Academic projects search

This project is to develop models of resolved star formation on galactic scales. This will involve modelling a full galactic potential and how it drives the formation of molecular clouds and the onset of gravitational collapse and star formation. feedback from ionisation and supernova will be included to assess molecular cloud lifetimes and star formation efficiencies.

Extensive layers of diffuse ionized gas are observed in the Milky Way and other galaxies. This project will study the structure, ionization, heating, and dynamics of diffuse ionized gas using our newly developed radiation hydrodynamics codes that incorporate feedback processes including photoionisation, stellar outflows, and supernovae. Output from our 3D rad-hydro simulations will be compared with emission line observations of the diffuse ionised gas.

This project will use (and futher develop) our new radiation hydrodynamics codes to syudy the effects of stellar feedback on the structure, dynamics, and star formation rates in star forming regions (parsec sizescales) and the interstellar medium (kiloparsec sizescales). Feedback processes that are readily incorporated into our codes include photoionisation, radiation pressure, dust heating, stellar outflows, and supernovae. In addition to studying these processes in star forming regions, the new numerical codes are also applicble to numerical studies of galactic outflows and the impact of feedback processes and leakage of ionising radiation into the intergalactic medium.

Our knowledge of exoplanet atmospheres is undergoing a paradigm change following the launch of the James Webb Space Telescope (JWST). High-quality spectroscopic observations of exoplanet atmospheres necessitate a careful reassessment of model assumptions that were sufficient in the pre-JWST era, in order to ensure the reliable inference of atmospheric properties (e.g. the chemical composition, temperature profile, and aerosol properties).
In this MSc (res) project, you will investigate new ways to improve state-of-the-art models of exoplanet spectra. You will also have the opportunity to apply these models to JWST observations of giant exoplanets, which will allow you to measure the atmospheric properties of worlds around other stars.

• The Centre for Exoplanet Science

Many gravitational microlensing events involve binary (or multiple) systems, which can be any combination of stars, stellar remnants, brown dwarfs, and planets. Yet, there is quite a lack of systematic studies on what microlensing observations can tell us about the demographics of such systems. This now becomes an even more promising topic as not only photometric but also astrometric microlensing signatures are observed.

This project can take different directions in line with the main interests of the student, where specific questions could include a) the overlapping mass regime between planets and brown dwarfs, b) close binaries, or c) the yet unresolved question why so few binary-source events have been identified (with potential implications on the derivation of planet population statistics).

This project would be eligible for funding including: STFC DTP scholarships administered by the University. (Must be within STFC remit.)

Most stars form in clusters, where energetic feedback from massive (proto)stars – including outflows, ionization, heating, and winds – shapes the environment and impacts accretion. The relative importance of different feedback processes is a key outstanding issue in our understanding of massive star formation.

The aim of this project is to conduct a large-scale observational study of the role and physics of feedback in young massive (proto)clusters, using ALMA and Jansky Very Large Array (VLA) observations of "Extended Green Objects (EGOs)". The PhD project will focus on imaging and analyzing ALMA observations of the EGO-10, a sample of typical young, massive star-forming regions that exist in a specific evolutionary state where active outflows dominate their infrared appearance.

This project would be eligible for funding including: STFC DTP (Must be within STFC remit.)

Determining the demographics of cool planets by means of microlensing is one of the key science goals of NASA's Nancy Grace Roman Space Telescope mission. Already the much smaller data rate of the most advanced ground-based surveys poses a key challenge for the modelling of the detected gravitational microlensing events. The major bottleneck to be overcome is the reliance on human judgement in the data analysis process. Any scalable solution not only needs to be fully-automated ("data-in-model-out"), but also needs to take into account the specific statistics of time-series observations, with their correlated noise and non-Gaussian distribution of measurements. This results in a complex Bayesian interference problem involving an intricate high-dimensional parameter space.

This project would be eligible for funding including: STFC DTP scholarships administered by the University. (Must be within STFC remit.)

Two fundamental unanswered questions in star formation are: (1) how, precisely, do high-mass stars (M>8 M_sun) acquire their mass? and (2) what produces the very high multiplicity fraction of high-mass (O and B type) main-sequence stars?  Some recent models suggest that the answers to both questions may be linked to the structure and (in)stability of accretion discs around high-mass protostars, which are less well-understood than their low-mass counterparts.  This PhD project will focus on the imaging and analysis of high-resolution ALMA observations of a small sample of discs around high-mass protostars, to study disc structure and stability, search for signatures predicted by models of "bursty" or episodic accretion and constrain the level of multiplicity present in the early stages of high-mass star formation. 

This project would be eligible for funding including: STFC DTP (Must be within STFC remit.) 

Stars interact with their orbiting exoplanets in several ways. Tidal interactions can change the orbital dynamics of exoplanets, and the UV and X-ray irradiation from the star can erode the outer atmosphere of the exoplanet, especially when it is young. Stars also interact with their exoplanets through the outflows from their outer atmospheres (or coronae). These outflows can be seeded with clumps of cool, mainly neutral gas that have condensed out of the million-degree plasma of the star's corona. Recent observations of the lowest-mass stars have also revealed the signatures of what appears to be dust entrained in these clumps. Its origin is unclear, but one hypothesis is that it has been torn from the atmospheres of close-in, rocky exoplanets. Its presence may therefore reveal the rate at which exoplanet atmospheres can be stripped by their parent stars.
This project will investigate these clumps, using data-driven modelling of the composition and dynamics of these clumpy outflows.

• The Centre for Exoplanet Science

The circumgalactic medium (CGM) that surrounds galaxies provides the fuel for them to grow, and the sink for them to stop growing. Quantifying and understanding the CGM is crucial for linking galaxy growth over cosmic time to the large web-like structures (Cosmic Web) in which they live, and thereby understanding how and why some galaxies continue to grow while others stop forming stars.  Cross-correlation between absorption systems detected in the spectra of background quasars with a foreground galaxy population have revealed important details about the CGM of galaxies. In this project, we will apply this method to unprecedentedly large samples of galaxies and background QSOs from the DESI survey (https://www.desi.lbl.gov). We will study the gas profiles around galaxies with different star formation histories, living in different environments, and in the filaments that feed them. This work will be supported by parallel analyses in simulations.

This project would be eligible for funding including: STFC DTP (Must be within STFC remit.)