Seminar Series

Linking accretion physics from protostars to supermassive black holes

Speaker

Simone Scaringi

Institute

Lecturer in Astronomy in the School of Physical and Chemical Sciences, University of Canterbury

Time & Place

Fri, 04 May 2018 11:00:00 NZST in West Room 531

All are welcome

Abstract

From planets to super-massive black holes, accretion (the accumulation of matter on a self-gravitating body through gravity) is the process by which most objects in the Universe grow in mass. Accretion requires angular momentum to be lost from the in-falling material, usually resulting in the formation of a so-called accretion disk. Although the importance of accretion disks have been recognised for many years, the detailed physics and dynamics are still poorly understood. Over the last decade we have been able to link the accretion physics of stellar-mass black holes with those of super-massive black holes, with over nine orders of magnitude difference in mass. However, we are not yet certain that accretion physics can be extended to include other systems, such as accreting white dwarfs, neutron stars, and young-stellar objects. Although seemingly different observationally, I will show how all these different types of accreting systems have revealed strikingly similar properties. Being just the "tip of the iceberg", the discoveries I will present suggest that a single unifying physical model exists to explain how accretion disks behave throughout the Universe, irrespective of the mass, size, or type of the accreting object.

Biography

Simo lectures Astronomy in the School of Physical and Chemical Sciences at the University of Canterbury. Before moving to New Zealand he held a Humboldt Fellowship at the Max-Planck-Institute for Extraterrestrial Physics, a FWO Pegasus Marie Curie Fellow in the Institute of Astronomy at KU Leuven, and before that he was a postdoctoral researcher in the Department of Astrophysics at Radboud University Nijmegen. He completed his BSc in Maths with Astronomy, and obtained his MPhil and PhD in the Astronomy Group at the University of Southampton.

Simo’s current research is focused on testing whether accretion physics is universal across different types of accreting systems on all mass and size scales. He mostly study observations of accreting compact objects (with black hole, neutron star or white dwarf accretors), supermassive black holes at the centre of Active Galactic Nuclei, and young-stellar objects. He is also very interested in machine learning applied to astronomical datasets, and is currently focused on Deep Learning and Convolutional Neural Networks. He is thus mostly an observational astronomer, but occasionally attempt some theoretical modelling.

Simo also runs The Interacting Binary Newsletter, a monthly electronic publication dedicated to the observation and theory of interacting binaries of all sorts.