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Updated: May 25, 2026
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
Directional limits on persistent gravitational waves using LIGO S5 science data
J Abadie1, B P Abbott, R Abbott
1LIGO-California Institute of Technology, Pasadena, California 91125, USA.
Physical Review Letters
|January 17, 2012
Summary
Researchers searched for persistent gravitational waves (GWs) using LIGO data but found no detections. They established upper limits on GW strain, providing the first such limits for extended sources.
Area of Science:
- * Astrophysics
- * Gravitational Wave Astronomy
- * Data Analysis
Background:
- * The gravitational-wave (GW) sky may contain both pointlike sources and stochastic backgrounds.
- * Detecting persistent GWs is crucial for understanding astrophysical phenomena.
Purpose of the Study:
- * To conduct directional searches for persistent GWs using LIGO S5 data.
- * To set upper limits on GW strain power for pointlike and extended sources.
- * To establish limits on GW strain from specific celestial targets.
Main Methods:
- * Utilized data from the LIGO S5 science run.
- * Performed two distinct directional searches: one for pointlike sources and another for arbitrary extended sources.
- * Calculated 90% confidence level (C.L.) upper-limit maps of GW strain power.
Main Results:
- * No evidence for the detection of persistent GWs was found.
- * Established upper limits on GW strain power for pointlike sources (2–20×10⁻⁵⁰ strain²/Hz) and extended sources (5–35×10⁻⁴⁹ strain²/Hz·sr).
- * Set 90% C.L. limits on narrow-band root-mean-square GW strain for targets like Sco X-1, SN 1987A, and the Galactic center, reaching ≈7×10⁻²⁵ near 160 Hz.
Conclusions:
- * The searches did not yield a detection of persistent gravitational waves.
- * The study provides the first upper limits for extended GW sources.
- * The results constrain astrophysical models and improve sensitivity for future GW searches.
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