Document Type
Article
Publication Date
1-1-2009
Abstract
If a pulsar orbits a supermassive black hole, the timing of pulses that pass close to the hole will show a variety of strong field effects. To compute the intensity and timing of pulses that have passed close to a nonrotating black hole, we introduce here a simple formalism based on two \"universal functions,\" one for the bending of photon trajectories and the other for the photon travel time on these trajectories. We apply this simple formalism to the case of a pulsar in circular orbit that beams its pulses into the orbital plane. In addition to the \"primary\" pulses that reach the receiver by a more-or-less direct path, we find that there are secondary and higher-order pulses. These are usually much dimmer than the primary pulses, but they can be of comparable or even greater intensity if they are emitted when pulsar is on the side of the hole furthest from the receiver. We show that there is a phase relationship of the primary and secondary pulses that is a probe of the strongly curved spacetime geometry. Analogs of these phenomena are expected in more general configurations, in which a pulsar in orbit around a hole emits pulses that are not confined to the orbital plane. © 2009. The American Astronomical Society. All rights reserved.
Recommended Citation
Yan Wang, et. al., (2009) Strong field effects on pulsar arrival times: Circular orbits and equatorial beams.Astrophysical Journal697:1237. DOI: http://doi.org/10.1088/0004-637X/697/1/237
First Page
237
Last Page
246
Publication Title
Astrophysical Journal
DOI
10.1088/0004-637X/697/1/237
Comments
© Astrophysical Journal. Original version available at: http://doi.org/10.1088/0004-637X/697/1/237