Virgo Logbook

I looked into the details of this test, following up with the suggestions during the commissioning meeting. I include here the most relevant plots.

Results of the channels identified are attached in the figures. I did not identify any disturbance in h(t) or most of the ENV RF channels. I see two features in the RF channels, a line (120Hz) and an overall change (8:35:25). Yet, the line starts two minutes before the start of the WIFI test (8:16:10), thus discarding a connection with it. Instead, the channel ENV_WEB_RF_8MHz_I presents an overall effect that seems to coincide with the start of the RS485 test. This does not seem to have a large impact of Hrec or the BNSrange. Since the interferometer unlocked just after the test, I can not verify if this effect stays once the RS485 tests finishes.

To understand better, I analysed the data taken during the test in April 2025. The RS485 part of the test took place from : Started RS485 transmission, Short test just to check RS485 is still working (UTC: 2025-04-30 07:56:41.061210 UTC) to the moment where the transmission was stopped at UTC: 2025-04-30 07:58:14.682536 UTC. The plot is attached. I do not see any effect.

Regarding glitches, Nicola kindly run Omicron and identified several glitches during the test period, none close enough to the steps of the test to establish a connection. In addition, the rate of glitches does not seem abnormal during the duration of the test.

The Omicron triggers that have an SNR > 8 in that GPS range are

> # time-clustered triggers, dt = 0.10000s
> # starting time [GPS]
> # peak time [GPS]
> # ending time [GPS]
> # duration [s]
> # starting frequency [Hz]
> # peak frequency [Hz]
> # ending frequency [Hz]
> # bandwidth [Hz]
> # SNR [-]
> 1449476546.2031 1449476546.6172 1449476547.1934 0.9902 43.98 227.04 1627.79 1583.81 16.42
> 1449477589.5000 1449477590.2891 1449477591.0938 1.5938 16.00 227.04 1903.46 1887.46 13.31
> 1449477702.3750 1449477703.9102 1449477705.5000 3.1250 16.00 40.42 1674.76 1658.76 467.72
> 1449477762.0625 1449477762.1719 1449477762.2812 0.2188 120.88 161.38 200.40 79.53 11.39
> 1449478206.7500 1449478206.8691 1449478206.9688 0.2188 18.94 93.88 200.40 181.47 13.62
> 1449478218.9062 1449478218.9844 1449478219.0625 0.1562 143.07 161.38 237.19 94.12 9.04

After all these results, we can say that the tests had no visible disturbance. Yet, future test should pay attention to the channel ENV_WEB_RF_8MHz_I channel when the RS485 test is done.