helicity through the photosphere and find that the two ...
A. Malanushenko, Alissandrakis, Aschwanden, Burnette, Chae, D. W. Longcope, DeRosa, Finn, Georgoulis, Lim, Longcope, Longcope, M. H. Yusuf, Malanushenko, Malanushenko, Park, Pearson, Pevtsov, Prautzsch, Press, Welsch, Welsch, Welsch   +22 more
core   +1 more source

A model for heating the super-hot corona in solar active regions

Nature Astronomy
What physical mechanisms heat the outer solar or stellar atmosphere to million-Kelvin temperatures is a fundamental but long-standing open question. In particular, the solar corona in active region cores contains an even hotter component reaching ten million Kelvin, manifesting as persistent coronal loops in extreme ultraviolet and soft X-ray images ...
Zekun Lu, Feng Chen, M. D. Ding, Can Wang, Yu Dai, Xin Cheng   +5 more
openaire   +2 more sources

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

Modelling the total solar eclipse in 2024 with COCONUT

Astronomy & Astrophysics
Context. Coronal modelling is crucial for a better understanding of solar physics and heliophysics. Accurate plasma conditions at the outer boundary of a solar corona lead to more precise space weather predictions.
Baratashvili T., Wang H. P., Sorokina D., Lani A., Poedts S.   +4 more
doaj   +1 more source

Temporal Behavior and Latitudinal Relationships between Key Solar Parameters and Green Line Emissions in the Solar Corona

The Astrophysical Journal Letters
Understanding the link between solar parameters and their influence on green line emissions would help unravel the complexities of eruptive phenomena within the solar corona. This study explores the intricate relationship between green line emissions and
Jacob Oloketuyi, Yu Liu, Linhua Deng, Abouazza Elmhamdi, Khaled Nasser Almosabeh, Fengrong Zhu, Haitang Li, Feiyang Sha, Qiang Liu, Oladipo Emmanuel Abe, Charles Owolabi, Olufemi Olusola   +11 more
doaj   +1 more source

A Near-half-century Simulation of the Solar Corona

The Astrophysical Journal Letters
We present an overview of results from a magnetofrictional model of the entire solar corona over a period of 47 yr. The simulation self-consistently reproduces decades of solar phenomena, varying in duration between rapid eruptions and the long-term ...
Valentin Aslanyan, Karen A. Meyer, Roger B. Scott, Anthony R. Yeates   +3 more
doaj   +1 more source

131 and 304 Å Emission Variability Increases Hours Prior to Solar Flare Onset

The Astrophysical Journal Letters
Thermal changes in coronal loops are well studied, both in quiescent active regions and in flaring scenarios. However, relatively little attention has been paid to loop emission in the hours before the onset of a solar flare; here, we present the ...
Kara L. Kniezewski, E. I. Mason, Vadim M. Uritsky, Seth H. Garland   +3 more
doaj   +1 more source

Dynamic Temperature Structure of the Corona [PDF]

, 2012
The solar corona is heated to million degrees and information about the temperature structure is a key to understand the heating mechanisms. Although it is not easy to measure, the temperature looks to be remarkably steady in the solar corona and in ...
REALE, Fabio
core