Dr Julie Wardlow

Research Fellow and Lecturer

PhD Supervision Interests

Exploring Lyman-alpha emitters in the far-infrared with ALMA Narrowband and 3D spectroscopic surveys have identified thousands of Lyman-alpha emitting galaxies (LAEs) in the distant, early Universe. Lyman-alpha, emitted at rest-frame 1216A, is the strongest emission-line resulting from ionising photons from either young massive stars or super-massive black holes, allowing LAEs to be detected at the furthest cosmological distances. However, interpreting their Lyman-alpha emission is challenging since it can originate from neutral Hydrogen in the inter-, circum- and intergalactic medium, and Lyman-alpha photons can also be self-absorpbed and are easily attenuated by dust. LAEs are typically primeval galaxies that are blue and with young, highly ionising stellar populations and some host active super-massive black holes. Analyses to date suggest that they are dust poor, but there have been few direct observational studies of dust in LAEs because the necessary far-infrared data haven’t been available. Now, with the commissioning of the Atacama Large (sub)Millimeter Array (ALMA) far-infrared observations of large samples of LAEs are available. This project will use ALMA to measure the dust in and around LAEs to understand the impact of dust on our understanding of LAEs and the role of dust and dust-forming processes in the formation and evolution of these primeval galaxies. This project will be jointly supervised by Dr David Sobral and Dr Julie Wardlow; please contact them for further information. Our PhD projects are offered on a competitive basis and are subject to availability of funding. The formation and evolution of the most active star-forming galaxies in the Universe Luminous submillimetre-selected galaxies (SMGs) and dusty star-forming galaxies are distant galaxies that are undergoing immense bursts of star formation, with typical star-formation rates of hundreds to thousands of times that of our Milky Way. These extreme systems provide challenging tests of galaxy formation and evolution theories and they seem to represent a key phase in the formation of the most massive local galaxies. However, despite ~20 years of study, they are still somewhat of a mystery -- even the physical process responsible for triggering the activity in SMGs is still a subject of intense debate. This PhD project will use data from international facilities, including the Atacama Large Millimeter/submillimetre Array (ALMA) and ESO's Very Large Telescope (VLT), to study the physical conditions in submillimetre galaxies. The results will be used to test theories of the formation and evolution of submillimetre galaxies, and probe whether they are caused by galaxy-galaxy mergers as some simulations suggest. Please contact Dr Julie Wardlow for further information. Our PhD projects are offered on a competitive basis and are subject to availability of funding.