Fall 2023 Physics Colloquium: Searching for a Gravitational Wave Background with Pulsar Timing Arrays

Sarah Vigeland, Assistant Professor Center for Gravitation, Cosmology and Astrophysics, University of Wisconsin-Milwaukee

When

3 – 4 p.m., Sept. 8, 2023

Where

Abstract: Pulsar timing arrays use observations of millisecond pulsars to detect nanohertz gravitational waves. The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) Collaboration has recently released their 15-year data set containing observations of 68 millisecond pulsars. These data contain evidence for Hellings-Downs correlations, which are characteristic of a gravitational wave background. In this talk, I will present these results, and discuss the spectral properties of the signal and implications for the astrophysical source. I will also discuss prospects for detecting other types of gravitational wave sources with pulsar timing arrays, including individual supermassive binary black holes.

Bio:

Sarah Vigeland is a gravitational wave astrophysicist whose work focuses on detecting gravitational waves with pulsar timing arrays. She is a member of the NANOGrav Collaboration, and currently serves as chair of the Gravitational Wave Detection Working Group. She earned her Ph.D. from MIT in 2012, and did postdocs at the Jet Propulsion Laboratory and the University of Wisconsin-Milwaukee before joining the faculty at the University of Wisconsin-Milwaukee as an assistant professor in 2019.

In-person only. Refreshments at 2:30 PM, PAS 218

Contacts

Prof. Sam Gralla