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arXiv · 0909.0010

Angular instability due to radiation pressure in the LIGO gravitational wave detector

Eiichi Hirose·Keita Kawabe·Daniel Sigg·Rana Adhikari·Peter R. Saulson
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Abstract

We observed the effect of radiation pressure on the angular sensing and control system of the Laser Interferometer Gravitational-Wave Observatory (LIGO) interferometer's core optics at LIGO Hanford Observatory. This is the first measurement of this effect in a complete gravitational wave interferometer. Only one of the two angular modes survives with feedback control, since the other mode is suppressed when the control gain is sufficiently large. We developed a mathematical model to understand the physics of the system. This model matches well the dynamics that we observe.

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Eiichi Hirose, Keita Kawabe, Daniel Sigg, Rana Adhikari, Peter R. Saulson. 2009-08-31. Angular instability due to radiation pressure in the LIGO gravitational wave detector. https://doi.org/10.1364/ao.49.003474

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