Design and initial characterization of a compact, ultra high vacuum compatible, low frequency, tilt accelerometer

Area of Science:

• Geophysics
• Seismology
• Gravitational Wave Detection

Background:

• Advanced seismic attenuation systems require precise low-frequency corrections.
• Mechanical 1/f noise in polycrystalline metallic flexures limits accelerometer sensitivity.
• Gravitational wave observatories like LIGO need to mitigate seismic interference.

Purpose of the Study:

• To design and characterize a compact tilt accelerometer with high low-frequency sensitivity.
• To provide low-frequency corrections for the Advanced Laser Interferometer Gravitational Wave Observatory (LIGO) active seismic attenuation system.
• To develop a novel hinge mechanism to eliminate intrinsic mechanical 1/f noise.

Main Methods:

• Designed a tilt accelerometer utilizing a Tungsten Carbide ceramic knife-edge hinge.
• Detailed the design and construction of the accelerometer prototype.
• Discussed prototype data acquisition and control limitations.

Main Results:

• The ceramic knife-edge hinge proved to be metal-hysteresis-free.
• The instrument is free of 1/f noise generated by dislocation Self-Organized Criticality in metals.
• Demonstrated the potential for separating ground tilt from seismometer signals.

Conclusions:

• The developed tilt accelerometer effectively minimizes low-frequency noise using a ceramic hinge.
• This instrument can improve the accuracy of seismic attenuation systems in gravitational wave detectors.
• It offers a viable solution for correcting microseismic tilt effects in sensitive measurements.