Upper Limits on A Stochastic Gravitational-Wave Background Using LIGO and Virgo Interferometers At 600-1000 Hz

J. Abadie, LIGO - California Institute of Technology
B. P. Abbott, California State University Fullerton
R. Abbott, University of Glasgow
T. D. Abbott, Universite de Savoie
M. Abernathy, Complesso Universitario di Monte sant'Angelo
T. Accadia, University of Naples Federico II
F. Acernese, University of Salerno
C. Adams, California Institute of Technology
R. Adhikari, Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
C. Affeldt, Leibniz University Hannover
M. Agathos, National Institute for Subatomic Physics
K. Agatsuma, National Institutes of Natural Sciences - National Astronomical Observatory of Japan
P. Ajith, University of Wisconsin-Milwaukee
B. Allen, University of Florida
E. Amador Ceron, University of Birmingham
D. Amariutei, National Institute for Nuclear Physics
S. B. Anderson, National Science Foundation
W. G. Anderson, Montana State University
K. Arai, European Gravitational Observatory
M. A. Arain, Syracuse University
M. C. Araya, Massachusetts Institute of Technology
S. M. Aston, Observatoire de Paris
P. Astone, Columbia University
D. Atkinson, Sezione di Pisa
P. Aufmuth, University of Pisa
C. Aulbert, Stanford University
B. E. Aylott, Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences
S. Babak, University of Texas at Brownsville
P. Baker, San Jose State University
G. Ballardin, Lomonosov Moscow State University

Abstract

A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600-1000 Hz, we obtained a 95% upper limit on the amplitude of ΩGW(f) ≥Ω3(f/900Hz)3, of Ω3<0.32, assuming a value of the Hubble parameter of h100≥0.71. These new limits are a factor of seven better than the previous best in this frequency band.