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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…
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…
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…
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…
Multi-viewpoint Coronal Mass Ejection Catalog Based on STEREO COR2 Observations
Vourlidas, Angelos; Stenborg, Guillermo; Balmaceda, Laura A. +1 more
We present the first multi-viewpoint coronal mass ejection (CME) catalog. The events are identified visually in simultaneous total brightness observations from the twin SECCHI/COR2 coronagraphs on board the Solar Terrestrial Relations Observatory mission. The Multi-View CME Catalog differs from past catalogs in three key aspects: (1) all events be…
Chromosphere to 1 AU Simulation of the 2011 March 7th Event: A Comprehensive Study of Coronal Mass Ejection Propagation
de Koning, C. A.; Gombosi, T. I.; Tóth, G. +5 more
We perform and analyze the results of a global magnetohydrodynamic simulation of the fast coronal mass ejection (CME) that occurred on 2011 March 7. The simulation is made using the newly developed Alfvén Wave Solar Model (AWSoM), which describes the background solar wind starting from the upper chromosphere and extends to 24 R⊙. Coupli…
A Multiple Flux-tube Solar Wind Model
Rouillard, Alexis P.; Pinto, Rui F.
We present a new model, MULTI-VP, which computes the three-dimensional structure of the solar wind and includes the chromosphere, the transition region, and the corona and low heliosphere. MULTI-VP calculates a large ensemble of wind profiles flowing along open magnetic field lines that sample the entire three-dimensional atmosphere or, alternativ…
Elongation of Flare Ribbons
Qiu, Jiong; Longcope, Dana W.; Cassak, Paul A. +1 more
We present an analysis of the apparent elongation motion of flare ribbons along the polarity inversion line (PIL), as well as the shear of flare loops in several two-ribbon flares. Flare ribbons and loops spread along the PIL at a speed ranging from a few to a hundred km s-1. The shear measured from conjugate footpoints is consistent wi…
Evidence for a Time Lag in Solar Modulation of Galactic Cosmic Rays
Tomassetti, Nicola; Orcinha, Miguel; Barão, Fernando +1 more
The solar modulation effect of cosmic rays in the heliosphere is an energy-, time-, and particle-dependent phenomenon that arises from a combination of basic particle transport processes such as diffusion, convection, adiabatic cooling, and drift motion. Making use of a large collection of time-resolved cosmic-ray data from recent space missions, …