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arXiv · 1404.1458

Realistic Modeling of the Pulse Profile of PSR J0737-3039A

B. B. P. Perera·C. Kim·M. A. McLaughlin·R. D. Ferdman·M. Kramer·I. H. Stairs·P. C. C. Freire·A. Possenti
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Abstract

The Double Pulsar, PSR J$0737$$-$$3039$A/B, is a unique system in which both neutron stars have been detected as radio pulsars. As shown in Ferdman et al., there is no evidence for pulse profile evolution of the A pulsar, and the geometry of the pulsar was fit well with a double-pole circular radio beam model. Assuming a more realistic polar cap model with a vacuum retarded dipole magnetosphere configuration including special relativistic effects, we create synthesized pulse profiles for A given the best-fit geometry from the simple circular beam model. By fitting synthesized pulse profiles to those observed from pulsar A, we constrain the geometry of the radio beam, namely the half-opening angle and the emission altitude, to be $30^\circ$ and $10$ neutron star radii, respectively. Combining the observational constraints of PSR J$0737$$-$$3039$A/B, we are able to construct the full three-dimensional orbital geometry of the Double Pulsar. The relative angle between the spin axes of the two pulsars ($\Delta_S$) is estimated to be ($138^\circ \pm 5^\circ$) at the current epoch and will likely remain constant until tidal interactions become important in $\sim$$85$ Myr, at merger.

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B. B. P. Perera, C. Kim, M. A. McLaughlin, R. D. Ferdman, M. Kramer, I. H. Stairs, P. C. C. Freire, A. Possenti. 2014-04-05. Realistic Modeling of the Pulse Profile of PSR J0737-3039A. https://doi.org/10.1088/0004-637x/787/1/51

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