Northumbria University, Department of Mathematics, Physics and Electrical Engineering, 2017
Examination of a fast magnetoacoustic waves, whose solution is obtained analytically using the WKB approximation and progressed along a characteristic using the RK4 method, as it propogates through a region containing a magnetic null point.
Lancaster University, Physics Department, 2018
Examining bulk radial transport and the radial interchange instability at Jupiter and Saturn using JERICHO, a kinetic-ion, fluid-electon hybrid plasma model.
Lancaster University, Physics Department, 2019
Ikuchi is an HTML/Javascript application which uses https://threejs.org/ to render 3D views of solar system magnetospheres.
Published in Monthly Notices of the Royal Astronomical Society, 2019
The propagation of the fast magnetoacoustic wave is studied within a magnetic topology containing a 3D coronal null point whose fan field lines form a dome.
Recommended citation: McLaughlin, J., Thurgood, J., Botha, G. & Wiggs, J. (2019). 3D WKB solution for fast magnetoacoustic wave behaviour within a separatrix dome containing a coronal null point, Monthly Notices of the Royal Astronomical Society, 484(1), pgs 1390–1400. https://doi.org/10.1093/mnras/stz085
Published in Zenodo, 2019
Ikuchi is an HTML/Javascript application which uses https://threejs.org/ to render 3D views of solar system magnetospheres.
Recommended citation: Arridge, C. & Wiggs, J. (2019). Ikuchi: 3D Views of Solar System Magnetospheres, Zenodo https://doi.org/10.5281/zenodo.3451443
Published in Astronomy & Geophysics, 2022
Ikuchi is an HTML/Javascript application which uses https://threejs.org/ to render 3D views of solar system magnetospheres.
Recommended citation: Wiggs, J., Hodnett, R., Walach, M. & Walton, S. (2022). Meandering through the virtual MIST, Astronomy & Geophysics, 63(3), pgs 3.40–3.42. https://doi.org/10.1093/astrogeo/atac0413
Published:
Plasma in the Jovian magnetosphere is removed from Io’s torus mainly via ejection as energetic neutrals and by bulk transport into sink regions in the outer magnetosphere. The physical process generally considered to be responsible for bulk transport is the centrifugal-interchange instability, analogous to the Rayleigh-Taylor instability, but with centrifugal force replacing gravity. This mechanism allows magnetic flux tubes containing hot, tenuous plasma to exchange places with tubes containing cool, dense plasma, moving material from the inner to outer magnetosphere whilst returning magnetic flux to the planet. In order to examine the transport we have developed a full hybrid kinetic-ion, fluid-electron plasma model in 2.5-dimensions, JERICHO. The technique of hybrid modelling allows for probing of plasma motions down to the ion-inertial length scale, considering constituent ion species kinetically as charged particles and forming the electrons into a single magnetised fluid continuum, allowing for insights into particle motions on spatial scales below the size of the magnetic flux tubes. Additionally, JERICHO provides a computational framework capable of capturing a wide range of flow dynamics, up to spatial scales on the order of planetary radii. Results from this model will allow for the examination of bulk transport on spatial scales not currently accessible with state-of-the-art models, improving understanding of mechanisms responsible for moving particles between flux tubes and from the inner to the outer magnetosphere. In this presentation we will examine the latest simulation results from JERICHO, initialised with Jovian parameters.
Published:
JERICHO is a full hybrid kinetic-ion, fluid-electron plasma model in 2.5-dimensions developed for the analysis of bulk transport in the Jovian magnetosphere. Plasma in the Jovian system is removed from Io’s torus mainly via ejection as energetic neutrals and by bulk transport into sink regions in the outer magnetosphere. The physical process generally considered to be responsible for bulk transport is the centrifugal-interchange instability, analogous to the Rayleigh-Taylor instability, but with centrifugal force replacing gravity. This mechanism allows magnetic flux tubes containing hot, tenuous plasma to exchange places with tubes containing cool, dense plasma, moving material from the inner to outer magnetosphere whilst returning magnetic flux to the inner magnetosphere. The technique of hybrid modelling allows for probing of plasma motions from the scale of planetary-radii down to the ion-inertial length scale, considering constituent ion species kinetically as charged particles and forming the electrons into a single magnetised fluid continuum. This allows for insights into particle motions on spatial scales below the size of the magnetic flux tubes. Results from this model will allow for the examination of bulk transport on spatial scales not currently accessible with state-of-the-art models, improving understanding of mechanisms responsible for moving constituent ion species radially outwards from the inner to outer magnetosphere. In this presentation we will examine the structure of the model logic and numerics before analysing the latest results from the model.
Published:
Plasma in the Jovian magnetosphere is removed from Io’s torus mainly via ejection as energetic neutrals and by bulk transport into sink regions in the outer magnetosphere. The physical process generally considered to be responsible for bulk transport is the centrifugal-interchange instability, analogous to the Rayleigh-Taylor instability, but with centrifugal force replacing gravity. This mechanism allows magnetic flux tubes containing hot, tenuous plasma to exchange places with tubes containing cool, dense plasma, moving material from the inner to outer magnetosphere whilst returning magnetic flux to the inner magnetosphere. In order to examine the transport we have developed a full hybrid kinetic-ion, fluid-electron plasma model in 2.5-dimensions, JERICHO. The technique of hybrid modelling allows for probing of plasma motions from the scale of planetary-radii down to the ion-inertial length scale, considering constituent ion species kinetically as charged particles and forming the electrons into a single magnetised fluid continuum. This allows for insights into particle motions on spatial scales below the size of the magnetic flux tubes. Results from this model will allow for the examination of bulk transport on spatial scales not currently accessible with state-of-the-art models, improving understanding of mechanisms responsible for moving particles between flux tubes and from the inner to the outer magnetosphere. In this presentation we will analysis the latest results from the model as well as examining the process of coupling the simulated magnetosphere to a Jovian ionosphere.
Published:
The Jovian magnetosphere is loaded internally with material from the volcanic moon of Io, which is ionised and brought into co-rotation forming the Io plasma torus. Plasma is removed from the torus mainly via ejection as energetic neutrals and by bulk transport into sink regions in the outer magnetosphere.
Published:
Plasma is injected into the magnetospheres of both gas giants in the outer planets from sources located on satellites orbiting them, Io at Jupiter and Enceladus at Saturn. Material ejected from these moons forms tori surrounding their planetary bodies at distances corresponding to the source’s orbit, however these regions are not continually expanding and therefore must have loss mechanisms associated with them. The processes responsible for loss in the two systems are ejection as energetic neutrals and by bulk transport into sink regions in the outer magnetosphere, though the proportion of material removed by these varies. The physical process generally considered to be responsible for bulk transport is the centrifugal-interchange instability, analogous to the Rayleigh-Taylor instability, but with centrifugal force replacing gravity. This mechanism allows magnetic flux tubes containing hot, tenuous plasma to exchange places with tubes containing cool, dense plasma, moving material from the inner to outer magnetosphere whilst returning magnetic flux to the inner magnetosphere. In order to examine the transport we have developed a full hybrid kinetic-ion, fluid-electron plasma model in 2.5-dimensions, JERICHO. The technique of hybrid modelling allows for probing of plasma motions from the scale of planetary-radii down to the ion-inertial length scale, considering constituent ion species kinetically as charged particles and forming the electrons into a single magnetised fluid continuum. This allows for insights into particle motions on spatial scales below the size of the magnetic flux tubes. Results from this model will allow for the examination of bulk transport on spatial scales not currently accessible with state-of-the-art models, improving understanding of mechanisms responsible for moving particles between flux tubes and from the inner to the outer magnetosphere. We have applied JERICHO to both the Jovian and Saturnian systems and this presentation will examine the distribution of ions, current densities and electromagnetic field perturbations, analysing how they evolve both spatially and temporally. This will allow for insights into the radial motions of plasma directed radially outwards, as well as the corresponding response in the associated fields.
Undergraduate laboratories & courses, Lancaster University, Physics Department, 2018
During my PhD studies at Lancaster University, I also possessed the role of Postgraduate Teaching Assistant (PGTA), engaging and participating in the delivery and grading of a number of different undergraduate courses (modules). The primary set of courses that I assisted with was first year practical laboratories (PHYS133-135), in which I was a demonstrator, guiding students on a weekly basis through a range of up to 16 experiments simultaneously, and marked (graded) a number of student’s laboratory books, documenting their progress through the experiment. Additionally, I marked formal written assessments for these courses in the form of complete laboratory reports as well as shorter written analyses of experiments.
Summer Internship, Lancaster University, Physics Department, 2020
A 6 week long summer project undertaken by a second year undergraduate student at Lancaster University and jointly supervised by myself and Chris Arridge. Over the course of the project, the student developed their understanding of general plasma physics and numerical simulation techniques, before being given access to the complete Python codebase of JERICHO (a kinetic-ion, fluid-electron hybrid plasma model for the outer planets). Work was performed using the simulation code to verify the outputs from it reflected those observed in real plasmas, this was done by comparing the drift motions of particles in a variety of set-ups against their analytical solutions. Additionally, analysis of the conservations of fundamental physical properties was performed on the models boundaries to ensure that these were behaving as expected. The project culminated in the student prototyping and implementing a pressure solver that could be incorporated into JERICHO’s codebase.
Summer Internship, Lancaster University, Physics Department, 2021
A 6 week long summer project undertaken by a third year undergraduate student at Lancaster University and jointly supervised by myself and Chris Arridge. Over the course of the project, the student developed their understanding of general plasma physics, numerical simulation techniques and programming in c++. After this the student was provided with access to the complete c++ codebase of JERICHO (a kinetic-ion, fluid-electron hybrid plasma model for the outer planets). The student initially re-enforced their understanding of how to operate the model by setting up a series of single particle drift motion tests and comparing them to their analytic solutions. Work then progressed to the analysis of well-defined instabilities, the one selected for this work was the well-known Rayleigh-Taylor instability. The student constructed initial model configurations that were conducive to the developed of the desired physical effect and the comparison of the results obtained to parameters obtained from analytic theory.