2008/05/28 by Karen M. Lewis, Penny D. Sackett, Rosemary A. Mardling · 2 citations
Engineering · Physics and Astronomy · #Advanced Frequency and Time Standards #Astronomy #Astrophysics #Binary number #Binary pulsar #Geophysics and Sensor Technology #Millisecond pulsar #Orbital inclination #Physics #Planet #Planetary mass #Planetary system #Pulsar #Pulsar planet #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/592743
11 pages, 3 figures
arxiv created 2008/05/28 · openalex publication_date 2008/09/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The perturbation caused by planet-moon binarity on the time-of-arrival signal of a pulsar with an orbiting planet is derived for the case in which the orbits of the moon and the planet-moon barycenter are both circular and coplanar. The signal consists of two sinusoids with frequency (2 n p − 3 n b ) and (2 n p − n b ), where n p and n b are the mean motions of the planet and moon around their barycenter, and the planet-moon system around the host, respectively. The amplitude of the signal is the fraction sin I [ 9( M p M m )/16( M p + M m ) 2 ][ r / R ] 5 of the system crossing time R / c , where M p and M m are the masses of the planet and moon, r is their orbital separation, R is the distance between the host pulsar and planet-moon barycenter, I is the inclination of the orbital plane of the planet, and c is the speed of light. The analysis is applied to the case of PSR B1620–26b, a pulsar planet, to constrain the orbital separation and mass of any possible moons. We find that a stable moon orbiting this pulsar planet could be detected, if its mass were >5% of its planet's mass, and if the planet-moon distance were ~2% of the planet-pulsar separation.