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arXiv · 0804.4131

Experimental investigation of a control scheme for a zero-detuning resonant sideband extraction interferometer for next-generation gravitational-wave detectors

Fumiko Kawazoe·Mitsuhiro Fukushima·Seiji Kawamura·Volker Leonhardt·Osamu Miyakawa·Tomoko Morioka·Atsushi Nishizawa·Shuichi Sato·Kentaro Somiya·Akio Sugamoto·Toshitaka Yamazaki
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Abstract

Some next-generation gravitational-wave detectors, such as the American Advanced LIGO project and the Japanese LCGT project, plan to use power recycled resonant sideband extraction (RSE) interferometers for their interferometer's optical configuration. A power recycled zero-detuning (PRZD) RSE interferometer, which is the default design for LCGT, has five main length degrees of freedom that need to be controlled in order to operate a gravitational-wave detector. This task is expected to be very challenging because of the complexity of optical configuration. A new control scheme for a PRZD RSE interferometer has been developed and tested with a prototype interferometer. The PRZD RSE interferometer was successfully locked with the control scheme. It is the first experimental demonstration of a PRZD RSE interferometer with suspended test masses. The result serves as an important step for the operation of LCGT.

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Fumiko Kawazoe, Mitsuhiro Fukushima, Seiji Kawamura, Volker Leonhardt, Osamu Miyakawa, Tomoko Morioka, Atsushi Nishizawa, Shuichi Sato, Kentaro Somiya, Akio Sugamoto, Toshitaka Yamazaki. 2008-04-25. Experimental investigation of a control scheme for a zero-detuning resonant sideband extraction interferometer for next-generation gravitational-wave detectors. https://doi.org/10.1088/0264-9381%2F25%2F19%2F195008

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