School of Physics and Astronomy

AU researcher wins grant to map the cosmos with MeerKAT radio telescope

Dr. Alkistis Pourtsidou, a lecturer in the Astronomy Unit, has been awarded a grant to study the large-scale structure of the Universe using a new radio telescope in South Africa.

7 November 2018

news image

The MeerKAT radio telescope, currently finishing construction in the Karoo desert in South Africa. Courtesy: SKA SA.

A lecturer in the Astronomy Unit, Dr. Alkistis Portsidou, has been awarded a grant to study the large-scale structure of the Universe using a new radio telescope in South Africa.

The funding, to the tune of £258k, was awarded through the highly-competitive Consolidated Grant scheme of the UK government's Science and Technology Facilities Council (STFC). Dr. Pourtsidou's project, "Neutral Hydrogen intensity mapping with MeerKAT", will develop new analysis methods to measure the extremely faint radio signal from the neutral hydrogen that pervades the Universe. The ubiquity of neutral hydrogen makes it an excellent tracer of the overall distribution of matter in the cosmos - most of which is in the form of invisible 'dark matter' which cannot be seen directly by telescopes.

The study will be carried out with the new MeerKAT radio telescope, currently finalising its construction in the Karoo desert region of South Africa. The telescope is made up of an array of 64 dishes, each 13.5 metres in diameter, that can be used to map the neutral hydrogen signal over a large are on the sky. A key challenge is calibrating the individual telescopes extremely precisely, so that the maps they construct give a true representation of the distribution of matter in the Universe. This is made all the more difficult by the bright radio emission from our own galaxy, the Milky Way, which swamps the neutral hydrogen signal, and so must be removed very carefully.

Dr. Pourtsidou's project will develop the tools to tackle these important issues, making it possible to make one of the largest maps of the Universe ever with MeerKAT over the next few years, and ultimately laying the groundwork for a much larger mapping project with MeerKAT's successor, the Square Kilometre Array.