22.11.2016

Cosimo Inserra (Queen's University, Belfast, UK)

Going bright: superluminous supernovae

STRESZCZENIE Supernovae, stellar explosions showcasing the dramatic final moments of a star’s life. These have a profound influence upon many diverse areas of astrophysics, including chemical enrichment, feedback in galaxy formation, and stellar evolution. The last six years has seen the surprising discovery of new classes of ultra-bright ‘superluminous’ supernovae, some 100 times brighter than classical supernova types, offering new probes of the high redshift universe and the potential for a new class of standard candle. We understand surprisingly little about the physics of these events and yet they represent some of nature's brightest explosions. These supernovae appear to occur exclusively in dwarf, metal-poor host galaxies with typical luminosity of Mg > -17 mag at at redshifts between 0.1 and 4.0, but the cause of their extreme luminosity remains unknown. Theories include magnetar spin down, pair-instability explosions and shell collisions. Here I report the current scenario of these superluminous supernovae, highlighting the different subclasses. I will also focus on the ongoing science projects related to these explosions, their use in the LSST and Euclid era and the open questions that researchers are still facing.

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O PRELEGENCIE I am an observational astronomer, and my primary research interest is in the understanding of supernovae. In particular I work on observations and cosmological use of the brightest supernovae via multi-wavelength analysis of both space- and ground-based observations. After graduating with a first-class honours degree in Physics and Astronomy at the University of Catania in 2008, I started my PhD in January 2009 at the Italian National Institute of Astronomy in collaboration with the University of Catania under the supervision of Dr. Turatto. It was titled "Bright Core-collapse Supernovae", and completed in February 2012. I then took a five years postdoc with Prof. Stephen Smartt at Queen's University Belfast to work on data analysis of the PESSTO collaboration and on peculiar supernovae. I was finalist (top 3) and best STEM postdoc at the Vice-Chanchellor's Postdoctoral Research Prize at Queen's in 2015 with about 500 applicants. From Spring 2017 I will take a two year postdoc with Prof. Mark Sullivan at the University of Southampton.