Advanced Virgo suspended optical bench inside its vacuum enclosure (January 2016))

The researcher is tuning the position of a mirror on an optical bench. For Advanced Virgo, new optical benches have been suspended and put in vacuum. The mechanics of the suspension is visible on the top part still opened. On-board electronics is attached below the suspended bench to reduce the number of (white) electrical cables going along the suspension.

Credits: Cyril Frésillon/Virgo/Photothèque CNRS

Album: Instruments – Laser&Optics

Tags: #multi-stage attenuator system #Optical bench #suspension #Virgo

The researcher is checking the laser beam alignment on a mirror of an optical bench. The infrared beam is not visible by human eyes, a dedicated visualisation card allows to see the beam position.

Credits: Cyril Frésillon/Virgo/Photothèque CNRS

Album: Instruments – Laser&Optics

Tags: #Advanced Virgo #laser #Optical bench #infrared

The researchers are preparing the optical bench to be inserted inside the vacuum enclosure and suspended to the mechanical attenuator on top of the enclosure, called minitower. A clean area has been built around the minitower to keep the optical elements out of dust.

Credits: Cyril Frésillon/Virgo/Photothèque CNRS

Album: Instruments – Laser&Optics

Tags: #Advanced Virgo #minitower #Optical bench #installation

Assembly of the optical bench in a clean room. This bench has a “diameter” of about 88 cm. It has been suspended to a suspension in April 2015.
This bench collects the laser beam at the asymmetric port of the Virgo interferometer, the one whose power will vary when a gravitational wave passes by. The beam size is reduced from 2 cm on the first big optical lens down to 300 µm on a small optical cavity called mode-cleaner cavity. The beam power is then measured on a photodiode placed on another optical bench.

Credits: Virgo Collaboration/LAPP

Album: Instruments – Laser&Optics

Tags: #Optical bench