Heidelberg 2015 – wissenschaftliches Programm
Q 15.75: Poster
Montag, 23. März 2015, 17:00–19:00, C/Foyer
The AEI-SAS: Seismic isolation for the 10 m Prototype Interferometer — •Gerald Bergmann and the AEI 10m Prototype Team — Albert Einstein Institut Hannover
A 10 m arm length prototype interferometer is currently being set up at the AEI in Hanover, Germany. This facility will not only be used for developing novel techniques for future gravitational wave detectors, but furthermore it will provide a platform for high precision experiments such as measuring the standard quantum limit (SQL) of interferometry. To achieve the high requirements on displacement noise for these experiments very good isolation from seismic motion is required.
The first stage of seismic isolation for the 10 m prototype interferometer is a set of passively isolated optical tables. Geometric anti-spring filters provide vertical attenuation, and the tables are mounted on inverted pendulum legs which provide isolation in horizontal direction. Purely mechanically passive attenuation of more than 60 dB below 10 Hz was shown in first experiments. The table motion agrees very well with the predicted performance up to the lowest internal resonances above 25 Hz. Improvements of the AEI-SAS’s performance at those resonances are currently tested. Several sensors and a Suspension Platform Interferometer measure the residual table motion. These signals are used for actively controlling the tables. This can even provide isolation around the isolation system’s fundamental resonances.