GBT19A-429

An Important Mass Measurement of a Nearby Pan-Spectrum Millisecond Pulsar

Abstract

The millisecond pulsar (MSP) J1231-1411 is one of four vital targets for the Neutron Star Interior Composition ExploreR (NICER) mission, which aims to probe the composition of neutron stars using mass measurements from X-ray MSP timing. In a highly inclined system, the mass of an MSP and its companion can be measured through the detection of a relativistic effect called Shapiro delay. Combining these mass limits with MSP radius measurements from X-ray light curves can put significant constraints on the neutron star equation of state. A joint analysis of Fermi Gamma-ray and Nancay Radio data suggests that J1231-1411 is in a highly inclined system; however, if we wish to precisely measure Shapiro delay, a campaign on a high-gain radio telescope like the GBT is absolutely vital. We propose to use up to 22 hours on the GBT to glean a pulsar mass from Shapiro-induced delays. In combination with NICER radius measurements, this campaign could help put significant constraints on the neutron star equation of state.

Investigators

Name	Institution
Thankful Cromartie *	Cornell University; Virginia, University of; Naval Research Laboratory
Scott Ransom	National Radio Astronomy Observatory; Virginia, University of
Paul Ray	Naval Research Laboratory
Sebastien Guillot	Centre National de la Recherche Scientifique
Lucas Guillemot	University of Orleans
Ismael Cognard	Paris, Observatoire de
Jonathan Colen	Naval Research Laboratory
Zaven Arzoumanian	Goddard Space Flight Center
Matthew Kerr	Naval Research Laboratory

* indicates the PI