Upper Limits on the Stochastic Gravitational-Wave Background from Advanced LIGO's First Observing Run
A wide variety of astrophysical and cosmological sources are expected to contribute to a stochastic gravitational-wave background. Following the observations of GW150914 and GW151226, the rate and mass of coalescing binary black holes appear to be greater than many previous expectations. As a result, the stochastic background from unresolved compact binary coalescences is expected to be particularly loud. We perform a search for the isotropic stochastic gravitational-wave background using data from Advanced Laser Interferometer Gravitational Wave Observatory’s (aLIGO) first observing run. The data display no evidence of a stochastic gravitational-wave signal. We constrain the dimensionless energy density of gravitational waves to be Ω0<1.7×10−7 with 95% confidence, assuming a flat energy density spectrum in the most sensitive part of the LIGO band (20–86 Hz). This is a factor of ∼33times more sensitive than previous measurements. We also constrain arbitrary power-law spectra. Finally, we investigate the implications of this search for the background of binary black holes using an astrophysical model for the background.
Chmiel, Theresa; Wade, Leslie; Wade, Madeline; and al., et, "Upper Limits on the Stochastic Gravitational-Wave Background from Advanced LIGO's First Observing Run" (2017). Physical Review Letters 118(12). Faculty Publications. Paper 252.
Physical Review Letters