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arXiv · 1910.08608

Detecting Gravitational Scattering of Interstellar Objects Using Pulsar Timing

Ross J. Jennings·James M. Cordes·Shami Chatterjee
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Abstract

Gravitational scattering events, in which the path of an interstellar object is deflected by a pulsar or the solar system, give rise to reflex motion which can potentially be detected using pulsar timing. We determine the form of the timing signal expected from a gravitational scattering event, which is ramp-like and resembles the signal produced by a glitch or a gravitational wave burst with memory (BWM), and investigate the prospects for detecting such a signal using a pulsar timing array. The level of timing precision currently achieved for some millisecond pulsars makes it possible to detect objects as small as $10^{-10}$ solar masses, less than the mass of the dwarf planet Ceres, at impact parameters as large as 1 AU. The signals produced by gravitational scattering could provide independent constraints on models of dark matter involving asteroid-mass objects or subhalos, and should be considered as potential false positives in searches for BWMs.

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Ross J. Jennings, James M. Cordes, Shami Chatterjee. 2019-12-27. Detecting Gravitational Scattering of Interstellar Objects Using Pulsar Timing. https://doi.org/10.3847/1538-4357%2Fab64df

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