Vibration Measurements of the Beamtube

Document #:

LIGO-T1400384-v2

Document type:

T - Technical notes

Abstract:

Vibration measurements of the beam tube are compared for the bare tube, the tube insulated with new R10 insulation covered with a 0.016" aluminum jacket and the tube covered with the original insulation. The new insulation does not damp the acoustically driven normal modes of the tube as well as the original insulation. A detailed analysis using this data needs to be made to determine if the current test mass mirrors with their periodic grating in the HR coating will cause excess scattering noise from the beamtube motion.

Files in Document:

• Vibration measurements of the beamtube.pdf (931.5 kB)

Topics:

• Observatory Facilities
• System Engineering

Author Groups:

• LSC

Notes and Changes:

Revised version of document
Corrects an error in the calibration of the accelerometers and includes an estimate of the equivalent displacement noise in the operating interferometer from the scattering by the baffles driven by the measured motion

Referenced by: