GBT21B-205

Timing and General Relativity in the Double Pulsar System

Abstract

We propose to continue our regular and campaign-style observations of the double pulsar J0737-3039A/B, with 101 hours of observing time in 2021/2. This system of two pulsars provides a truly unique laboratory. Our previous observations have enabled unique high precision tests of general relativity, also detecting new effects. These include retardation and aberrational light-bending that allow determination of the spin direction of the pulsar. In total, we have precision measurements of 5 post-Keplerian parameters and detection of a 6th, more information than for any other known binary pulsar. For some of these effects, the measurement precision is now so high that for the first time we have to take higher-order contributions into account. These include the contribution of the A pulsar's mass loss (due to spin-down processes) to the observed orbital period decay, a relativistic deformation of the orbit, and the effects of the equation of state of super-dense matter on the observed post-Keplerian parameters via relativistic spin-orbit coupling. Continued observations with the GBT will lead to further unprecedented tests of general relativity and alternative theories of gravity.

Investigators

Name	Institution
Victoria Blackmon	West Virginia University
Michael Kramer *	Manchester, University of; Max-Planck-Institut für Radioastronomie
Ingrid Stairs	British Columbia, University of
Maura McLaughlin	West Virginia University
Robert Ferdman	McGill University; East Anglia, University of
Andrea Possenti	Istituto Nazionale di Astrofisica
Paulo Freire	Max-Planck-Institut für Radioastronomie
Nihan Pol	Oregon State University; Wisconsin at Milwaukee, University of; Texas Tech University
Dick Manchester	Australia Telescope National Facility
Andrew Lyne	Manchester, University of
Marta Burgay	Istituto Nazionale di Astrofisica

* indicates the PI