Colloquium Abstract - Cromartie - 2026Jan23

January 23, 2026

11:00am Mountain

Thankful Cromartie (NRL)

 

Constraining the Dense Matter Equation of State with Next-Generation Pulsar Timing Arrays

 

Abstract

Radio-frequency observations of millisecond pulsars play a key role in determining the equation of state (EoS) of supranuclear-density matter in neutron star interiors. High-precision timing of massive pulsars—especially those with well-measured post-Keplerian effects such as the relativistic Shapiro delay—provides direct constraints on the EoS, as valid models must explain the existence of neutron stars with masses greater than ~2 solar masses. Pulsar timing array (PTA) experiments, such as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), provide unique opportunities to conduct these mass measurements for a growing and diverse sample of pulsar binaries. In this talk, I will present a recent mass constraint for PSR J1231-1411 obtained with the Green Bank and Nançay radio telescopes, highlighting the benefit of long-term radio timing campaigns for even poorly-determined neutron star masses. I will then discuss the new era for which PTA collaborations are preparing. Next-generation radio facilities and new pulsar timing techniques will not only help elucidate the origin of the nHz gravitational background, but will also allow for unprecedented precision in neutron star mass measurements to support further constraints on the dense matter EoS.


Local Host: Paul Demorest

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