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This post shows the results of the magnetic injections from the far-field, performed several weeks ago. Fig 1 shows the resulting transfer-functions from magnetic field to h, compared to some older measurements. We repeated one measurement at the WE, where no magnets had been changed yet. This measurement reproduces pretty well. We also repeated a measurement in the central building, where the NI lateral magnets were removed. This transfer function is about a factor 5 lower than before. At high frequencies, we were probably fitting a sine to the background noise of B1, so this should give an upper limit.

I then recalculated the magnetic noise projection, using the new TF for the central building and the old ones for the end buildings. For the sensitivity and the noise of the magnetometers I used data from the night of the 5th of May, when the ITF was in a very good shape. Fig 2 shows the old projection, fig 3 the new one. If the new projection is correct, we are currently dominated by the NE. The prediction for the 50 Hz line is still ok, the 11 Hz and the 50 Hz sidebands are predicted slightly too low. Finally, fig 4 shows the coherence between the magnetometers and the dark-fringe from the same night.