This is a very quick first look at the ASC performance with the HAM1 ISI. Jim is still working on bringing the ISI up to full performance, but the first attached plot compares the INP1 P and CHARD P error spectra from March 31 just before the vent and yesterday, when we locked to full power and low noise with HAM1 in the isolated state.

Before the vent, we were running feedforward of the HAM1 L4Cs to CHARD, INP1 and PRC2. PRC2 is now on the POP sensor, and CHARD and INP1 both use a combination of the REFL WFS 45 MHz signals. The large peak around 20 Hz before the vent appears to have reduced in INP1 P and shifted down in frequency in CHARD P. The second attachment shows that large peak in CHARD P is coherent with the HAM1 GS13s, from about 10 to 20 Hz, especially with RX, RY, RZ, and Z.

There is also a peak at 6 Hz, which we know is a vertical resonance of the RMs, 84712.