VIRTUAL

 

Thursday, August 5th    2021

3:45 – 4:45 p.m.

WEBEX

  

Speaker:  Dr. Jocelyn Read

 

 

Assistant Professor of Physics

California State University, Fullerton

 

 

 

“Gravitational-wave observations of neutron-star mergers”

 

 

 

Abstract: 

New discoveries by LIGO, Virgo and KAGRA are beginning to inform our understanding of dense matter and stellar evolution.  The neutron-star/black-hole mergers GW200105 and GW20011 and the heavy neutron-star merger GW190425 have revealed that the gravitational-wave population includes binary systems unlike those previously observed in our Galaxy. We have also used the gravitational-wave data of GW170817 - the first signal from merging neutron stars - to constrain the equation of state of dense matter in neutron stars. With more distant sources typically expected, the distribution of masses in compact binary mergers will become a key observable in the coming years of gravitational-wave astronomy. In this talk, I will discuss methods being used to explore matter and mass properties for LIGO/Virgo neutron stars. I will discuss how these results fit with other neutron-star observations, outline prospects of learning about matter in the current Advanced-detector era, and extrapolate to the potential of next-generation gravitational-wave observatories like Cosmic Explorer to map the phase diagram of dense neutron-rich matter and the endpoints of stellar evolution. 

 

Bio:

I study neutron star astrophysics and gravitational waves. Neutron stars are the collapsed remnants of massive stars, the most compact astrophysical objects outside of black holes, and the place where matter makes it's last stand against the overwhelming force of gravity. Inside a neutron star, matter is compressed into strange new forms, pushing the limits of our understanding of condensed matter and particle interactions.  Like many stars, neutron stars can be found in binary systems, where pairs of neutron stars orbit. As they do so, they lose energy to gravitational waves, eventually spiralling towards each other and colliding. This will release huge amounts of energy in gravitational-wave signals that LIGO, the Laser Interferometer Gravitational-wave Observatory, hopes to observe. These collisions may also explain some of the Gamma Ray Bursts seen by space telescopes like NASA's Fermi. My group and I work to understand and model how neutron stars interact, collide, and radiate energy, so that observations can tell us new things about their structure and composition.