Seminar Series

Checking for duplicity (of stars) in the Universe

Speaker

Dr JJ Eldridge, Senior Lecturer

Institute

Physics Department, Faculty of Science, University of Auckland

Time & Place

Fri, 18 May 2018 11:00:00 NZST in West 531

All are welcome

Abstract

It is becoming widely accepted that most stars are in binary or multiple star systems with a significant fraction having their evolution affected by binary interactions. Most studies of stellar populations still ignore this and the impacts the binary interactions can have on the appearance and nature of stellar populations. The BPASS (Binary Population and Spectral Synthesis; bpass.auckland.ac.nz) code has been attempting to make it easier to take account of interacting binaries with results and models being made publicly accessible and by making as broad predictions as possible (Eldridge et al., 2017).

I will first describe the BPASS project and recent results on modelling HII regions and on studying the old stellar populations in globular clusters with our latest v2.2 models I will then present our recent attempts at supernova lightcurve population synthesis. As all the BPASS stellar models are calculated in a detailed stellar evolution code we can use the final progenitor structure in the SuperNova Explosion Code (SNEC) to predict the full range and diversity of supernovae expected from a stellar population including all the progenitors affected by binary interactions. We will show we can how we reproduce the broad range of expected SN types but also the rare supernovae that don't match into those expected types that have not yet been observed.

Biography

JJ obtained their MA and MSci degrees from the University of Cambridge in 2001. They then stayed at the University to study for my PhD in astrophysics at the Institute of Astronomy. After this JJ undertook postdoctoral research at the Institut d’Astrophysics de Paris, Queen’s University Belfast and the Institute of Astronomy. In 2011 JJ was appointed as a Lecturer of Astrophysics at The University of Auckland.

JJ’s research covers all aspects of stellar structure and evolution. The aspects they concentrate on include massive stars, interacting binaries, supernovae and gravitational wave sources. In addition to their research activities JJ is a keen science-fiction consumer and has given talks on the topic of assessing how accurate science-fiction can be with titles such as: "The Science of Sci-Fi: The Good the Bad and the Ugly" and "The Science of Sci-Fi: does every planet look just like home?"