Solar and Magnetospheric Plasma Theory
Lead Research Organisation:
University of St Andrews
Department Name: Mathematics and Statistics
Abstract
The Solar and Magnetospheric Theory Group (SMTG) of the University of St Andrews will work on the fundamental physical processes occurring in the Sun's atmosphere and planetary magnetospheres. For example: i) Why do sunspots form? ii) Why is the Sun's outer atmosphere (the corona) over 100 times hotter than the visible surface of the Sun? At such high temperatures, the solar gas is ionized (a plasma). iii) Why are there waves in the Sun's atmosphere and what can these waves tell us about the local conditions there? iv) How does the Sun's magnetic field evolve over many years and how does it interact with the Earth? v) How are electrons accelerated during solar magnetic disturbances? vi) What causes aurora? vii) How does a magnetic field change its connections? Many of these key questions require a diverse knowledge base and the SMTG is in an excellent position to answer these questions. We study a wide variety of physical phenomena using mathematical modelling (a combination of fundamental theory, analytical models, computer simulations, forward modelling and observations). It is an integrated approach that is needed, i.e. a mixture of modelling methods and a comparison between observations from several satellite missions and the theoretical models. The topics we will investigate, using plasma theory, are: i) the emergence of new magnetic field from the solar interior, through the solar surface and into the solar atmosphere, ii) the use of Magnetohydrodynamics (MHD) wave theory to deduce properties of the solar atmosphere and magnetic field (coronal seismology), iii) the evolution of the global magnetic field of the solar atmosphere iv) the physical mechanisms responsible for keeping the corona much hotter than the lower parts of the solar atmosphere (coronal heating), v) solar flares and coronal mass ejections, which are the most powerful manifestations of solar magnetic activity and directly affect the Earth, vi) the physics of ultra-low frequency waves in the Earth's magnetosphere and how they contribute to the acceleration of electrons causing the aurora and vii) magnetic reconnection, a process of extreme importance for releasing the immense amount of energy stored in the Sun's magnetised plasma. These phenomena obey physical laws that can be expressed as non-linear partial differential equations. However, what makes them distinct is that different phenomena require different dominant terms. Hence, the physical processes and the plasma response will be different in each case. For example, magnetic reconnection requires electrical resistance but MHD waves in general do not. Gravity is important in flux emergence and prominence formation, but for magnetic reconnection it is not. Particle acceleration in solar flares and the magnetosphere requires a kinetic (particle) description, while many of the others research areas do not. It is the rich complexity of the non-linear equations that makes them hard to solve and to determine what the key physical processes are responsible for each event. A most important research tool is the parallel computer formed by linking many commodity processors together. Then the simulation involves splitting the problem up into smaller parts that run on different processors at the same time (in parallel). Thus, our simulations are completed quicker. Hence, with 256 processors a job requiring 10 years on single machine, is completed in a couple of weeks. We address key issues in the STFC Science Roadmap, especially, how does the Sun affect the Earth? However, a detailed understanding of the physics of our research topics are important not only for the Sun, solar-like stars and space weather, but also for understanding such diverse astrophysical processes such as star formation in giant molecular clouds, the evolution of astrophysical discs around stars, black holes and in Active Galactic Nuclei, and the physics of winds and outflows from stellar to extragalactic scales.
Organisations
Publications
Botha G
(2010)
Thermal conduction effects on the kink instability in coronal loops
in Astronomy & Astrophysics
Archontis V
(2010)
Flux emergence and coronal eruption
in Astronomy and Astrophysics
Mackay D
(2010)
Physics of Solar Prominences: II-Magnetic Structure and Dynamics
in Space Science Reviews
Pascoe D
(2010)
COUPLED ALFVÉN AND KINK OSCILLATIONS IN CORONAL LOOPS
in The Astrophysical Journal
Threlfall J
(2010)
Alfvén wave phase-mixing and damping in the ion cyclotron range of frequencies
in Astronomy & Astrophysics
Russell A
(2010)
Self-consistent ionospheric plasma density modifications by field-aligned currents: Steady state solutions
in Journal of Geophysical Research: Space Physics
Fuentes-Fernández J
(2010)
Magnetohydrodynamics dynamical relaxation of coronal magnetic fields I. Parallel untwisted magnetic fields in 2D
in Astronomy and Astrophysics
McLaughlin J
(2010)
Review Article: MHD Wave Propagation Near Coronal Null Points of Magnetic Fields
in Space Science Reviews
Thornton L
(2010)
Small-Scale Flux Emergence Observed Using Hinode/SOT
in Solar Physics
Russell A
(2010)
Resonant absorption with 2D variation of field line eigenfrequencies
in Astronomy and Astrophysics
Lamb D
(2010)
SOLAR MAGNETIC TRACKING. III. APPARENT UNIPOLAR FLUX EMERGENCE IN HIGH-RESOLUTION OBSERVATIONS
in The Astrophysical Journal
Johnstone C
(2010)
Modelling stellar coronae from surface magnetograms: the role of missing magnetic flux
in Monthly Notices of the Royal Astronomical Society
Archontis V
(2010)
Recurrent solar jets in active regions
in Astronomy and Astrophysics
Parnell C
(2010)
THE DETECTION OF NUMEROUS MAGNETIC SEPARATORS IN A THREE-DIMENSIONAL MAGNETOHYDRODYNAMIC MODEL OF SOLAR EMERGING FLUX
in The Astrophysical Journal
Parnell C
(2010)
Structure of magnetic separators and separator reconnection
in Journal of Geophysical Research: Space Physics
Verwichte E
(2010)
PERIODIC SPECTRAL LINE ASYMMETRIES IN SOLAR CORONAL STRUCTURES FROM SLOW MAGNETOACOUSTIC WAVES
in The Astrophysical Journal
Morton R
(2010)
Propagating magneto-hydrodynamic waves in a cooling homogenous coronal plasma
in Astronomy and Astrophysics
Al-Salti N
(2010)
Three-dimensional solutions of the magnetohydrostatic equations: rigidly rotating magnetized coronae in cylindrical geometry
in Astronomy and Astrophysics
Al-Salti N
(2010)
Three-dimensional solutions of the magnetohydrostatic equations: Rigidly rotating magnetized coronae in spherical geometry
in Astronomy and Astrophysics
Yeates A
(2010)
COMPARISON OF A GLOBAL MAGNETIC EVOLUTION MODEL WITH OBSERVATIONS OF CORONAL MASS EJECTIONS
in The Astrophysical Journal
Yeates A
(2010)
A nonpotential model for the Sun's open magnetic flux
in Journal of Geophysical Research: Space Physics
Haynes A
(2010)
A method for finding three-dimensional magnetic skeletons
in Physics of Plasmas
Smyrli A
(2010)
Trend of photospheric magnetic helicity flux in active regions generating halo coronal mass ejections
in Astronomy and Astrophysics
MacTaggart D
(2010)
SIMULATING THE "SLIDING DOORS" EFFECT THROUGH MAGNETIC FLUX EMERGENCE
in The Astrophysical Journal
Hood A
(2011)
Solar magnetic fields
in Physics of the Earth and Planetary Interiors
Cargill Peter
(2011)
SOLAR PHYSICS Waves galore
in NATURE
Vargas Domínguez S
(2011)
On Signatures of Twisted Magnetic Flux Tube Emergence
in Solar Physics
Browning P
(2011)
Flare particle acceleration and magnetohydrodynamic instabilities
in Plasma Physics and Controlled Fusion
Meyer K
(2011)
Solar Magnetic Carpet I: Simulation of Synthetic Magnetograms
in Solar Physics
Hood A
(2011)
3D MHD Flux Emergence Experiments: Idealised Models and Coronal Interactions
in Solar Physics
McLaughlin J
(2011)
Phase mixing of nonlinear visco-resistive Alfvén waves
in Astronomy & Astrophysics
Harra L
(2011)
The Creation of Outflowing Plasma in the Corona at Emerging Flux Regions: Comparing Observations and Simulations
in Solar Physics
Stark C
(2011)
Contributions to the magnetospheric parallel electric field PARALLEL ELECTRIC FIELD
in Journal of Geophysical Research: Space Physics
Pascoe D
(2011)
PROPAGATING COUPLED ALFVÉN AND KINK OSCILLATIONS IN AN ARBITRARY INHOMOGENEOUS CORONA
in The Astrophysical Journal
Matthews S
(2011)
Solar Particle Acceleration Radiation and Kinetics (SPARK) A mission to understand the nature of particle acceleration
in Experimental Astronomy
Fuentes-Fernández J
(2011)
Magnetohydrodynamics dynamical relaxation of coronal magnetic fields II. 2D magnetic X-points
in Astronomy & Astrophysics
Arregui I
(2011)
Magnetohydrodynamic kink waves in two-dimensional non-uniform prominence threads
in Astronomy & Astrophysics
Wilson F
(2011)
A family of one-dimensional Vlasov-Maxwell equilibria for the force-free Harris sheet
in Physics of Plasmas
Marsh M
(2011)
OBSERVED DAMPING OF THE SLOW MAGNETOACOUSTIC MODE
in The Astrophysical Journal
Hesse M
(2011)
The Diffusion Region in Collisionless Magnetic Reconnection
in Space Science Reviews
Martens P
(2011)
Computer Vision for the Solar Dynamics Observatory (SDO)
in Solar Physics
Mackay D
(2011)
MODELING THE DISPERSAL OF AN ACTIVE REGION: QUANTIFYING ENERGY INPUT INTO THE CORONA
in The Astrophysical Journal
Grady K
(2012)
A systematic examination of particle motion in a collapsing magnetic trap model for solar flares
in Astronomy & Astrophysics
Parnell CE
(2012)
Astrophysical processes on the sun.
in Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
De Moortel I
(2012)
THE EFFECTS OF LINE-OF-SIGHT INTEGRATION ON MULTISTRAND CORONAL LOOP OSCILLATIONS
in The Astrophysical Journal
Fuentes-Fernández J
(2012)
Consequences of spontaneous reconnection at a two-dimensional non-force-free current layer
in Physics of Plasmas
Russell A
(2012)
Magnetosphere-ionosphere waves
in Journal of Geophysical Research: Space Physics
Bushby P
(2012)
Modelling magnetic flux emergence in the solar convection zone
in Astronomy & Astrophysics
Archontis V
(2012)
Magnetic flux emergence and associated dynamic phenomena in the Sun.
in Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
Yeates A
(2012)
CHIRALITY OF HIGH-LATITUDE FILAMENTS OVER SOLAR CYCLE 23
in The Astrophysical Journal
Description | We have investigated a wide variety of plasma physics phenomena in the solar corona, using MHD and kinetic theory. The topics include new research outocmes in MHD waves, MHD instabilities, coronal heating, magnetic reconnection, particle acceleration, flux emergence and other topics. |
Exploitation Route | The results will be used in future research studies to enhance our understanding of plasma processes in the solar corona. |
Sectors | Education,Other |