Interferometer_sensitivity_studies (General)swinkels - 22:47 Wednesday 02 April 2008 (20254)
Print this reportSome more magnetic injectionsThis afternoon, I repeated yesterday's measurement (see #20239) in the central building to check for repeatability. In this case, the coil was placed on the lower balcony in the north east corner (above the L-room). In theory, this measurement should be more or less independent of the place of the source.
Later in the evening, I did a similar measurement in the detection lab to check for any magnetic pick-up in the analog electronics. I was able to inject lines up to at least 800 Hz, but this required putting the coil right next to the rack, which is a good sign. To still get a sort of far-field measurement, I moved the coil as far away as possible while still being able to observe the lines. The final location was about 2 meter from the demodulation rack and about 1 meter from the ADC rack. The magnetometer MABDCE02 was placed in the mirror position. It might be possible that you are at the same time moving the NI mirror, but since this coupling should fall off with f^2, any remaining coupling at high frequencies should be due to the electronics.