GWADW2026 - Gravitational-Wave Advanced Detector Workshop

Attenuating Jitter in the LIGO Hanford Detector

Not scheduled

15m

Hotel Hermitage, La Biodola, Isola d'Elba

Presentation Optical Design Optical Design

Speaker

Dr Jennifer Wright (LIGO Hanford Observatory)

Description

Jitter noise limits the LIGO H1 sensitivity between 100 and 500 Hz and L1 below 40 Hz. This is caused by motion in the pointing of the input beam from the in-air laser enclosure, relative to the rest of the detector which is in vacuum. This beam jitter imposes first order higher order modes on the light, and couples into the output of the detector as intensity noise due to imperfections in the mode-matching between the arms of the detector.

For O5 an extra input resonant cavity has been designed and commissioned in H1 which suppresses this noise. This ‘jitter attenuation cavity’ sits in the vacuum system between the main laser and the input mode cleaner and rejects first order spatial modes before they reach the input mode cleaner.