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arXiv · 1608.02934

Overview of Advanced LIGO Adaptive Optics

Abstract

This is an overview of the adaptive optics used in Advanced LIGO (aLIGO), known as the thermal compensation system (TCS). The thermal compensation system was designed to minimize thermally-induced spatial distortions in the interferometer optical modes and to provide some correction for static curvature errors in the core optics of aLIGO. The TCS is comprised of ring heater actuators, spatially tunable CO$_{2}$ laser projectors and Hartmann wavefront sensors. The system meets the requirements of correcting for nominal distortion in Advanced LIGO to a maximum residual error of 5.4nm, weighted across the laser beam, for up to 125W of laser input power into the interferometer.

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Aidan F. Brooks, Benjamin Abbott, Muzammil A. Arain, Giacomo Ciani, Ayodele Cole, Greg Grabeel, Eric Gustafson, Chris Guido, Matthew Heintze, Alastair Heptonstall, Mindy Jacobson, Won Kim, Eleanor King, Alexander Lynch, Stephen O'Connor, David Ottaway, Ken Mailand, Guido Mueller, Jesper Munch, Virginio Sannibale, Zhenhua Shao, Michael Smith, Peter Veitch, Thomas Vo, Cheryl Vorvick, Phil Willems. 2016-08-08. Overview of Advanced LIGO Adaptive Optics. https://doi.org/10.1364/ao.55.008256

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