Reports until 16:51, Sunday 08 November 2015
H1 General (OpsInfo)
nutsinee.kijbunchoo@LIGO.ORG - posted 16:51, Sunday 08 November 2015 - last comment - 17:58, Sunday 08 November 2015(23222)
RF45 mod decreased by 2dB

Since the data is probably going to be cat1 vetoed anyway, I decided to help the situation the only way I know how. The RF45 Mod was 23.2 dB, now at 21.2 dB. I dropped out of Observing when I did this. I asked Kiwamu to make sure that it's okay to leave the gain at this value.

 

The glitches stopped for about 15 minutes. While writing this alog it seems to be coming back again. I might decrease the gain even further if it doesn't stop.

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Comments related to this report
nutsinee.kijbunchoo@LIGO.ORG - 16:55, Sunday 08 November 2015 (23223)

RF45 mod gain decreased to 20.2 dB.

evan.hall@LIGO.ORG - 16:55, Sunday 08 November 2015 (23224)

If you go more than 2 dB lower than nominal you risk unlocking the interferometer. There is also no clear evidence that reducing the modulation depth fixes this issue, but of course it doesn't hurt to get another data point.

nutsinee.kijbunchoo@LIGO.ORG - 16:58, Sunday 08 November 2015 (23225)

I can see that DHARD isn't happy. I put the gain back to 21.2dB.

nutsinee.kijbunchoo@LIGO.ORG - 16:59, Sunday 08 November 2015 (23226)

I just noticed SUSETMY has timing error. I hit Diag Reset to clear this. ETMY saturation continues.

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nutsinee.kijbunchoo@LIGO.ORG - 17:17, Sunday 08 November 2015 (23227)

Observing again at 01:20 UTC. ETMY continues to saturate. I don't think there's anything else I can do to help.... If you have an idea please call the control room.

nutsinee.kijbunchoo@LIGO.ORG - 17:32, Sunday 08 November 2015 (23228)

Decreased RF45 MOD to 20.2 dB again after RF45 amplitude increased and stuck there causing DARM noise floor to rise. Forgot to go out of Observing when changing the gain.

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nutsinee.kijbunchoo@LIGO.ORG - 17:58, Sunday 08 November 2015 (23229)

I called Mike and he suggested I take the ifo out of Observing and wait until the RF45 situation gets better. The BSN range is at 15-20 Mpc at the moment. RF45 MOD set to 21.2 dB.