The Astronomical Society of Glasgow's next public lecture for the 2018 - 2019 session will be Thursday 21st March, whenProf Nial Tanvir, Lecturer in Physics and Astronomy, Department of Physics and Astronomy, University of Leicester, will be presenting What Re-Ionised the Universe?

The lecture programme will start promptly at 7:30pm, and will be preceded by a presentation from the ASG's Observing Section, beginning at 6:45pm.

Please be aware there is a room change for this lecture. It will take place in room 6.67, rather than the usual 6.41. Details of how to find this room can be found at the end of this article.

Schematic timeline of the universe, depicting reionisation's place in cosmic history.
Image: NASA [Public domain], via Wikimedia Commons
 

At some point during the first few hundred million years after the Big Bang, the tenuous gas that makes up the majority of the normal baryonic matter in the universe, went from being completely neutral to being almost completely ionized. This requires a lot of high energy radiation, the source of which has yet to be identified. It has long been thought that the most likely candidate is ultra-violet radiation emitted from the first generations of massive stars, but questions remain: were there enough stars? did they produce enough radiation? and did that radiation escape from their host galaxies to do the reionization? 

 

Gamma-ray bursts are the brightest and most violent explosions we know of. Thus they can be seen to very great distances and used to probe the conditions in the early universe, in particular the amount of stellar UV radiation leaking out into intergalactic space. Recent results from GRB studies suggest big problems for the hypothesis that star-light drove the reionization process, potentially leaving the stage open for more exotic explanations.

 

Nial obtained his BSc and PhD degrees at the University of Durham. He held post-doctoral positions in Durham and at the Institute of Astronomy in Cambridge. In 1999 he was appointed as a lecturer at the University of Hertfordshire, and in 2006 moved to Leicester as Professor of Astronomy. His research interests have spanned the extragalactic distance scale, galactic structure and evolution, and the study of exotic exploding stars, in particular gamma-ray bursts. In 2002 he was the co-recipient of the European Union Descartes Prize, recognising pioneering contributions to the study of gamma-ray burst afterglows, and was awarded a PPARC Senior Fellowship in 2005. He is also the 2019 Herschel Medalist of the Royal Astronomical Society.

https://www2.le.ac.uk/departments/physics/people/nialtanvir

 

To find Room 6.67, first find your way to the usual room, Room 6.41, Royal College, Strathclyde University.  Access is via the Montrose Street entrance, take the lift to Level 3, exit the lift (turning left) and take the 2nd (furthest away) set of steps, and go through the double glass doors.  Room 6.41 is on your left approximately half way along the corridor. 

From Room 6.41, Room 6.67 can be found using the following map (click on the map for a larger version):

Finding Room 6.67 from Room 6.41