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arXiv · 0803.4094

Search for a stochastic background of 100-MHz gravitational waves with laser interferometers

Tomotada Akutsu·Seiji Kawamura·Atsushi Nishizawa·Koji Arai·Kazuhiro Yamamoto·Daisuke Tatsumi·Shigeo Nagano·Erina Nishida·Takeshi Chiba·Ryuichi Takahashi·Naoshi Sugiyama·Mitsuhiro Fukushima·Toshitaka Yamazaki·Masa-Katsu Fujimoto
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Abstract

This letter reports the results of a search for a stochastic background of gravitational waves (GW) at 100 MHz by laser interferometry. We have developed a GW detector, which is a pair of 75-cm baseline synchronous recycling (resonant recycling) interferometers. Each interferometer has a strain sensitivity of ~ 10^{-16} Hz^{-1/2} at 100 MHz. By cross-correlating the outputs of the two interferometers within 1000 seconds, we found h_{100}^2 Omega_{gw} < 6 times 10^{25} to be an upper limit on the energy density spectrum of the GW background in a 2-kHz bandwidth around 100 MHz, where a flat spectrum is assumed.

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Tomotada Akutsu, Seiji Kawamura, Atsushi Nishizawa, Koji Arai, Kazuhiro Yamamoto, Daisuke Tatsumi, Shigeo Nagano, Erina Nishida, Takeshi Chiba, Ryuichi Takahashi, Naoshi Sugiyama, Mitsuhiro Fukushima, Toshitaka Yamazaki, Masa-Katsu Fujimoto. 2008-08-09. Search for a stochastic background of 100-MHz gravitational waves with laser interferometers. https://doi.org/10.1103/physrevlett.101.101101

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