In order to pursue the investigation about scattered light from INJ, during this morning Paolo moved SIB1 by injecting a line at 0.1 Hz on Sa_IB_F0_X on the DSP.  The GPS start is 1250511278 and the duration is 120 s. As shown in the first and second plots the bumps at 8 and 20 Hz on PRCL increased and shifted in frequency

We then analyzed the signals with Bas's script, finding the typical scattered light arches, but we didn't perform the projection on PRCL since we are not able to now to reconstruct correctly the real movement of the bench. We need to refine the anlysis of the data.