Back up of STFC PhD Projects 2023

Available PhD projects in astrophysics, space plasma and solar physics of our STFC studentships 2023 are listed below.

Our STFC studentships starting in September 2023 are open for the application for the following research projects until 31st January 2023.

For more information on the application process, please visit the UCL Graduate Degrees pages and read the "guidelines for research programmes" carefully. To apply, please visit the Online Application page. Please choose full-time or part-time and then click "Apply for this course". Please make sure that you are applying for "Research Degree: Space and Climate Physics" and the course code of "RRDSPSSING01".

Entry requirements

An upper second-class Bachelor’s degree, or a second-class Bachelor’s degree together with a Master's degree from a UK university in a relevant subject, or an equivalent overseas qualification.

Additional eligibility requirements

The STFC studentship will pay your full tuition fees and a maintenance allowance for 3.5 years (subject to the PhD upgrade review).

Astrophysics

Effect of Particle Traps on the Disk Chemistry and the Future Composition of Planets

Supervisor: Dr. Paola Pinilla

Recent observations of protoplanetary disks reveal that substructures in the dust distribution of protoplanetary disks are common. These substructures show different forms, prevalence, locations, scales, and amplitudes around stars with different properties, such stellar luminosity and age (Andrews 2020). Although planet-disk interaction is a popular explanation for the origin of these structures, there are several theoretical alternatives and currently the real origin remains unknown (Pinilla & Youdin 2017), and planets have been only found in one protoplanetary disk (Keppler et al., 2018). The purpose of this project is to use chemical models together with hydrodynamical and dust evolution models as crucial keys to differentiate between all these models for the origin of the observed substructures. This research is timely with the recent data from ALMA (MAPS large program, http://alma-maps.info/), which maps the chemical structures (around 25 atomic and molecular lines), and constrain the properties of the gas reservoirs on planet-forming scales, in a variety of protoplanetary disks.
Parametric studies of disk chemistry with simple prescriptions of gas and dust have shown that depletions of dust and gas make those parts of the disk more transparent to stellar and external radiation (UV and X-rays), and therefore these regions become warmer. This will have a direct influence on the locations of the ice lines of different abundant volatiles, such as water and carbon-monoxide, and as a consequence it will also affect the composition of the planets forming within these disks. Contrary, the regions where particles concentrate, the disk temperature decrease and some volatiles are sequestered in the grains (Facchini et al., 2018, Alarcón et al., 2020). Current chemical models have only explored in detail the case of planet-disk interaction with several simplifications. In this thesis, we will explore the effect of different origins of pressure bumps in the disk, including planets, dead zones, zonal flows, and vortices. We aim to understand how the nature of such pressure bumps (when they form, how long they live, amplitude, location) affects the gas and dust distribution, the disk temperature and the chemical abundances of several volatiles in protoplanetary disks. We place interest on particular atomic and molecular lines. For instance, the carbon-to-oxygen ratio is one of the few planetary properties which can provide useful information on the formation history of a planet and it can be measure both in planets and disks (e.g., Madhusudhan et al., 2012, Bergin et al., 2016).

Desired Knowledge and Skills

Undergraduate in astrophysics
Strong computational skills
(Optional) Background on chemistry

Probabilistic deep learning for cosmology and beyond

Supervisor: Prof. Jason McEwen

The current evolution of our Universe is dominated by the influence of dark energy and dark matter, which constitute 95% of its content. However, an understanding of the fundamental physics underlying the dark Universe remains critically lacking. Forthcoming experiments have the potential to revolutionalise our understanding of the dark Universe. Both the ESA Euclid satellite and the Rubin Observatory Legacy Survey of Space and Time (LSST) will come online imminently, with Euclid scheduled for launch in 2023 and the Rubin LSST Observatory having recently achieved first light. Furthermore, the Simons Observatory is in advanced stages of construction. Sensitive statistical and deep learning techniques are required to extract cosmological information from weak observational signatures of dark energy and dark matter.
The classical approach of deep learning is to make single predictions. A single estimate of a quantity of interest, such as an image, is typically made. For robust scientific studies, however, single estimates are not sufficient and a principled statistical assessment is critical in order to quantify uncertainties. Bayesian inference provides a principled statistical framework in which to perform scientific analyses. In cosmology, in particular, Bayesian inference is the bedrock of most cosmological analyses. While such approaches provide a complete statistical interpretation of observations, which is critical for robust and principled scientific studies, they are typically computationally slow, in many cases prohibitively so. Furthermore, in such analyses prior information typically cannot be injected by a deep data-driven approach.
In the proposed project we will develop probabilistic deep learning approaches, where probabilistic components are incorporated as integral components of deep learning models. Similarly, we will also develop statistical analysis techniques for which deep learning components are incorporated as integral components. This deep hybrid approach, where statistical and deep learning components are tightly coupled in integrated approaches, rather than considered as add-ons, will allow us to realise the complementary strengths of these different approaches simultaneously.
Specifically, we will develop novel probabilistic deep learning models, variational inference techniques and simulation-based inference approaches. These new methodologies will be applied to various cosmological problems and probes, focusing on the cosmic microwave background and weak gravitational lensing, and will include generative models for emulation and inference approaches for the estimation of not only the parameters of cosmological models but also to assess the most effective models and physical theories for describing our Universe.
The student should have a strong mathematical background and be proficient in coding, particularly in Python. The student will gain extensive expertise during the project in deep learning, going far beyond the straightforward application of existing deep learning techniques, instead focusing on the construction on novel probabilistic deep learning approaches and their application to novel problems in cosmology and beyond. The expertise gained in foundational deep learning will prepare the student well for a future career either in academia or industry. In particular, the emerging field of probabilistic deep learning is a speciality highly sought after in industry by many companies, such as Google/DeepMind, Facebook, Amazon and many others.

Desired Knowledge and Skills

Undergraduate in physics, mathematics, computer science or statistics (or related field)
Strong computational skills
Strong mathematical skills
Some background in astrophysics is desirable but not essential
Some background in machine learning is desirable but not essential

Euclid Weak Lensing

Supervisor: Prof. Thomas Kitching

Euclid is an ESA/NASA mission that will launch in 2023. It will survey 3/4 of the extragalactic sky, back in time over 10 billion years, resulting in a Petabyte scale data set of Billions of galaxies. Euclid is designed and built around a technique called weak lensing - that is the distorting, gravitational lensing effect caused by dark matter on the images of every galaxy. In MSSL we lead the weak lensing analysis in Euclid and built the Euclid VIS Instrument (the largest full-image camera ever launched for astronomy). This PhD project is to work on and lead part of the weak lensing analysis for Euclid; a unique and historically important opportunity to be at the heart of a new and transformative mission that will change our view of Universe. Specifically, the work will be to develop and integrate validation tests of the data, including measurements of the distance-redshift relation, that can be used both to demonstrate that the data is robust and also be used to determine cosmological parameters. These tests will then be incorporated into the primary cosmological analysis pipelines, that will then be used to explore deviations from Einstein’s general relativity in cosmological scales.

Desired Knowledge and Skills

Undergraduate in astrophysics
Strong computational skills
Strong mathematical skills

Linking exoplanet detection to formation: population synthesis

Supervisor: Dr. Vincent Van Eylen

The possibility of planets orbiting other stars has been a topic of fascination for centuries. We are the first generation that has brought these planets – now known as exoplanets – from the realm of science-fiction into that of science. An important milestone was the discovery of several planets orbiting a pulsar (Wolszczan & Frail, 1992), followed by the first planet orbiting a star more similar to our Sun (Mayor & Queloz, 1995), an achievement awarded the 2019 Nobel Prize in Physics. The 25 years since have been filled with an abundance of exciting discoveries and today we know over 4000 exoplanets. These planets exhibit an incredible diversity of properties. Why do so many planets have tiny orbits – often much smaller than that of Mercury? What causes planets to become rocky, gaseous, or something in between? Why do some planets have orbits that are strongly eccentric, or misaligned with the rotation of their host stars? What happens to planets when stars evolve away from the main sequence? Which planets are the most favourable and interesting targets for studies of their atmospheres? How unique is our solar system – are we alone?
Exoplanet science is a young field of research and there is great potential for many ground-breaking new discoveries. A PhD project is available that will seek to link the discovery of thousands of exoplanets to planet formation models, in what is known as population synthesis modelling. Over the next years, the number of known exoplanets is expected to double or even triple, powered by progress in complementary observing techniques such as transit measurements, radial velocity observations, directly imaged exoplanets, microlensing data, and forthcoming astrometric planet detections. During this PhD project, we will attempt to link simulated planet population synthesis models to the observed picture of planet architecture, demographics, and host star properties, to test the underlying physics of planet formation.
During this project a motivated student will sharpen their analytical background and physical knowledge, while developing strong data science skills that will be valuable both in an academic career and outside of academia. Furthermore, there will be ample opportunity to travel to other universities and present new findings in international conferences, as well as the potential to conduct novel observations at telescopes around the world.

Desired Knowledge and Skills

Undergraduate in astrophysics, planetary science, computer science, or related degree.
A background in physics and/or data science is helpful but lack thereof can be overcome with strong motivation. Alternatively, a motivated student with a strong background in computer science or data science rather than astrophysics will also be considered.
Excellent writing and presentation skills are a bonus, as is evidence of motivation, leadership and creativity.

Multi-messenger astrophysics of gravitational wave sources containing a neutron star

Supervisor: Prof. Kinwah Wu

The direct detection of gravitational waves (GW) emitted by compact objects confirmed a key prediction of general relativity and opened up new opportunities for investigating astrophysics in extreme environments. The discovery of the electromagnetic (EM) counterpart of the GW source GW170817, a merger of two neutron stars, firmly established the viability of time-domain multi-messenger study of extreme relativistic systems. GW sources are inhomogeneous classes of objects, with frequencies/wavelengths of their GW determined by the size of the sources. This project investigates the multi-messenger astrophysics of black hole – neutron star, neutron star – neutron star and/or neutron star – white dwarf binaries, which are GW sources. The presence of at least one neutron star in the systems implies that these systems emit EM radiation. For instance, the EM radiation from compact neutron star – white dwarf systems span from radio to gamma-ray wavelengths. Some systems emit also non-photonic particles. An example is those involving the disruption of a neutron star. The disruption of neutron star in the merging process would lead to a rapid change in density and pressure, forcing the neutron star material to undergo a hadronic phase transition, and leptons and neutrinos will be produced. An option of the project is to investigate the hadronic phase transition that leads to emission of the gamma-ray and neutrinos, with their timing properties in reference to the GW signals. Another option is to investigate general relativistic transport of photon and non-photon particles in these mergers, to be detected by the LIGO/KAGRA/ET/LISA GW experiments and the space gamma-ray observatories.

Desired Knowledge and Skills

Have coding experience. Knowledge in gravitational wave physics.
Creative and critical thinking.
Strong undergraduate training in physics/astrophysics and in mathematical methods.
Comfortable with both analytical and numerical calculations.

Building Better Milky Way Models

Supervisor: Dr. Ralph Schoenrich

Galactic astronomy, which studies of our Milky Way Galaxy, is experiencing a revolutionary increase in available data. These surveys are mapping the positions, motions, and properties (e.g. age and composition, which tell us when and where a star was born) of Milky Way stars. This allows us to reveal the structure, dynamics and history of our Milky Way, and infer how disc/spiral galaxies work in general. At the centre of this effort is the Gaia satellite mission, which is mapping the positions and motions of more than a billion stars in an area covering a whole quadrant of the Milky Way. To illustrate this progress: the predecessor of Gaia, Hipparcos, mapped about 100k stars in a region that covers only about one 50^th of our distance to the Galactic Centre. In short, right now we can for the first time really map a major part of our galaxy. In addition, ground-based follow-up missions are taking millions of stellar spectra to help us get very precise elemental compositions and parameters for a subset of these stars.
This flood of data requires a lot of models to understand what we are measuring. The MSSL/UCL galaxy group has unique competence in these models and their use in interpreting the data. We have experience in simulations, analytical modelling, and Bayesian/machine learning inference. With these we can map the dark matter content of the Milky Way, constrain the nature of dark matter by mapping the resonances of the Galactic bar in the disc, and build chemo-dynamical models that explore the history of the Milky Way, e.g. for mergers. Particular innovations that this group has pioneered are unbiased stellar distances and parameters. These have allowed us to constrain models for the slowing of the Milky Way’s galactic bar, which have for the first time provided strong evidence for the present inertial mass of dark matter in the Galactic halo; further the first measurement of radial migration, the determination of the solar motion (I.e. where we are moving), and explorations of the warp in the Milky Way disc. In the past years, the research has focused on mostly stellar motions alone, but similar to the use of Hipparcos data, we can expect that in the next years, the focus will shift to combining chemistry with stellar motions.
The focus of the project is on making use of the combined chemical and kinematic data from these missions. The project is to refine existing chemo-dynamical models for the Milky Way by directly challenging them with the new data. The first background models can be used to explore the migration of stars in the Galactic disc and then use those (consistent models) to map the gravitational potential of the Milky Way and (by comparison) map out the dark matter content of the Galaxy. As we found in the past years, these models need to be modified by the expected perturbation from the Milky Way’s galactic bar and spiral arms, which create resonances in the Galactic disc that can be quantified by stream-like structures observed in the stellar motions in the disc. A particular focus is on exploring the interaction of these structures: so far the (slowing) galactic bar, and radial migration of stars driven mainly by the spiral patterns have been modelled separately. However, we know that the bar’s presence will affect the spiral patterns in the Milky Way, imposing limitations on their effects on the Galactic disc, as well as their effects are altered by the superposition of different resonances created by the coexisting patterns. As a benefit, we will obtain i) corrected maps of the Galactic potential, ii) independent constraints from the resonant structure, iii) an improved history of the Galactic disc and origin of the Sun, iv) more precise information on the nature of dark matter residing in the Galaxy.
To achieve this, we use tailored N-body simulations, analytical models, and advanced data analysis. Depending on the skills and preferences of the student, the project can be taken more in a direction of data analysis, refining the stellar parameters, to more theory-dominated studies of resonant dynamics in the disc, or more balanced combinations of both.

Desired Knowledge and Skills

Undergraduate studies in physics, astrophysics, or related fields
Strong analytical skills, programming skills desirable (but not required)

Working out mountains and valleys inside neutron stars

Supervisor: Prof. Silvia Zane

Neutron stars, the remnant of massive stars, are extreme objects. They are characterized by strong gravity and hosts large magnetic fields, the larger magnets known in the cosmo. The interior of the neutron star, where matter reaches supranuclear densities, is poorly understood and to arrive at its description is one of the holy grail of compact objects astrophysics today. In particular, the density stratification in the neutron star crust and envelope can be largely affected by strong magnetic stresses that may result in a non axisymmetric distribution of matter. Would this be the case, then the neutron star will behave as a rotating body with a substantial non zero quadrupole mass moment, that may result in the emission of detectable gravitational waves (GW). This project will investigate this scenario, making use of numerical methods to infer the density distribution of the star, with the goal to make prediction for the signal detectability with the LIGO/KAGRA/ET/LISA GW experiments and/or the space gamma-ray observatories.

Desired Knowledge and Skills

Have solid coding experience (essential).
Knowledge in neutron star interior and gravitational wave physics.
Creative and critical thinking.
Strong undergraduate training in physics/astrophysics and in mathematical methods.
Comfortable with both analytical and heavy numerical calculations.

Planetary Science

The effects of climate change on terrestrial extreme environments and implications for the habitability of other planetary bodies

Supervisor: Dr. Louisa Preston

Changes to Earth’s climate, driven by increased human emissions of heat-trapping greenhouse gases, are already having widespread effects on the environment. Particular changes such as rising temperatures, longer more pronounced heat waves and droughts are greatly impacting the planet, not least the environments, and the life they contain, that were already considered extreme by our standards. Many of these environments are now starting to resemble those we observe on other planetary bodies, especially Mars, a planet which itself has undergone global climatic change. This PhD project will study extreme environments on the Earth undergoing climatic changes - using orbital imagery and in-situ sample analysis - to understand the chemical, mineralogical and biological effects of climate change, and the implications of this to understanding the habitability potential of similar sites on Mars.

Desired Knowledge and Skills

Undergraduate in geology/planetary science
Experience in GIS/planetary imaging/ENVI
Experience in mineralogy

The Many Influences on Comets’ Tails

Supervisor: Prof. Geraint Jones

Comets’ icy nuclei, typically measuring only a few kilometres across, carry invaluable information on the origins of our Solar System. In addition, the processes through which they release gas and dust when heated by the Sun, and the behaviour of that material after it leaves the nucleus, tells us a great deal about the environment surrounding each comet.
The dust grains that are released from comets follow orbits around the Sun that are affected by the solar radiation: photons striking these tiny grains push them away in the direction opposite to the pull of the Sun’s gravitational field, creating a dust tail. For very small grains, this radiation force can be strong enough to overcome gravity and can blow them out of the solar system! The gases that are released get ionized, and join the flow of the solar wind. These dynamic, glowing ion tails tell us about the changing activity levels of the comet and the variations in the solar wind itself.
Recent work in our group has revealed strong evidence of solar wind effects on dust tails too (e.g. Price+ 2019): extensive dust tails have been found to be moulded and re-arranged by the effects of the fast flow of charged material from the Sun, through processes that we don’t fully understand. This PhD project would build upon this tantalizing work, through the analysis of imaging data obtained by professional and amateur astronomers on Earth, by space-based imagers that are primarily designed to study the Sun and its near-environment, and with newly-gathered images. As well as helping us better understand the expected influence of sunlight and the solar wind on the comets’ dust and ion tails, the research would involve searching for further evidence for the solar wind’s effects on dust tails, and applying our understanding of structures in the solar wind through instruments such as those on the Solar Orbiter spacecraft, to try to determine the processes responsible for rearranging dust tail material in particular. The outcome of this research is expected to benefit preparations for ESA’s Comet Interceptor mission, due for launch in 2029.
Ramanjooloo & Jones, JGR, 2022
Price, O., et al., Icarus 319, 540, 2019, 2022

Desired Knowledge and Skills

Undergraduate in astrophysics, planetary science, or a related field.
Strong computational skills would be a benefit.

Solar Physics

Our Sun, the Astrophysical Particle Accelerator

Supervisor: Dr. Hamish Reid

Our Sun’s outer atmosphere is extremely unstable. Frequent explosions occur in the atmosphere of the Sun with enough energy to power the Earth for 100,000 years. Particle beams are accelerated to near-light speeds, plasma is super-heated to beyond 10 million Kelvin, and periodically huge volumes of mass, known as solar storms, are ejected. Most astrophysical particle acceleration is astronomically far away which makes data scarce, but our close proximity to our Sun makes it a local laboratory that provides a bounty of data. Understanding the acceleration and transport of particle beams is an important, modern challenge. Moreover, the effect of our active Sun on the Earth (known as space weather) can have a direct economic impact though damaging satellites, disrupting radio communications and destabilised power grids through increased electric currents. Depending on interest, there are two research avenues that can be perused to understand these solar explosions.
Using an observational approach, we will analyse the near-relativistic electron beams that are accelerated by solar explosions using the radio emission they produce. Known as solar radio noise storms, these acceleration events are believed to be caused by complex magnetic fields becoming unstable and energising the local particles, a process that is ubiquitous across all astrophysical particle acceleration. During this project, we will statistically analyse the periodicity of these noise storms, their amplitude variation and how the radio emission evolves in frequency to quantify the properties of this energy release and compare them with particle acceleration models. We will also compare the positions of these noise storms with the magnetic features in the atmosphere of the Sun, and plasma diagnostics, using the Extreme Ultraviolet Imager on-board ESA’s Solar Orbiter (launched 2020). The project has significant scope for highly novel research as radio noise storms has been underused historically due to poor radio telescope resolutions. This problem has recently been remedied by using new-age radio interferometers like the Low Frequency Array (LOFAR) with orders of magnitude better resolution that before.
Using a numerical approach, we can simulate the propagation of these near-relativistic electron beams by using a high-performance, parallelised code. By estimating the initial conditions of the electron beams from solar observations, we can model how these beams propagate out from the atmosphere of the Sun, and how they interact with the solar atmosphere to produce plasma waves that result in the radio emission we detect. We will analyse the effect of multiple beams being accelerated in close succession and compare our results with radio observations to refine the theory of both particle acceleration and transport. There is scope to build upon and refine the simulation code by adding additional physical terms to more completely replicate the real physical environment of the Sun. We can also extend our simulations out to distances close to the Earth so that we can use direct plasma measurements by spacecraft to bound our results. Depending on individual student interest, we can then directly analyse the particle beams using NASA’s Parker Solar Probe (launched 2018) and ESA’s Solar Orbiter (launched 2020), spacecraft that are flying close to the Sun than ever before.

Desired Knowledge and Skills

Undergraduate in astrophysics
Strong computational skills
Experience in data analysis

Space Plasma Physics

Investigating the Earth’s magnetosphere using multi-spacecraft measurements

Supervisor: Prof. Andrew Fazakerley

The Earth’s magnetosphere is a large dynamic structure whose behaviour remains only partially understood despite study over several decades. In the last decade an unprecedented and growing number of space plasma physics research missions has been collecting data in the magnetosphere, including Cluster, THEMIS, VAP, SWARM and MMS, each a multi-spacecraft mission in its own right. Careful planning has gradually brought the orbits of Cluster, MMS and THEMIS in particular into well coordinated alignments, so that the grand constellation has been able to make simultaneous measurements at key locations across the magnetotail in summer seasons, at the bowshock, magnetosheath and magnetopause in winter seasons and along the magnetopause flanks in spring and autumn seasons. Similarly, in all seasons these many spacecraft have regularly collected data throughout the inner magnetosphere.
These newly collected data have as yet received limited attention, but the science operations that produced the data were designed to allow investigations of diverse unresolved or only partially resolved questions such as the nature of the process by which the cold, dense plasmasheet is formed, the nature and origin of north/south asymmetries on the magnetotail and of the cusps, the distribution and scale of reconnection sites through the magnetotail plasmasheet and across the magnetopause, the sequence of events in the magnetotail corresponding to auroral substorms, the fate of plasma populations injected into the inner magnetosphere during substorms and their possible contribution to radiation belt population enhancement and loss, and the physical processes at work in the auroral acceleration regions. The supervisor team has prior experience in all these areas.
The aim of the project will be to explore the datasets produced in the planned observations seasons associated with one or more of these science goals, and to identify and analyse data from particularly interesting multi-mission, multi-spacecraft conjunctions, in order to shed new light on these long-standing questions. Magnetotail or magnetopause projects would likely be the most productive areas for initial study.

Desired Knowledge and Skills

Undergraduate in physics or astrophysics
Good understanding of classical electromagnetism (Lorentz force, Maxwell’s equations, etc.)
Knowledge of plasma physics is desirable but not required

Solar Orbiter: Studies of the Origins and Dynamics of the Solar Wind Charged Particle Populations

Supervisor: Prof. Christopher Owen

UCL/MSSL is the Principal Investigator (PI) Institute on an international consortium providing the Solar Wind Analyser suite (SWA) of instruments for the ESA Solar Orbiter mission. Using 3 scientific sensors, SWA is able to sample electron, proton, alpha particle and heavy ion populations at various distances down to 0.28 AU from the Sun (i.e. around a quarter the distance from the Sun to the Earth) and at high solar latitudes. In particular, UCL/MSSL has designed and built the Electron Analyser System (EAS) for the SWA suite. SWA partners in France, Italy and the USA have provided the Heavy Ion Sensor (HIS) and Proton-Alpha Sensor (PAS) for the suite. In addition, MSSL has a major role in the EUI instrument on the spacecraft, which consists of a suite of imaging telescopes to observe the solar atmosphere. EUI will allow us to determine the global structure of the solar corona and to provide a crucial understanding of fine scale processes in the dynamic solar atmosphere. Images taken by EUI offer an indispensable link between the solar surface and the outer corona, which ultimately shapes the characteristics of the interplanetary medium sampled in situ by SWA and other instruments on Solar Orbiter.

The mission was launched on 11^th Feb 2020, and started its nominal mission at the end of 2021. The first coordinated campaign between all instruments on Solar Orbiter was run during the perihelion passage in March 2022, when the spacecraft reached a distance of 0.3 AU from the Sun. Similar observations over ~10 day windows are being planned and executed for each subsequent perihelia, which occur every 6 months at least until the end of the extended mission phase in 2031. Although EUI and other remote sensing instruments nominally only take the highest resolution observations during these windows, SWA and other in situ instruments continuously take data throughout an orbit. Thus we already have available, and will continue to build, an important new data set that is ripe to support analysis within a PhD program starting in September 2023. In particular, we would aim to use measurements from the 3 SWA sensors to undertake studies of the nature of the solar wind particle populations, their variability, and plasma processes such as magnetic reconnection, collisionless shocks, turbulence, instabilities and dynamics occurring within the solar wind between 0.28 and 1 AU . However, it is also possible to plan a PhD project which would make use the MSSL involvement in both SWA and EUI to support studies of the Sun-solar wind connections, which represent the headline goals of the mission. In addition, it would be beneficial to undertake coordinated studies with data from other missions, such as NASA’s Parker Solar Probe.
Many potential projects fall within the scope of the mission science plan (interested students may wish to consult the draft ‘Science Activity Plan’ https://issues.cosmos.esa.int/solarorbiterwiki/display/SOSP/SAP-related+work generated by the PI’s and ESA) and so a potential tailoring to the specific background and interests of a research student are possible. For example, the solar wind electron population in general consists of 3 components which together contain information about the processes occurring at the source region on the Sun, the magnetic connections of the sampled plasma back to the Sun and on the plasma processes (e.g. turbulence, wave-particle interactions and magnetic reconnection) which may be occurring within the solar wind itself. Separating the effects of these processes is a complicated task requiring high-cadence, high resolution data of the type that will be available from SWA EAS. As a specific example of the kind of Sun-solar wind connections science envisioned here, a student might undertake studies of both the global drivers and local properties of fast and slow solar wind and their relationship to solar activity. Such activity is a prime target for EUI, while understanding the relationship to the composition of the source regions is a key task for the SWA heavy ion sensor. Thus linking the properties and nature of particular solar wind streams to the properties of the various drivers is illustrative of a number of potential studies that could be done with the combined Solar Orbiter observations.
The results of such projects are critical to the success of the overall ESA Solar Orbiter program, and the student will thus also be an integral part of the MSSL science and science-planning teams. There will also be opportunity to collaborate with our partners in Europe and the USA, who have provided the HIS and PAS sensors for the SWA suite and other major subsystems for EUI. This project will place the student in a good position to collaborate more generally and to find future positions e.g. within the Solar Orbiter community internationally.

Desired Knowledge and Skills

Undergraduate degree in physics or closely related topic.
Strong computational skills.
Strong interest in data analysis.

Determining the geomagnetic and heliophysical parameters that control increases and decreases in Earth’s outer radiation belt

Supervisor: Dr. Colin Forsyth

Earth’s geospace environment incorporates a dynamic population of near-relativistic electrons trapped on magnetic field lines that extend out to geosynchronous orbit known as the Outer Radiation Belt (ORB). These electrons can damage spacecraft components and even cause terminal spacecraft failures thus forecasting and nowcasting the conditions in the ORB are critical to spacecraft operations.
The number of energetic electrons in the ORB determined from a combination of acceleration and loss processes. Electromagnetic waves can cause electrons to diffuse inwards across magnetic field-lines, causing the electrons to gain energy. At the same time, other electromagnetic wave populations can scatter the electrons into the atmospheric loss cone, causing the particles to precipitate into the upper atmosphere.
Current physics-based models of the radiation belts require global, statistical maps of electromagnetic waves to drive the dynamics of the ORB. However, these maps are commonly parameterised by geomagnetic indices which can take the same values during periods of net electron loss or acceleration within the ORB, such as during the main and recovery phases of storms respectively. As such, the models can be using the same wave populations to attempt to model different net changes in the ORB. This leads to two fundamental questions: “what are the electromagnetic wave populations during different net changes in the ORB and what dictates these changes?” and “are the wave populations or gradients in the particle populations the dominant factor in radiation belt dynamics?”.
Observations of the total number of energetic electrons in the radiation belt from the NASA Van Allen Probes mission hint that the changes in the radiation belt can be categorised as either rapid loss, rapid acceleration, or steady loss. Using a combination of in-situ and ground-based measurements, we will challenge the common parameterisation of the wave populations by re-casting the wave and particle distributions in terms of whether the ORB is undergoing rapid loss, steady loss or acceleration and revealing statistically significant differences between them. We will also examine whether categorising the waves in the same wave can improve physical models of the radiation belts.
This project will involve the examination of a variety of data sources including in-situ observations from missions such as Van Allen Probes, Arase and SAMPEX as well as ground-based data from magnetometer chains. Existing publicly available models will be adapted to examine the impact of the new results.

Desired Knowledge and Skills

Undergraduate degree in Physics, with a strong interest in solar or space plasma physics.
Strong computational skills in a relevant programming language (IDL, Matlab, Python).
Good statistical and mathematical skills.

Other PhD opportunities in UCL

There are similar PhD projects available in other departments in the UCL, which are sometimese (co-)supervised by our academic staff. Such opportunities are listed below. Please note that you need to submit an application to the other department or Centre for Doctoral Training, if you are also applying for their projects.