Department of Physics & Astronomy
University of New Mexico

Center for Astrophysics Research and Technologies Seminar Series

NANOGrav's Search for Gravitational Waves, Including Interstellar Medium Bonus Science

Presented by Tim Dolch (Hillsdale)

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) pulsar timing array collaboration conducts long-term observations of millisecond pulsars with the Green Bank Telescope and other radio observatories. The line-of-sight to each pulsar acts as a detector arm for measuring pulse time-of-arrival perturbations due to gravitational waves (GWs). A common signal has been detected in NANOGrav’s 12.5-year dataset, but the characteristic pairwise correlations predicted from the quadrupolar nature of GWs has yet to be detected. Optical structures associated with radio pulsars can help characterize their lines-of-sight. In particular, bow-shock pulsar wind nebula, such as the Guitar Nebula, can characterize the environments of their associated neutron stars. Additionally, timing observations at frequencies lower than standard timing frequencies (such as with the Long-Wavelength Array) can probe ISM density fluctuations with improved accuracy. Finally, we look at the overall turbulence spectrum of the ISM across the Galaxy, putting together data from pulsar wind nebulae, radio timing observations, and very-local ISM (VLISM) data from both Voyager spacecraft.

2:00 pm, Thursday, November 4, 2021

Disability NoticeIndividuals with disabilities who need an auxiliary aid or service to attend or participate in P&A events should contact the Physics Department (phone: 505-277-2616, email: well in advance to ensure your needs are accomodated. Event handouts can be provided in alternative accessible formats upon request. Please contact the Physics front office if you need written information in an alternative format.

A schedule of talks within the Department of Physics and Astronomy is available on the P&A web site at