Postgraduate research project

Revealing Quasar Host Galaxies with the Vera C. Rubin Observatory

Competition funded View fees and funding
Type of degree
Doctor of Philosophy
Entry requirements
2:1 honours degree
View full entry requirements
Faculty graduate school
Faculty of Engineering and Physical Sciences
Closing date

About the project

The Vera C. Rubin Observatory is a ground-breaking astronomical facility due to start survey operations in 2024-25. The 10-year Legacy Survey of Space Time (LSST) conducted with this new facility will revolutionise astronomy by mapping the entire Southern sky every few days and generating a petabyte scale dataset containing billions of astronomical sources. Within the rich LSST dataset there will be millions of active galactic nuclei powered by accretion onto supermassive black holes. 

In the local Universe supermassive black hole mass is correlated with the stellar bulge mass of the host galaxy but is this also true at high-redshifts? What are the mechanisms by which supermassive black holes and their host galaxies assemble their mass and what role do mergers play in their assembly? It has been challenging to answer these questions because it is difficult to see the starlight within the host galaxies of rapidly growing black holes or quasars due to the glare of the bright quasar, which outshines the host galaxy by several orders of magnitude. LSST's sensitivity to low surface brightness features and image quality makes quasar host galaxies accessible via ground-based imaging. This becomes particularly true in the case of quasars enshrouded by dust as the dust dims the quasar light. Dusty quasars account for a significant fraction of black hole activity in the early Universe and could be a critical phase in the evolution of all massive galaxies. 

The goals of the PhD will be to systematically characterise the multi-wavelength properties of quasar host galaxies as a function of redshift, luminosity and dust obscuration using imaging surveys. You will initially use data from HyperSuprimeCam and VIRCam processed through our in-house image processing pipelines before getting the opportunity to work with the first science images from LSST. 

You will be part of a vibrant and growing research team at Southampton including PhD students and postdoctoral researchers exploiting multi-wavelength data to understand the high-redshift Universe, as well as research software engineers working on image processing pipelines for Rubin LSST and Euclid. As part of the wider team, you will explore synergies between LSST and wide-field spectroscopic surveys like 4MOST and VLT-MOONS as well as space-based imaging from Euclid. The project will give you an opportunity to be part of the international LSST Science Collaborations and to work with scientists in the UK, Europe, USA and Chile. You will confront “big data” challenges and develop a range of transferrable skills related to the analysis of large, complex and multi-variate datasets.