Search Publications
Stellar flares
Kowalski, Adam F.
Magnetic storms on stars manifest as remarkable, randomly occurring changes of the luminosity over durations that are tiny in comparison to the normal evolution of stars. These stellar flares are bursts of electromagnetic radiation from X-ray to radio wavelengths, and they occur on most stars with outer convection zones. They are analogous to the …
Waves in the lower solar atmosphere: the dawn of next-generation solar telescopes
Stangalini, Marco; Jess, David B.; Jafarzadeh, Shahin +3 more
Waves and oscillations have been observed in the Sun's atmosphere for over half a century. While such phenomena have readily been observed across the entire electromagnetic spectrum, spanning radio to gamma-ray sources, the underlying role of waves in the supply of energy to the outermost extremities of the Sun's corona has yet to be uncovered. Of…
Machine learning in solar physics
Cheung, Mark C. M.; Asensio Ramos, Andrés; Chifu, Iulia +1 more
The application of machine learning in solar physics has the potential to greatly enhance our understanding of the complex processes that take place in the atmosphere of the Sun. By using techniques such as deep learning, we are now in the position to analyze large amounts of data from solar observations and identify patterns and trends that may n…
Extreme solar events
Shibata, Kazunari; Schrijver, Carolus J.; Usoskin, Ilya G. +1 more
We trace the evolution of research on extreme solar and solar-terrestrial events from the 1859 Carrington event to the rapid development of the last twenty years. Our focus is on the largest observed/inferred/theoretical cases of sunspot groups, flares on the Sun and Sun-like stars, coronal mass ejections, solar proton events, and geomagnetic stor…
Surface and interior meridional circulation in the Sun
Hanasoge, Shravan M.
Solar meridional circulation is an axisymmetric flow system, extending from the equator to the poles (
Space weather: the solar perspective: An update to Schwenn (2006)
Temmer, Manuela
The Sun, as an active star, is the driver of energetic phenomena that structure interplanetary space and affect planetary atmospheres. The effects of Space Weather on Earth and the solar system is of increasing importance as human spaceflight is preparing for lunar and Mars missions. This review is focusing on the solar perspective of the Space We…
The evolution of the solar wind
Vidotto, Aline A.
How has the solar wind evolved to reach what it is today? In this review, I discuss the long-term evolution of the solar wind, including the evolution of observed properties that are intimately linked to the solar wind: rotation, magnetism and activity. Given that we cannot access data from the solar wind 4 billion years ago, this review relies on…
Solar force-free magnetic fields
Wiegelmann, Thomas; Sakurai, Takashi
The structure and dynamics of the solar corona is dominated by the magnetic field. In most areas in the corona magnetic forces are so dominant that all non-magnetic forces such as plasma pressure gradients and gravity can be neglected in the lowest order. This model assumption is called the force-free field assumption, as the Lorentz force vanishe…
Solar structure and evolution
Christensen-Dalsgaard, Jørgen
The Sun provides a critical benchmark for the general study of stellar structure and evolution. Also, knowledge about the internal properties of the Sun is important for the understanding of solar atmospheric phenomena, including the solar magnetic cycle. Here I provide a brief overview of the theory of stellar structure and evolution, including t…
Flare-productive active regions
Toriumi, Shin; Wang, Haimin
Strong solar flares and coronal mass ejections, here defined not only as the bursts of electromagnetic radiation but as the entire process in which magnetic energy is released through magnetic reconnection and plasma instability, emanate from active regions (ARs) in which high magnetic non-potentiality resides in a wide variety of forms. This revi…