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arXiv · 1910.05097

Directed search for continuous gravitational-wave signals from the Galactic Center in the Advanced LIGO second observing run

Ornella J. Piccinni·P. Astone·S. D'Antonio·S. Frasca·G. Intini·I. La Rosa·P. Leaci·S. Mastrogiovanni·A. Miller·C. Palomba
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Abstract

In this work we present the results of a search for continuous gravitational waves from the Galactic Center using LIGO O2 data. The search uses the Band-Sampled-Data directed search pipeline, which performs a semi-coherent wide-parameter-space search, exploiting the robustness of the FrequencyHough transform algorithm. The search targets signals emitted by isolated asymmetric spinning neutron stars, located within 25-150 parsecs from the Galactic Center. The frequencies covered in this search range between 10 and 710 Hz with a spin-down range from $-1.8\times10^{-9}$ to $3.7\times10^{-11}$ Hz/s. No continuous wave signal has been detected and upper limits on the gravitational wave amplitude are presented. The most stringent upper limit at $95\%$ confidence level, for the Livingston detector, is $\sim 1.4 \times 10^{-25}$ at frequencies near 160 Hz. To date, this is the most sensitive directed search for continuous gravitational-wave signals from the Galactic Center and the first search of this kind using the LIGO second observing run.

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Ornella J. Piccinni, P. Astone, S. D'Antonio, S. Frasca, G. Intini, I. La Rosa, P. Leaci, S. Mastrogiovanni, A. Miller, C. Palomba. 2019-10-11. Directed search for continuous gravitational-wave signals from the Galactic Center in the Advanced LIGO second observing run. https://doi.org/10.1103/physrevd.101.082004

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