BHI Colloquium


Tuesday, September 24, 2019, 1:30pm to 2:30pm


BHI Meeting Room

Tejaswi Venumadhav (Princeton University)

Title: A new independent analysis of LIGO data: methods and results

Abstract: The Advanced LIGO and VIRGO observatories detected several gravitational-wave events in their first and second observing runs from 2015 to 2017. The detections were only possible due to sophisticated analyses of noisy strain data that were historically conducted within the collaboration. Recently, we developed an entirely independent analysis of LIGO data that improved its reach by rigorously accounting for inherent systematics, and thereby identified seven new binary black-hole mergers within, including the highest spinning event reported to date. In this talk, I will provide a birds-eye view of the process used to make these detections.


Salvatore Vitale (MIT)

Title: Systematic uncertainties in gravitational-wave data analysis

Abstract: In this talk I focus on potential systematic errors that might affect gravitational-wave data analysis at various steps.
First I focus on binary neutron stars, likely the source type for which electromagnetic counterparts will be found most often.
Margalit and Metzger have recently suggested that if LIGO and Virgo were to release low-latency chirp mass information, that information might be used to guide electromagnetic observations. I show that the point estimates for the chirp mass, and even the total mass, produced by low-latency searches for binary neutron stars are affected by negligible biases, in spite of the missing physics in the template bank.
Then I focus on neutron star black hole mergers, a type of sources yet to be detected. While these systems are extremely interesting from an astrophysical point of view, the high mass ratio, potentially large black hole spin, and the potential presence of tidal effects on the neutron star, make them hard to model. Using recent numerical relativity waveforms to simulate neutron star black hole mergers, I report on the performances of existing waveform models.