Mind the gap: What can we learn about stellar astrophysics from gravitational wave detections of binary black holes?

Speaker: Dr. Rob Farmer (Anton Pannekoek Institute for Astronomy, University of Amsterdam)

Title: Mind the gap: What can we learn about stellar astrophysics from gravitational wave detections of binary black holes?

Abstract: With the detection of binary black hole (BH) mergers from LIGO/Virgo we have opened up the field of gravitational wave astronomy and created a new window into the Universe. These discoveries bring new and independent information about how very massive stars end their life, and the final remnants they leave behind. In this talk I will discuss the stellar physics that goes into the formation of the most massive stellar mass black holes and how the detection of most massive merging pair of black holes to date, GW190521, with both BHs being in the “PISN mass gap” challenges this picture. I will show what physics goes into the location of this mass gap, and how robust we believe the estimate of the location of the mass gap is. I will then discuss what GW190521 informs us about the location of the mass gap, and the implications for finding both black holes in the mass gap. Finally, I will also discuss how measuring the location of the mass gap allows us to place constraints on uncertain stellar physics, namely the C12(alpha,gamma)O16 nuclear reaction rate and what GW190521 can tell us about this nuclear reaction rate.

About the speaker: Rob Farmer has a Masters in physics from Warwick University, UK and a PhD in astrophysics from The Open University, UK. He then went on to do a post-doc at Arizona State University and is currently a senior post doc at the University of Amsterdam. His work mainly focuses on understanding the evolution of massive stars as well as their supernovae. He also is a senior developer for the open source MESA stellar evolution code. Currently his work has been focused on understanding the progenitors of the black holes detected by LIGO/Virgo and what their detections mean for the evolution of massive stars.

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Meeting ID: 995 291 7599
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