Institute for Astronomy
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Active Galactic Nuclei PhD Projects

Research projects on offer in our Active Galactic Nuclei group.

Quasar variability over a broad range of timescales

Dr James Aird and Prof Andy Lawrence

A defining feature of quasars - associated with rapidly accreting supermassive black holes - is the substantial variability of their emission at different wavelengths over timescales spanning from hours to many years. Such variability must arise from the material close to and falling into the black hole, providing unique insights into the environments of black holes, but the physical mechanisms responsible for the variability remain unclear. This PhD project will take advantage of new data from the Vera Rubin Observatory's Legacy Survey of Space and Time (LSST) that will scan around half the sky every 3 days over the next 10 years at optical wavelengths. We will combine these new high-cadence data with existing samples of hundreds of thousands of quasars with optical imaging that spans the last 7 decades. Using sophisticated statistical approaches, we will quantify the ensemble variability properties of these quasars from these long timescales down to the rapid variations revealed by LSST, explore physical models of their origin, and investigate correlations with fundamental properties of the black holes such as their masses or accretion rates. As the project develops, we will look to extend these analyses to quantify the black hole population and its evolution with time, as well as comparing to multi-wavelength tracers to gain further insights into the nature of quasar variability.

Under the Computational Astrophysics projects, see also:

Under the Galaxy Formation & Evolution projects, see also:

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