Camilla, Sheila

Following up on the high noise coil driver test in 53253, we again locked to the nominal noise state with our coil drivers in high noise and attempted to switch them to the nominal driver state a few suspensions at a time, I caused a lockloss when trying to swtich ETMY coils.  

Based on the measurements we did get, the quad pums are the largest contribution to this noise, the beam splitter also makes a measureable but small contribution.  The projections in the second attachment are based on difference in the ASDs between different coil states, and assume that the noise scales with the analog filters, which wouldn't be a correct assumption for a drive dependent noise.  This is generally about a factor of 2-3 higher than the projection in the noise budget, and is about a factor of 5 below our noise budget residual.  

Times:

• BS, PRM, PR2, SRM, SR2 and all quads in acquisition states: 22:08:29 UTC
• PRM, PR2, SRM, SR2 and all quads in acquisition states: 22:14:30 UTC (bs switched)
• all quads in acquisition states: 22:18:00 UTC (bs + hsts switched)