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تسجيل مستخدم جديدImproved limits on a stochastic gravitational-wave background and its anisotropies from Advanced LIGO O1 and O2 runs
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We integrate the entire, publicly available, Advanced LIGO (ALIGO) data set to obtain maximum-likelihood constraint maps of the Stochastic Gravitational-Wave Background (SGWB). From these we derive limits on the energy density of the stochastic background $Omega_{rm GW}$, and its anisotropy. We find 95% confident limits $Omega_{rm GW} < 5.2times 10^{-8}$ at $50$ Hz for a spectral index $alpha=2/3$ consistent with a stochastic background due to inspiral events and $Omega_{rm GW} < 3.2times 10^{-7}$ for a scale (frequency) invariant spectrum. We also report upper limits on the angular power spectra $C_ell$ for three broadband integrations of the data. Finally we present an estimate where we integrate the data into ten separate spectral bins as a first attempt to carry out a model-independent estimate the SGWB and its anisotropies.
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Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the universe that is unavailable through standard ele
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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 gr
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We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGOs and Advanced Virgos third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing ru
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