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Related papers: Variations in Finite Difference Potential Fields

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The motion of faint propagating disturbances (PD) in the solar corona reveals an intricate structure which must be defined by the magnetic field. Applied to quiet Sun observations by the Atmospheric Imaging Assembly (AIA)/Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2022-07-20 Huw Morgan , Marianna Korsos

We present a novel numerical approach aiming at computing equilibria and dynamics structures of magnetized plasmas in coronal environments. A technique based on the use of neural networks that integrates the partial differential equations…

Solar and Stellar Astrophysics · Physics 2023-10-30 Hubert Baty , Vincent Vigon

Potential Field Source Surface (PFSS) models are widely used to simulate coronal magnetic fields. PFSS models use the observed photospheric magnetic field as the inner boundary condition and assume a perfectly radial field beyond a ``Source…

Solar and Stellar Astrophysics · Physics 2024-08-30 Luke Fushimi Benavitz , Benjamin Boe , Shadia Rifai Habbal

Parker Solar Probe (PSP) is providing an unprecedented view of the Sun's corona as it progressively dips closer into the solar atmosphere with each solar encounter. Each set of observations provides a unique opportunity to test and…

We perform a numerical parameter study to determine what effect varying differential rotation and flux emergence has on a star's non-potential coronal magnetic field. In particular we consider the effects on the star's surface magnetic…

Solar and Stellar Astrophysics · Physics 2016-03-11 G. P. S. Gibb , D. H. Mackay , M. M. Jardine , A. R. Yeates

The solar corona and young solar wind may be characterized by critical surfaces -- the sonic, Alfv\'en, and first plasma-$\beta$ unity surfaces -- that demarcate regions where the solar wind flow undergoes certain crucial transformations.…

Solar and Stellar Astrophysics · Physics 2019-03-20 Rohit Chhiber , Arcadi V. Usmanov , William H. Matthaeus , Melvyn L. Goldstein

One proposed resolution to the long-standing problem of solar coronal heating involves the buildup of magnetic energy in the corona due to turbulent motions at the photosphere that braid the coronal field, and the subsequent release of this…

Solar and Stellar Astrophysics · Physics 2015-05-27 D. I. Pontin , G. Hornig

The cosmic rays differential intensity inside the heliosphere, for energy below 30 GeV/nuc, depends on solar activity and interplanetary magnetic field polarity. This variation, termed solar modulation, is described using a 2-D (radius and…

Solar and Stellar Astrophysics · Physics 2015-06-12 P. Bobik , G. Boella , M. J. Boschini , C. Consolandi , S. Della Torre , M. Gervasi , D. Grandi , K. Kudela , S. Pensotti , P. G. Rancoita , D. Rozza , M. Tacconi

The photospheric magnetic field vector is continuously derived from measurements, while reconstruction of the three-dimensional (3D) coronal magnetic field requires modelling with photospheric measurements as a boundary condition. For…

Solar and Stellar Astrophysics · Physics 2022-03-23 I. Chifu , B. Inhester , T. Wiegelmann

Force-free extrapolations are widely used to study the magnetic field in the solar corona based on surface measurements. The extrapolations assume that the ratio of internal energy of the plasma to magnetic energy, the plasma-beta is…

Solar and Stellar Astrophysics · Physics 2015-11-25 H. Peter , J. Warnecke , L. P. Chitta , R. H. Cameron

The enrichment of coronal loops and the slow solar wind with elements that have low First Ionisation Potential, known as the FIP effect, has often been interpreted as the tracer of a common origin. A current explanation for this FIP…

Solar and Stellar Astrophysics · Physics 2021-01-06 Victor Réville , Alexis P. Rouillard , Marco Velli , Andrea Verdini , Éric Buchlin , Michaël Lavarra , Nicolas Poirier

The role of interchange reconnection as a drive mechanism for the solar wind is explored by solving the global magnetic-field-aligned equations describing wind acceleration. Boundary conditions in the low corona, including a…

Solar and Stellar Astrophysics · Physics 2023-08-16 J. F. Drake , S. D. Bale , M. Swisdak , N. E. Raouafi , M. Velli

The Optimal Power Flow (OPF) problem is pivotal for power system operations, guiding generator output and power distribution to meet demand at minimized costs, while adhering to physical and engineering constraints. The integration of…

Machine Learning · Computer Science 2023-11-27 Chen Li , Alexander Kies , Kai Zhou , Markus Schlott , Omar El Sayed , Mariia Bilousova , Horst Stoecker

Remote and in-situ observations strongly imply that the slow solar wind consists of plasma from the hot, closed-field corona that is released onto open magnetic field lines. The Separatrix Web (S-Web) theory for the slow wind proposes that…

Solar and Stellar Astrophysics · Physics 2017-05-26 A. K. Higginson , S. K. Antiochos , C. R. DeVore , P. F. Wyper , T. H. Zurbuchen

The solar magnetic structure changes over the solar cycle. It has a dipole structure during solar minimum, where the open flux extends mainly from the polar regions into the interplanetary space. During maximum, a complex structure is…

Solar and Stellar Astrophysics · Physics 2023-06-28 Minami Yoshida , Toshifumi Shimizu , Shin Toriumi

Solar flares fall into two types with eruptive ones associated with coronal mass ejection (CME) and confined ones without CME. To explore whether there are pre-flare conditions in terms of magnetic energy and helicity that can effectively…

Solar and Stellar Astrophysics · Physics 2023-03-29 Aiying Duan , Chaowei Jiang , Xueshang Feng

In this paper, we simulate the magnetic flux evolution at different heliocentric distances during two solar-maximum Carrington rotations (CRs) using the time-evolving coronal magnetohydrodynamic (MHD) model COCONUT to investigate the ``open…

The relationship between moderate and extremely high levels of geomagnetic activity, represented by the Kp index (2- to 5+ and 6- to 9), and solar wind conditions during southward IMF intervals was revealed utilizing a newly developed…

Space Physics · Physics 2025-09-03 Ryozo Kitajima , Motoharu Nowada , Ryotaro Kamimura

We review our state of knowledge of coronal element abundance anomalies in the Sun and stars. We concentrate on the first ionization potential (FIP) effect observed in the solar corona and slow-speed wind, and in the coronae of solar-like…

Solar and Stellar Astrophysics · Physics 2015-09-30 J. Martin Laming

In a previous work, Ulysses data was analyzed to build a complete axisymmetric MHD solution for the solar wind at minimum including rotation and the initial flaring of the solar wind in the low corona. This model has some problems in…

Astrophysics · Physics 2007-05-23 A. Aibeo , J. Lima , C. Sauty