Sheila, Jenne, Matt, Rob, Evan, Lisa

Several things happened today, more details will be posted later:
we locked several times in low noise (note: ASC in the old configuration with DC (not RF90MHz) centering, see week-end entries for more details): the best range we saw today was about ~70 Mpc, due to some peaks in the spectrum higher than usual -- the 290 Hz was particularly higher than during O1;
in low noise Sheila made several ISI shaking tests, Robert did some investigations in parallel as well;
we looked at the coupling into the OMC at full power: this measurement needs to be repeated to make sure the conclusion we get is right, as the inferred coupling to the OMC would be significantly lower than what assumed from previous measurements;
Jenne took some DHARD open loop transfer functions as function of the DARM offset;
some off-line investigations to get hints of the mystery noise happened as well, more details will follow.
 
Some of these things are not finished as an earthquake hit us around 10pm local time; we waited for two hours for the noise to go down again, but we couldn't really relock robustly afterwards, even when the ground motion seemed back to normal (to be investigated). 

Some items for our to-do-list that came up tonight (to be merged with what we already have on the control room whiteboard) are:
inspired by Kiwamu's analysis, modulate the vertical position of optics and look for changes in the DARM noise;
(new entry): look at the DARM rms, and see if there is some loop optimization that can be done to minimize it (in particular, check if rms optimization advocated by Jeff at the last commissioning workshop happened or not);
in-depth analysis of frequency noise, in particular look for saturations in the common mode board;
close the loop on this OMC coupling, and if it is real, distinguish between mode mismatch vs misalignment - if it turns out that the alignment into the OMC is bad, resurrect deacon alignment (ECR already submitted and approved).