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A New Generation of Standard Solar Models
Basu, Sarbani; Serenelli, Aldo M.; Bergström, Johannes +6 more
We compute a new generation of standard solar models (SSMs) that includes recent updates on some important nuclear reaction rates and a more consistent treatment of the equation of state. Models also include a novel and flexible treatment of opacity uncertainties based on opacity kernels, required in light of recent theoretical and experimental wo…
Coronal mass ejections and their sheath regions in interplanetary space
Pulkkinen, Tuija I.; Koskinen, Hannu E. J.; Kilpua, Emilia
Interplanetary coronal mass ejections (ICMEs) are large-scale heliospheric transients that originate from the Sun. When an ICME is sufficiently faster than the preceding solar wind, a shock wave develops ahead of the ICME. The turbulent region between the shock and the ICME is called the sheath region. ICMEs and their sheaths and shocks are all in…
The Physical Processes of CME/ICME Evolution
Vršnak, Bojan; Lugaz, Noé; Liu, Ying D. +4 more
As observed in Thomson-scattered white light, coronal mass ejections (CMEs) are manifest as large-scale expulsions of plasma magnetically driven from the corona in the most energetic eruptions from the Sun. It remains a tantalizing mystery as to how these erupting magnetic fields evolve to form the complex structures we observe in the solar wind a…
The Interaction of Successive Coronal Mass Ejections: A Review
Temmer, Manuela; Wang, Yuming; Lugaz, Noé +1 more
We present a review of the different aspects associated with the interaction of successive coronal mass ejections (CMEs) in the corona and inner heliosphere, focusing on the initiation of series of CMEs, their interaction in the heliosphere, the particle acceleration associated with successive CMEs, and the effect of compound events on Earth's mag…
The Open Flux Problem
Liu, Y.; Arge, C. N.; Henney, C. J. +9 more
The heliospheric magnetic field is of pivotal importance in solar and space physics. The field is rooted in the Sun’s photosphere, where it has been observed for many years. Global maps of the solar magnetic field based on full-disk magnetograms are commonly used as boundary conditions for coronal and solar wind models. Two primary observational c…
Magnetic Properties of Solar Active Regions That Govern Large Solar Flares and Eruptions
Toriumi, Shin; Harra, Louise K.; Nagashima, Kaori +2 more
Solar flares and coronal mass ejections (CMEs), especially the larger ones, emanate from active regions (ARs). With the aim of understanding the magnetic properties that govern such flares and eruptions, we systematically survey all flare events with Geostationary Orbiting Environmental Satellite levels of ≥M5.0 within 45° from disk center between…
Origins of the Ambient Solar Wind: Implications for Space Weather
Cranmer, Steven R.; Riley, Pete; Gibson, Sarah E.
The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its abilit…
Global Energetics of Solar Flares. V. Energy Closure in Flares and Coronal Mass Ejections
Xu, Yan; Jing, Ju; Warren, Harry P. +11 more
In this study we synthesize the results of four previous studies on the global energetics of solar flares and associated coronal mass ejections (CMEs), which include magnetic, thermal, nonthermal, and CME energies in 399 solar M- and X-class flare events observed during the first 3.5 yr of the Solar Dynamics Observatory (SDO) mission. Our findings…
Origin and Structures of Solar Eruptions I: Magnetic Flux Rope
Cheng, Xin; Guo, Yang; Ding, MingDe
Coronal mass ejections (CMEs) and solar flares are the large-scale and most energetic eruptive phenomena in our solar system and able to release a large quantity of plasma and magnetic flux from the solar atmosphere into the solar wind. When these high-speed magnetized plasmas along with the energetic particles arrive at the Earth, they may intera…
Data-constrained Coronal Mass Ejections in a Global Magnetohydrodynamics Model
Gombosi, T. I.; Tóth, G.; Taktakishvili, A. +6 more
We present a first-principles-based coronal mass ejection (CME) model suitable for both scientific and operational purposes by combining a global magnetohydrodynamics (MHD) solar wind model with a flux-rope-driven CME model. Realistic CME events are simulated self-consistently with high fidelity and forecasting capability by constraining initial f…