Andy, Josh, Laura

The RF45 noise reappeared for about a minute on Jan 4 at 21:35 UTC. It was a subtle manifestation - not obvious on the glitchgrams or in the range. It was the morphology that looks like repeated fast whistles. It showed up clearly in LSC-MOD_RF45_AM_CTRL but not any of the other RF9 or RF45 monitor channels. It also appeared in many LSC and ASC degrees of freedom, which is how hVeto found it. We'll check whether this is happening at other times, and keep an eye out in case it gets worse.

Attached are the appearance in DARM, and a spectrogram of the monitor channel around the time that this happened.