Astrophysics at the University of Exeter

Lead Research Organisation: University of Exeter
Department Name: Physics and Astronomy

Abstract

Our research is focussed on improving our understanding of how stars, disks, and planets form and evolve, and of the physical processes that occur deep in the atmospheres and interiors of stars and exoplanets. We intend to achieve this goal by developing advanced theoretical models and using a combination of state-of-the art computer modelling and observations obtained from cutting-edge facilities.

Stars and planets owe their origins to the gravitational collapse of molecular clouds, resulting in the formation of objects with a wide range of masses. As stars form, they are surrounded by discs of material, which feed the star with mass and are the birthplace of planets. How discs form and evolve, what determines their properties, and how accretion and planet formation proceeds, remain major unsolved questions. Combining different observational methods at various wavelengths and sophisticated computer modelling that include complex physics, we will study in depth all steps, starting from the properties of molecular clouds, that lead to the formation of stars, discs and planets.

After stars and sub-stellar objects form, their further evolution is characterised by complex physical processes, such as turbulent convection and magnetism, that shape their internal structure and their observational properties. Exquisite observational data are now available, with for example asteroseismology providing important constrainsts on the internal structure of stars. We will develop theoretical models and use sophisticated numerical models to improve our understanding of stellar interiors, atmospheres, magnetism, and rotation and to explain various observational puzzles.

We will also develop new observational techniques, carry out new observations, and build new theoretical models for detecting, characterising, and understanding exoplanets. We will also develop original strategies to optimise the detection of small (Earth-sized) exoplanets by understanding and learning how to see through activity "noise" from the host star. We expect to lead the first images and spectra of directly-observable exoplanets using the James Webb Space Telescope. To describe the physical properties of exoplanet atmospheres, we use the Met Office's computer model for the Earth's climate, which has been specially adapted to deal with the different physical process that occur in exoplanet atmospheres. We will also develop new tools to understand the detailed atmospheric chemistry of irradiated exoplanets and which will be optimised to interpret observations.

Planned Impact

We collaborate with a number of partners to apply our research work in a wider context. We are also committed to communicating our results, engaging schools and the general public in an increasing number of ways. Over the period of this grant, we plan to deliver impact with the following beneficiaries:

Climate modelling and exoplanets: Over the past years our adaptations to the UK Met Office software have been deposited back into the shared repository and therefore form part of the base model used for Earth climate and weather prediction. The direct developments required for our scientific objectives have resulted in a more flexible and faster model. Additionally, this work has aided Met Office developments providing flexible idealised algorithms and configurations.

Radiative transfer and skin cancer: Harries, in collaboration with Drs Alison Curnow and Clare Thorn from the University's Medical School is adapting the radiative transfer code TORUS to model light scattering through human tissue. This modification was performed in collaboration with the Centre for Biomedical Modelling and Analysis and it is now being used by a 4-year PhD student to create a 'virtual laboratory' for studying photodynamic therapy. TORUS is also used to model deep Raman scattering in breast tissue (in collaboration with Exeter's biomedical physics group), which is being studied by another PhD student. Deep Raman spectroscopy provides a route to swift, non-invasive diagnosis of breast cancer, and numerical modelling is key to assessing the sensitivity and specificity of the technique.

Exoplanet Explorers: Through partnership with local SMEs, We the Curious & Engine House VFX and with support from our last consolidated grant and the National Space Science Centre, we have produced two innovative, immersive animations, based on our exoplanet research. The first such animation has been viewed over 8 million times, and won both a bronze and People's choice award at the 2018 Lovie Awards. A follow-up animation has recently been completed and released, and was rapidly nominated for a VR award. Our first animation has not only had a significant reach within the general public but also been used in several planetaria including that at the We The Curious Science exhibition centre in Bristol, and enhanced the income of Engine House through the procurement of several new projects. This activity has been partnered by more significant interactions, through the provision of Exoplanet Explorer sessions at schools throughout the southwest, featured on BBC Spotlight (regional news). Mayne has been awarded an STFC Nucleus grant to co--develop a game based on our exoplanet research, which will be incorporated into our wider activities. Our activities during this grant will all provide scientific input into our future development of the exoplanet explorers engagement materials, and ongoing events.

Education, schools, and teachers: The Exeter Astrophysics group members are also extremely active in outreach activities with local schools covering astrophysics more broadly. Regular events include: National Science Week; Big Bang South West!; Institute of Physics Festival of Physics; Stargazing Live!; Pint of Science; Progression in Physics- a long-term project with Year 12 students from widening participation schools who visit the University eight times in the year to experience different aspects of Physics/Astrophysics at university-level; and hosting work experience students. The group have engaged in events at schools throughout the southwest providing presentations, workshops and 'hands-on' sessions, alongside a youtube channel dedicated to explaining our research in short segments. For such cross-cutting activities, all projects, staff and students are generally involved at some level. For this grant we will continue these activities and expand our engagement resources and online content.

Publications

10 25 50