12:00–1:00 pm Zoom Room
Igor Andreoni, Caltech, "Results from triggered and un-triggered searches for counterparts to neutron star mergers"
Mergers of binary neutron star systems are great multi-messenger sources. These mergers generate gravitational waves (GWs) detectable with ground-based interferometers and can be accompanied by luminous electromagnetic (EM) radiation. The combined detection of GW and EM signals can enable a large amount of science, ranging from cosmology to fundamental physics and astrophysics of energetic phenomena. However, with only one well-studied multi-messenger case, many questions remain. For example, what is the true binary neutron star merger rate? Are the merger ejecta always rich in r-process elements? What are the EM counterparts to neutron star–black hole mergers? The discovery of a population of kilonovae – the optical/infrared counterparts to neutron star mergers – will allow us to address these and more questions. In this seminar, I will present results from observations carried out by the GROWTH collaboration using wide-field instruments such as theDark Energy Camera and the Zwicky Transient Facility, some during LIGO/Virgo O3 and some still on-going. Finally, I will discuss how we have used systematic triggered and un-triggered searches to understand the kilonova luminosity function and constrain the neutron star merger rate.