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Interferometric sensing of a commercial geophone

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 نشر من قبل Sam Cooper
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present a modified commercial L-4C geophone with interferometric readout that demonstrated a resolution 60 times lower than the included coil-magnet readout at low frequencies. The intended application for the modified sensor is in vibration isolation platforms that require improved performance at frequencies lower than 1 Hz. A controls and noise-model of an Advanced LIGO HAM-ISI vibration isolation system was developed, and it shows that our sensor can reduce the residual vibration by a factor of 70 at 0.1 Hz



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