LIGO Document T1600438-v1
- At the AEI-10m Prototype in Hannover, Germany, the sensor noise of several L-22D and L-4C geophones (from Sercel) was measured in a huddle test. New amplifier electronics were employed in order to drastically reduce electronic noise below 1 Hz. With some minor modifications to our new front-end electronics, we were able to achieve sensor noise limited only by Johnson-noise of the sensing coil and the (white) input voltage noise of the first-stage amplifier, an OPA188. Each of these noise sources contributes approximately equally. The sensitivity improvement from L-22Ds with our initial electronics to L-4Cs with new and refined electronics was more than a factor of 10 at 1 Hz and more than a factor of 100 at 0.1 Hz and below.
DCC Version 3.4.3, contact
Document Database Administrators