While LLO was down:

1) We shook the input beam tube at low frequencies: no significant coupling below 8 Hz was found.

2) Tapped on top of a lot of chambers to see if falling metal oxide dust might produce fast transients like blip glitches: some transients were produced, more analysis to come.

3) We shook ISCT1 at 12.5 Hz (about the sway resonance of the table) and injected at an amplitude that produced clear scattering harmonic peaks in the 200 Hz region (consistent with motion amplitude of about 1 micron). This required about 40 times background velocity (see plot). We found dumped beams that were bight in the viewer and blocked them with black glass while watching the scattering peaks.  The scattering harmonics seemed to mostly go away when we blocked a particular beam hitting one of the razor blade dumps (see figure). The razor blade dump seems to dominate the scattering and may not be quite good enough. We should replace it with a black glass dump with the reflected beam dumped on a razor blade dump.

Robert, Jenne, Vaishali, Heather