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arXiv · 2006.06907

Search for gravitational waves from five low mass X-ray binaries in the second Advanced LIGO observing run with an improved hidden Markov model

Hannah Middleton·Patrick Clearwater·Andrew Melatos·Liam Dunn
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Abstract

Low mass X-ray binaries are prime targets for continuous gravitational wave searches by ground-based interferometers. Results are presented from a search for five low-mass X-ray binaries whose spin frequencies and orbital elements are measured accurately from X-ray pulsations: HETE J1900.1-2455, IGR J00291+5934, SAX J1808.4-3658, XTE J0929-314, and XTE J1814-338. Data are analysed from Observing Run 2 of the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO). The search algorithm uses a hidden Markov model to track spin wandering, the $\mathcal{J}$-statistic maximum likelihood matched filter to track orbital phase, and a suite of five vetoes to reject artefacts from non-Gaussian noise. The search yields a number of low-significance, above threshold candidates consistent with the selected false-alarm probability. The candidates will be followed up in subsequent observing runs.

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Hannah Middleton, Patrick Clearwater, Andrew Melatos, Liam Dunn. 2020-06-12. Search for gravitational waves from five low mass X-ray binaries in the second Advanced LIGO observing run with an improved hidden Markov model. https://doi.org/10.1103/physrevd.102.023006

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