The possible existence of intermediate-mass binary black holes (IMBBHs) in globular clusters (GCs) offers us a unique geometry in which to detect spacetime oscillations. For certain pulsar-IMBBH configurations possible within a GC, the usual far-field plane wave approximation for the IMBBH metric perturbation severely underestimates the induced pulse time-of-arrival (TOA) fluctuations. In this Letter, the expected TOA fluctuations induced by an IMBBH lying close to the line of sight between a pulsar and the Earth are calculated for the first time. For an IMBBH consisting of 10 and 103 MâŠ™ components, a 10 yr orbital period, and located 0.1 lt-yr from the Earth-pulsar line of sight, the induced TOA fluctuations will be of order 5-500 ns. Â© 2005. The American Astronomical Society. All rights reserved.
Fredrick A. Jenet, et. al., (2005) Pulsar timing and the detection of black hole binary systems in globular clusters.Astrophysical Journal627:2L125. DOI: http://doi.org/10.1086/431949