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Light Curves of Rapidly Rotating Neutron Stars

Timothy M. Braje·Roger W. Romani·Kevin P. Rauch
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Abstract

We consider the effect of rapid rotation on the light curves of neutron stars with hot polar caps. For $P \approx 3$ms spin periods, the pulse fractions can be as much as an order of magnitude larger than with simple slowly-rotating (Schwarzschild) estimates. Doppler boosting, in particular, leads to characteristic distortion and ``soft lags'' in the pulse profiles, which are easily measurable in light curves with moderate energy resolution. With $\sim 10^5$ photons it should also be possible to isolate the more subtle distortions of light travel time variations and frame dragging. Detailed analysis of high quality millisecond pulsar data from upcoming X-ray missions must include these effects.

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Timothy M. Braje, Roger W. Romani, Kevin P. Rauch. 2000-04-28. Light Curves of Rapidly Rotating Neutron Stars. https://doi.org/10.1086/308448

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