Results 51 to 60 of about 1,455,996 (195)

Benchmarking Deep Learning Models for Real‐Time Prediction of Post‐Peak Solar Flare Irradiance Using FISM2 Data

Space Weather, Volume 24, Issue 9, September 2026.
Abstract This study presents a deep learning framework for real‐time prediction of post‐peak solar flare irradiance. The model targets the soft X‐ray band (0.1–0.8 nm) and three extreme ultraviolet (EUV) wavelength bands (9.0–9.9 nm, 13.0–13.9 nm, and 30.0–30.9 nm), and produces forecasts at 1‐min cadence for 3 hr after the flare peak.
Jeong‐Heon Kim, Junmu Youn, Sung‐Hong Park, Seungwoo Ahn, Young‐Sil Kwak, Yong‐Jae Moon, P. C. Chamberlin   +6 more
wiley   +1 more source

The ORCA‐TWIN qCMOS Experiment I. Science Case and Commissioning at Calar Alto Observatory

Astronomische Nachrichten, Volume 347, Issue 7, August 2026.
ABSTRACT We describe a pilot study to explore a new generation of fast and low noise CMOS image sensors for time domain astronomy, using two remote telescopes with a baseline of 1635 km. The experiment involves direct imaging with novel qCMOS image sensor technology that combines fast readout with sub‐electron readout noise.
Martin M. Roth, Paško Roje, Stella Vješnica, Stefan Cikota, Alex J. Brown, Mike Kretlow, Marco Azzaro, Santiago Reinhart, Jesús Aceituno, Harry Dawson, Carsten Denker, Torsten Enßlin, Stephan Geier, Thomas Granzer, Thomas Kupfer, Gianluca Li Causi, Samaya Nissanke, José Luis Ortiz, Fernando Pedichini, Katja Poppenhäger, Axel Schwope   +20 more
wiley   +1 more source

HEATING OF THE PARTIALLY IONIZED SOLAR CHROMOSPHERE BY WAVES IN MAGNETIC STRUCTURES [PDF]

The Astrophysical Journal Letters, 2016
ABSTRACT In this paper, we show a “proof of concept” of the heating mechanism of the solar chromosphere due to wave dissipation caused by the effects of partial ionization. Numerical modeling of non-linear wave propagation in a magnetic flux tube, embedded in the solar atmosphere, is performed by solving a system of single-fluid quasi ...
S. Shelyag, E. Khomenko, A. de Vicente, D. Przybylski   +3 more
openaire   +3 more sources

Statistical Study of Geoeffective Fe XV 28.4 nm Emission Bursts and Their Influence on Ionospheric Total Electron Content During the Late Phase of Solar Flares

Journal of Geophysical Research: Space Physics, Volume 131, Issue 7, July 2026.
Abstract Recent studies have demonstrated that warm coronal emissions during the extreme ultraviolet late phase (ELP) of X‐class solar flares can be sufficiently strong to also affect electron density in the Earth's ionosphere. The Fe XV 28.4 nm line was identified as one of the most geoeffective emissions produced during the ELP.
S. Z. Bekker, A. N. O’Hare, H. J. Greatorex, L. A. Hayes, N. Janitzek, G. S. Kerr, R. O. Milligan, L. Qian, K. Watanabe   +8 more
wiley   +1 more source

Magnetoacoustic Portals and the Basal Heating of the Solar Chromosphere

The Astrophysical Journal, 2006
We show that inclined magnetic field lines at the boundaries of large-scale convective cells (supergranules) provide "portals" through which low-frequency ( 5 mHz) acoustic waves, which are believed to provide the dominant source of wave heating of the chromosphere. This result opens up the possibility that low-frequency magnetoacoustic waves provide a
James D. Armstrong, Stuart M. Jefferies, Bernhard Fleck, Alessandro Cacciani, T. J. Bogdan, T. J. Bogdan, Scott W. McIntosh   +6 more
openaire   +2 more sources

The solar chromosphere at high resolution with IBIS [PDF]

Astronomy & Astrophysics, 2009
The structure and energy balance of the solar chromosphere remain poorly known. We have used the imaging spectrometer IBIS at the Dunn Solar Telescope to obtain fast-cadence, multi-wavelength profile sampling of Halpha and Ca II 854.2 nm over a sizable two-dimensional field of view encompassing quiet-Sun network. We provide a first inventory of how the
Cauzzi, G., Reardon, K., Rutten, R.J., Tritschler, A., Uitenbroek, H.   +4 more
openaire   +4 more sources

Simulations Show that Vortex Flows Could Heat the Chromosphere in Solar Plage [PDF]

The Astrophysical Journal Letters, 2020
Abstract The relationship between vortex flows at different spatial scales and their contribution to the energy balance in the chromosphere is not yet fully understood. We perform three-dimensional (3D) radiation-magnetohydrodynamic simulations of a unipolar solar plage region at a spatial resolution of 10 km using the MURaM code. We use
Nitin Yadav, R. H. Cameron, S. K. Solanki   +2 more
openaire   +3 more sources

Identifying and Predicting Coronal Mass Ejection Occurrence: Observational Checklists for Space Weather Forecasters

Space Weather, Volume 24, Issue 6, June 2026.
Abstract Ejections of magnetized plasma from the Sun, known as coronal mass ejections, can drive major geomagnetic activity if Earth‐directed, and are therefore monitored by space weather forecasters. The current focus being the forecast of the arrival time of a coronal mass ejection at Earth and the level of geomagnetic impact.
L. M. Green, A. W. James, N. Ngampoopun, S. L. Yardley, K. Waite, E. K. Mottram, J. Hernandez Camero, J. O'kane   +7 more
wiley   +1 more source

Multi‐Wavelength Transformer‐Based 24‐Hour Solar Flare Forecasting at the Active‐Region Level

Space Weather, Volume 24, Issue 6, June 2026.
Abstract Solar flare forecasting remains challenging due to the complex spatiotemporal evolution of solar active regions (ARs) and the severe class imbalance associated with high‐impact events. In this work, we investigate a transformer‐based framework for active‐region–level solar flare forecasting using short sequences of multi‐wavelength ...
Dunia Alatoom, Nikos Nikolaou
wiley   +1 more source

Magnetic Fields and Plasma Heating in the Sun’s Atmosphere

The Astrophysical Journal
We use the first publicly available data from the Daniel K. Inouye Solar Telescope to track magnetic connections from the solar photosphere into the corona.
P. Judge, L. Kleint, R. Casini, A. G. de Wijn, T. Schad, A. Tritschler   +5 more
doaj   +1 more source