[Cheryl, Jenne]

We're back in Observe.  

We were a little fooled by DRMI ASC today, thinking that we needed to redo initial alignment a few times - we didn't.  The problem seems to be that with the new alignment, the POP_A QPD is quite close to the edge (0.8ish in pit) when we have DRMI locked, even if we've just done a fresh alignment (or three...).  When PRC1 comes on with that large of an error signal and its nominal gain, it pulls the PRM quite hard over and the rest of the ASC fails to follow along.  What ended up working this acquisition was turning on the FM1 -20dB filter for PRC1 pit and having a much longer DRMI ASC convergence time. 

I checked that for the 30 hour lock this had been true, and we must have just squeaked by because the ASC didn't cause a lockloss.  I haven't checked times from before last Tuesday, but I suspect that the POP QPD may not have been as close to the edge before we arrived at our new alignment.  Or, something in the initial alignment is leaving the PRM farther away from its DRMI ASC position than it used to.