I made a few guardian changes this afternoon.
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Terra and I found that CHARD blends cannot be on durring the power up, so we are turning them off in DOWN, engage CHARD without them, and turn them on in Low noise ASC.
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I moved the step that switched off the SRM dither and moved it to WFS signals into its own state (SRM_ASC_HIGH_POWER). Yesterday Jenne and I found that we had to wait about 10 mintes after powering up to do this step, but it has to happen before NOISE_TUNNINGS.
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Since the ISS seems to have trouble engaging the second loop imediately after the IMC locks, I changed the request in ISC_LOCK DOWN to "LOCKED" and put a request in ISC_LOCK DRMI_LOCKED to set the MC to "ISS_ON"
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I think that I finally fixed the bug that meant that in ALIGN_IFO the dark michelson tried to grab which the optic was still swinging and woud get stuck saturating the BS.
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In DRMI ASC I added something that makes sure the ASC on switch is on (to avoid self inflicted locklosses)
A few things about ASC
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While moving SRM at high power, I looked for an SRM yaw signal in AS36 I, AS45 I, and REFL45. It seems like REFL 45 might be the best hope we have, but those signals are all dominated by a loop with a slow oscillation (a few second period), which might be PRC1 or a cross coupling between PRC1 and something else. If we can fix this, we might be able to find a decent SRM signal in REFL.
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It seems like the CHARD gain is set too low after low noise ASC, causing it to oscillate. There might have been a mix up in the guardian, but we should just measure the loop to check anyway.
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Our DC centerig loops have peaks with high coherence with DARM at a few hundred Hz. This might be because they are seeing the same jitter that couples to DARM, not because they impose the noise.