Thermal modelling of Advanced LIGO test masses

Abstract

High-reflectivity fused silica mirrors are at the epicentre of current advanced gravitational wave detectors. In these detectors, the mirrors interact with high power laser beams. As a result of finite absorption in the high reflectivity coatings the mirrors suffer from a variety of thermal effects that impact on the detectors performance. We propose a model of the Advanced LIGO mirrors that introduces an empirical term to account for the radiative heat transfer between the mirror and its surroundings. The mechanical mode frequency is used as a probe for the overall temperature of the mirror. The thermal transient after power build-up in the optical cavities is used to refine and test the model. The model provides a coating absorption estimate of 1.5 to 2.0 ppm and estimates that 0.3 to 1.3 ppm of the circulating light is scattered on to the ring heater.

14 pages, 9 figures

References in corpus (9)

• Observation of Gravitational Waves from a Binary Black Hole Merger
• Advanced Virgo: a 2nd generation interferometric gravitational wave detector
• Characterization of the LIGO detectors during their sixth science run
• Parametric Oscillatory Instability in Fabry-Perot (FP) Interferometer
• Observation of Parametric Instability in Advanced LIGO
• Overview of Advanced LIGO Adaptive Optics
• Compensation of Strong Thermal Lensing in High Optical Power Cavities
• First Demonstration of Electrostatic Damping of Parametric Instability at Advanced LIGO
• Analytical model for ring heater thermal compensation in the Advanced Laser Interferometer Gravitational-wave Observatory

Cited by in corpus (4)

• Advanced LIGO detector performance in the fourth observing run
• Imaging Scatterometer for Observing In-Situ Changes to Optical Coatings During Air Annealing
• Constraining temperature distribution inside LIGO test masses from frequencies of their vibrational modes
• Thermal Deformation Reduction in High-Power Interferometry with Higher-Order Laser Modes