Validating gravitational-wave detections: The Advanced LIGO hardware injection system
Hardware injections are simulated gravitational-wave signals added to the Laser Interferometer Gravitational-wave Observatory (LIGO). The detectors' test masses are physically displaced by an actuator in order to simulate the effects of a gravitational wave. The simulated signal initiates a control-system response which mimics that of a true gravitational wave. This provides an end-to-end test of LIGO's ability to observe gravitational waves. The gravitational-wave analyses used to detect and characterize signals are exercised with hardware injections. By looking for discrepancies between the injected and recovered signals, we are able to characterize the performance of analyses and the coupling of instrumental subsystems to the detectors' output channels. This paper describes the hardware injection system and the recovery of injected signals representing binary black hole mergers, a stochastic gravitational wave background, spinning neutron stars, and sine-Gaussians.
© 2017 American Physical Society. Received 23 December 2016; published 27 March 2017. LIGO was constructed by the California Institute of Technology and Massachusetts Institute of Technology with funding from the National Science Foundation (NSF), and operates under cooperative agreement PHY-0757058. Advanced LIGO was built under Grant No. PHY-0823459. Computations were carried out on the Syracuse University HTC Campus Grid which is supported by NSF Grant No. ACI-1341006. Fellowship support from the LIGO Laboratory for S. K. is gratefully acknowledged. C. B. and D. A. B. acknowledge support from NSF Grant No. PHY-1404395. K. R. acknowledges support from NSF Grant No. PHY-1505932. E. T. acknowledges support from the Australian Research Council Grant No. FT150100281 and CE170100004. P. S. acknowledges support from NSF Grant No. PHY-1404121. J. R. S. acknowledges support from NSF Grant No. PHY-1255650. J. V. acknowledges support from the Science and Technology Facilities Council Grant No. ST/K005014/1. J. L. and R. O. acknowledge support from NSF Grant No. PHY 1505629. C. B. would like to thank Laura Nuttall for providing useful suggestions and Collin Capano for the software injection data in Sec. III A. This paper carries the LIGO Document Number LIGO-P1600285.
Published - PhysRevD.95.062002.pdf
Submitted - 1612.07864.pdf