Results 91 to 100 of about 14,964 (204)

On chromospheric heating during flux emergence in the solar atmosphere

, 2017
Context. The radiative losses in the solar chromosphere vary from 4~kW~m$^{-2}$ in the quiet Sun, to 20~kW~m$^{-2}$ in active regions. The mechanisms that transport non-thermal energy to and deposit it in the chromosphere are still not understood.
Carlsson, Mats, Danilovic, Sanja, Leenaarts, Jorrit, Rodríguez, Jaime de la Cruz, Scharmer, Göran   +4 more
core   +1 more source

Decent Estimate of CME Arrival Time From a Data‐Assimilated Ensemble in the Alfvén Wave Solar Atmosphere Model (DECADE‐AWSoM)

Space Weather, Volume 23, Issue 1, January 2025.
Abstract Forecasting the arrival time of Earth‐directed coronal mass ejections (CMEs) via physics‐based simulations is an essential but challenging task in space weather research due to the complexity of the underlying physics and limited remote and in situ observations of these events. Data assimilation techniques can assist in constraining free model
Hongfan Chen, Nishtha Sachdeva, Zhenguang Huang, Bart van der Holst, Ward Manchester IV, Aniket Jivani, Shasha Zou, Yang Chen, Xun Huan, Gabor Toth   +9 more
wiley   +1 more source

Fast magnetic reconnection in the solar chromosphere mediated by the plasmoid instability

, 2015
Magnetic reconnection in the partially ionized solar chromosphere is studied in 2.5-dimensional magnetohydrodynamic simulations including radiative cooling and ambipolar diffusion.
Kliem, Bernhard, Lin, Jun, Ni, Lei, Wu, Ning   +3 more
core   +1 more source

Seismic Emissions from a Highly Impulsive M6.7 Solar Flare

, 2008
On 10 March 2001 the active region NOAA 9368 produced an unusually impulsive solar flare in close proximity to the solar limb. This flare has previously been studied in great detail, with observations classifying it as a type 1 white-light flare with a ...
A. Kosovichev, A.-C. Donea, A.-C. Donea, A.-C. Donea, A.-C. Donea, C. Lindsey, D. Besliu-Ionescu, H. Moradi, H. Moradi, J. Aboudarham, J. C. Martínez-Oliveros, J.C. Martínez-Oliveros, J.J. Sudol, J.P. Li, M. Aschwanden, M.D. Ding, M.E. Machado, R. Chandra, S.P. Rajaguru, V.V. Zharkova, V.V. Zharkova, V.V. Zharkova, W. Uddin, Y. Liu   +23 more
core   +3 more sources

Magnetic fields of an active region filament from full Stokes analysis of Si I 1082.7 nm and He I 1083.0 nm

, 2012
Vector magnetic fields of an active region filament in the photosphere and upper chromosphere are obtained from spectro-polarimetric observations recorded with the Tenerife Infrared Polarimeter (TIP II) at the German Vacuum Tower Telescope (VTT).
A. Lagg, Asensio Ramos, Canou, Centeno, Collados, Georgoulis, Guo, Harvey, Kurucz, Lagg, Leroy, Lin, Lites, Lites, López Ariste, Merenda, Okamoto, Paletou, Rüedi, S. Solanki, Sasso, Socas-Navarro, Solanki, Trujillo Bueno, Wang, Y. Liu, Z. Xu   +26 more
core   +1 more source

Hall instability of solar flux tubes

, 2012
The magnetic network which consists of vertical flux tubes located in intergranular lanes is dominated by Hall drift in the photosphere-lower chromosphere region ($\lesssim 1 Mm$).
Pandey, B. P., Wardle, Mark
core   +1 more source

Bidirectional outflows as evidence of magnetic reconnection leading to a solar microflare

, 2016
Magnetic reconnection is a rapid energy release process that is believed to be responsible for flares on the Sun and stars. Nevertheless, such flare-related reconnection is mostly detected to occur in the corona, while there have been few studies ...
Cao, Wenda, Chen, Feng, Cheng, Xin, Ding, M. D., Fang, Cheng, Hong, Jie, Li, Ying, Yang, Kai   +7 more
core   +1 more source

Chromospheric and Coronal Spectra [PDF]

Highlights of Astronomy, 1995
The interpretation of chromospheric and coronal spectra requires accurate ionization and recombination rates, collision strengths and transition probabilities. Recent projects to improve calculations of opacities in stellar interiors have led to a large amount of new atomic data.
openaire   +3 more sources

Emergence of granular-sized magnetic bubbles through the solar atmosphere. II. Non-LTE chromospheric diagnostics and inversions

, 2015
Magnetic flux emergence into the outer layers of the Sun is a fundamental mechanism for releasing energy into the chromosphere and the corona. In this paper, we study the emergence of granular-sized flux concentrations and the structuring of the ...
Bellot-Rubio, Luis, Hansteen, Viggo, Ortiz, Ada, Rodríguez, Jaime de la Cruz   +3 more
core   +1 more source

Stellar model chromospheres. IX - Chromospheric activity in dwarf stars

The Astrophysical Journal, 1979
High-resolution Ca II K line profiles are used to model the upper photospheres and lower chromospheres of eight main-sequence stars ranging in spectral type from F0 to M0 and exhibiting different degrees of chromospheric activity. The model chromospheres are studied as a function of spectral type and activity for stars of similar spectral type in order
W. L. Kelch, S. P. Worden, J. L. Linsky
openaire   +1 more source