Abstract
A pivotal aspect in increasing the sensitivity of the Advanced LIGO detectors to allow the first gravitational wave detection, GW150914, was the installation of the monolithic fused silica suspensions. The 40 kg test mass suspended by four 400 μm fused silica fibres lowers the thermal noise as compared to initial LIGO. There is a desire for the use of thinner fibres to suspend smaller optics for other experiments of interest to the gravitational wave community that the current aLIGO fibre pulling machine is not capable of. We present here an overview of a new CO2 laser-based micron scale diameter fibre pulling machine developed at the University of Glasgow, based on the principals of our current aLIGO fibre pulling machine. We also discuss the upgraded fibre characterisation apparatus for dimensional and strength testing. It was found that fibres with a minimum diameter between 7.6 and 9.3 μm had an average breaking stress of 2.7 GPa and a Young’s modulus value of 63.3 GPa, which is lower than the accepted bulk value of 72 GPa. Fibres with an average diameter between 13.2 and 17.8 μm had higher breaking stress and Young’s modulus values ranging between 3.7–4.0 GPa and 71.8–75.9 GPa, respectively.
Highlights
Long baseline interferometers are currently used to detect gravitational waves radiating from massive astronomical objects in our universe by sensing the displacement of the two suspended mirrors at the end of each arm [1,2,3]
The Laser interferometer gravitational-wave observatory (LIGO) Scientific Collaboration announced in February 2016 their first detection of a gravitational wave signal at the two advanced LIGO detectors [4] in Hanford, Washington and Livingston, Louisiana that was radiated from the merger of two black holes— GW150914 [5]
A machine dedicated to the production of thin fused silica fibres was developed and characterised
Summary
Long baseline interferometers are currently used to detect gravitational waves radiating from massive astronomical objects in our universe by sensing the displacement of the two suspended mirrors at the end of each arm [1,2,3]. The Sagnac speed meter (SSM) is currently under construction at the University of Glasgow [16] The aim of this proof of concept experiment is to reduce back-action noise to allow better sensitivity in the low frequency region than is possible with a Michelson interferometer. This experiment aims to utilise fused silica fibres of diameters of 10 and 20 μm to suspend 1 g and 100 g optics, respectively. At the Albert Einstein Institute (AEI) in Hannover, the AEI 10 m prototype interferometer [17] is looking at increasing sensitivity through the use of squeezed light and will utilise 20 μm fused silica fibres to suspend 100 g optics. A new fused silica fibre pulling machine dedicated to producing short and thin fused silica fibres was developed together with suitable fibre characterisation apparatus
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.