Results are presented from a semicoherent search for continuous gravitational waves from the brightest low-mass X-ray binary, Scorpius X-1, using data collected during the first Advanced LIGO observing run. The search combines a frequency domain matched filter (Bessel-weighted F-statistic) with a hidden Markov model to track wandering of the neutron star spin frequency. No evidence of gravitational waves is found in the frequency range 60-650 Hz. Frequentist 95% confidence strain upper limits, h095%=4.0×10-25, 8.3×10-25, and 3.0×10-25 for electromagnetically restricted source orientation, unknown polarization, and circular polarization, respectively, are reported at 106 Hz. They are ≤10 times higher than the theoretical torque-balance limit at 106 Hz.
Publication Source (Journal or Book title)
Physical Review D
Abbott, B., Abbott, R., Abbott, T., Acernese, F., Ackley, K., Adams, C., Adams, T., Addesso, P., Adhikari, R., Adya, V., Affeldt, C., Afrough, M., Agarwal, B., Agatsuma, K., Aggarwal, N., Aguiar, O., Aiello, L., Ain, A., Ajith, P., Allen, B., Allen, G., Allocca, A., Almoubayyed, H., Altin, P., Amato, A., Ananyeva, A., Anderson, S., Anderson, W., Antier, S., Appert, S., Arai, K., Araya, M., & Areeda, J. (2017). Search for gravitational waves from Scorpius X-1 in the first Advanced LIGO observing run with a hidden Markov model. Physical Review D, 95 (12) https://doi.org/10.1103/PhysRevD.95.122003