9 research outputs found
Sensitivity Comparison of Searches for Binary Black Hole Coalescences with Ground-based Gravitational-Wave Detectors
Searches for gravitational-wave transients from binary black hole
coalescences typically rely on one of two approaches: matched filtering with
templates and morphology-independent excess power searches. Multiple
algorithmic implementations in the analysis of data from the first generation
of ground-based gravitational wave interferometers have used different
strategies for the suppression of non-Gaussian noise transients, and targeted
different regions of the binary black hole parameter space. In this paper we
compare the sensitivity of three such algorithms: matched filtering with full
coalescence templates, matched filtering with ringdown templates and a
morphology-independent excess power search. The comparison is performed at a
fixed false alarm rate and relies on Monte-carlo simulations of binary black
hole coalescences for spinning, non-precessing systems with total mass 25-350
solar mass, which covers the parameter space of stellar mass and intermediate
mass black hole binaries. We find that in the mass range of 25 -100 solar mass
the sensitive distance of the search, marginalized over source parameters, is
best with matched filtering to full waveform templates, to within 10 percent at
a false alarm rate of 3 events per year. In the mass range of 100-350 solar
mass, the same comparison favors the morphology-independent excess power search
to within 20 percent. The dependence on mass and spin is also explored.Comment: 11 pages, 2 tables, 25 figure
Searching for stochastic gravitational waves using data from the two colocated LIGO Hanford detectors
Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a colocated detector pair is more sensitive to a gravitational-wave background than a noncolocated detector pair. However, colocated detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of colocated detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques to data taken by the two LIGO Hanford detectors, H1 and H2, during LIGO’s fifth science run. At low frequencies, 40–460 Hz, we are unable to sufficiently mitigate the correlated noise to a level where we may confidently measure or bound the stochastic gravitational-wave signal. However, at high frequencies, 460–1000 Hz, these techniques are sufficient to set a 95% confidence level upper limit on the gravitational-wave energy density of Ω(f) < 7.7 × 10[superscript -4](f/900 Hz)[superscript 3], which improves on the previous upper limit by a factor of ~180. In doing so, we demonstrate techniques that will be useful for future searches using advanced detectors, where correlated noise (e.g., from global magnetic fields) may affect even widely separated detectors.National Science Foundation (U.S.)United States. National Aeronautics and Space AdministrationCarnegie TrustDavid & Lucile Packard FoundationAlfred P. Sloan Foundatio
Oxygen-Hafnium-Neodymium Isotope Constraints on the Origin of the Talnakh Ultramafic-Mafic Intrusion (Norilsk Province, Russia)
Searching for stochastic gravitational waves using data from the two colocated LIGO Hanford detectors
Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a colocated detector pair is more sensitive to a gravitational-wave background than a noncolocated detector pair. However, colocated detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of colocated detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques to data taken by the two LIGO Hanford detectors, H1 and H2, during LIGO’s fifth science run. At low frequencies, 40–460 Hz, we are unable to sufficiently mitigate the correlated noise to a level where we may confidently measure or bound the stochastic gravitational-wave signal. However, at high frequencies, 460–1000 Hz, these techniques are sufficient to set a 95% confidence level upper limit on the gravitational-wave energy density of Ω(f)<7.7×10−4(f/900 Hz)3, which improves on the previous upper limit by a factor of ∼180. In doing so, we demonstrate techniques that will be useful for future searches using advanced detectors, where correlated noise (e.g., from global magnetic fields) may affect even widely separated detectors