Results 81 to 90 of about 1,105,860 (262)

OSCILLATORY RESPONSE OF THE SOLAR CHROMOSPHERE TO A STRONG DOWNFLOW EVENT ABOVE A SUNSPOT [PDF]

, 2016
We report three-minute oscillations in the solar chromosphere driven by a strong downflow event in a sunspot. We used the Fast Imaging Solar Spectrograph of the 1.6 m New Solar Telescope and the Interface Region Imaging Spectrograph (IRIS).
Hannah Kwak, J. Chae, D. Song, Yeon-Han Kim, E. Lim, M. Madjarska   +5 more
semanticscholar   +1 more source

Robust Statistical Techniques for Operational Maintenance of the 10.7 cm Solar Radio Flux

Space Weather, Volume 23, Issue 5, May 2025.
Abstract The F10.7 solar radio flux is a critical quantity for operational space weather nowcasting and forecasting, where it is routinely used as a driver for coupled atmospheric models to estimate a variety of important quantities such as the neutral atmospheric density.
Daniel A. Brandt, Erick F. Vega, Brian J. Thelen   +2 more
wiley   +1 more source

Quasi‐Periodic Pulsations in Ionospheric TEC Synchronized With Solar Flare EUV Emission

Journal of Geophysical Research: Space Physics, Volume 130, Issue 4, April 2025.
Abstract The extreme ultraviolet (EUV) and X‐ray radiation emitted during solar flares has been shown to significantly increase the electron density of the Earth's ionosphere. During flares, quasi‐periodic pulsations in X‐ray flux originating in the corona have previously been linked to subsequent pulsations in the Earth's ionospheric D‐region. Similar
Aisling N. O’Hare, Susanna Bekker, Laura A. Hayes, Ryan O. Milligan   +3 more
wiley   +1 more source

Measurement of Turbulence Injection Scale Down to the Chromosphere

The Astrophysical Journal Letters
The solar atmosphere displays a sharp temperature gradient, starting from spicules in the chromosphere at 2 × 10 ^4 K, outward into the corona exceeding ${10}^{6}$ K.
Zachary Bailey, Riddhi Bandyopadhyay, Shadia Habbal, Miloslav Druckmüller   +3 more
doaj   +1 more source

FORCED FIELD EXTRAPOLATION OF THE MAGNETIC STRUCTURE OF THE Hα FIBRILS IN THE SOLAR CHROMOSPHERE [PDF]

, 2016
We present a careful assessment of forced field extrapolation using the Solar Dynamics Observatory/Helioseismic and Magnetic Imager magnetogram. We use several metrics to check the convergence property.
Xiaoshuai Zhu, Huaning Wang, Z. Du, Han He   +3 more
semanticscholar   +1 more source

Multi‐Source Forecast of Solar Cycle Flare Activity Using the Novel Informer‐Based Models

Space Weather, Volume 23, Issue 4, April 2025.
Abstract Solar flares, the significant indicators of solar activity, have an impact on Earth's satellites and communication systems. Accurate prediction of solar flare events is crucial for mitigating these effects. In this work, we use multiple data sources, including Geostationary Operational Environmental Satellites soft X‐ray flare flux and the ...
Jie Cao, Tingting Xu, Linhua Deng, Miao Wan, Xinhua Zhao, Yang Peng, Xueliang Zhou, Wenhua Wang, Lidong Huang, Wencheng Wang, Lei Yang, Weihong Zhou   +11 more
wiley   +1 more source

First Global Machine Learning Model to Predict the Rate of TEC Index (ROTI) Response to X‐Class Solar Flares

Space Weather, Volume 23, Issue 3, March 2025.
Abstract Solar flares are bursts of electromagnetic radiation originating in the Sun's atmosphere. Solar flares cause a rapid increase in ionization in the ionosphere, resulting in radio signal interference. This paper aims to predict the ionospheric response to the solar flare of various characteristics in all latitudes around the dayside ionosphere ...
A. Mahmoudian, F. Ghorbali, M. Vazifehkhah Hafteh   +2 more
wiley   +1 more source

Structure of the solar chromosphere [PDF]

Proceedings of the International Astronomical Union, 2004
The chromosphere is an intriguing part of the Sun that has stubbornly resisted all attempts at a comprehensive description. Thus, observations carried out in different wavelength bands reveal very different, seemingly incompatible properties. Not surprisingly, a debate is raging between supporters of the classical picture of the chromosphere as a ...
openaire   +2 more sources

OSCILLATION OF NEWLY FORMED LOOPS AFTER MAGNETIC RECONNECTION IN THE SOLAR CHROMOSPHERE [PDF]

, 2016
With the high spatial and temporal resolution Hα images from the New Vacuum Solar Telescope, we focus on two groups of loops with an X-shaped configuration in the dynamic chromosphere.
Shuhong Yang, Yongyuan Xiang
semanticscholar   +1 more source

First Observations of a Geomagnetic Superstorm With a Sub‐L1 Monitor

Space Weather, Volume 23, Issue 3, March 2025.
Abstract Forecasting the geomagnetic effects of solar coronal mass ejections (CMEs) is currently an unsolved problem. CMEs, responsible for the largest values of the north‐south component of the interplanetary magnetic field, are the key driver of intense and extreme geomagnetic activity.
E. Weiler, C. Möstl, E. E. Davies, A. M. Veronig, U. V. Amerstorfer, T. Amerstorfer, J. Le Louëdec, M. Bauer, N. Lugaz, V. Haberle, H. T. Rüdisser, S. Majumdar, M. Reiss   +12 more
wiley   +1 more source