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arXiv · 1103.0346

Upper Limit on Gravitational Wave Backgrounds at 0.2 Hz with Torsion-bar Antenna

Koji Ishidoshiro·Masaki Ando·Akiteru Takamori·Hirotaka Takahashi·Kenshi Okada·Nobuyuki Matsumoto·Wataru Kokuyama·Nobuyuki Kanda·Yoichi Aso·Kimio Tsubono
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Abstract

We present the first upper limit on gravitational wave (GW) backgrounds at an unexplored frequency of 0.2 Hz using a torsion-bar antenna (TOBA). A TOBA was proposed to search for low-frequency GWs. We have developed a small-scaled TOBA and successfully found Ωgw(f) < 4.3 \times 1017 at 0.2 Hz as demonstration of the TOBA's capabilities, where Ωgw (f) is the GW energy density per logarithmic frequency interval in units of the closure density. Our result is the first nonintegrated limit to bridge the gap between the LIGO band (around 100 Hz) and the Cassini band (10-6 - 10-4 Hz).

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Koji Ishidoshiro, Masaki Ando, Akiteru Takamori, Hirotaka Takahashi, Kenshi Okada, Nobuyuki Matsumoto, Wataru Kokuyama, Nobuyuki Kanda, Yoichi Aso, Kimio Tsubono. 2011-03-02. Upper Limit on Gravitational Wave Backgrounds at 0.2 Hz with Torsion-bar Antenna. https://doi.org/10.1103/physrevlett.106.161101

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