This morning we switched off all motor crates of CEB, NEB and WEB from the panel switch. Upon relocking we can test if this has an effect in reducing some of the existing structures in the ranges 41-43 and 47-49 Hz.
After relocking we notice an improvement at a number of peaks in hrec in the range 30 to 60 Hz. In more detail:
- peaks that disappeared:
- 30.42 Hz (possibly associated to SDB1, see for example https://logbook.virgo-gw.eu/virgo/?r=63057)
- 32.31 Hz (small)
- 41.62 Hz
- 41.9 Hz
- 42.3 Hz
- 42.69 Hz
- 44.56 Hz
- 58 Hz (broad)
- peaks that reduced sensibly (approximately by a factor 2):
- 47.5 (probably associated to NI - https://logbook.virgo-gw.eu/virgo/?r=64453 and https://logbook.virgo-gw.eu/virgo/?r=64426)
- 47.7 (probably associated to CEB - https://logbook.virgo-gw.eu/virgo/?r=64453)
- 48.69
- 49.5 (apparently, to be confirmed with longer observations)
- 50.26 (same)
- peaks that did not change
- 41.44 Hz
- 46.7 Hz
- 48.07 (associated to WE)
- 48.34 (associated to WE)
- 48.63 (associated to CEB)
In the region around 70 Hz (where other modes of the F7 are located) no clear effects are seen (Figure 4).
A list of the on/off status of motor crates panel switches before today global switch off follows.
From top to bottom:
- SIB1
- n.1 ON
- n.2 ON
- n.3 ON
- PR
- n.1 ON
- n.2 ON
- n.3 ON
- n.4 OFF
- WI
- n.1 ON
- n.2 ON
- n.3 ON
- n.4 OFF
- n.5 OFF
- BS
- n.1 ON (we physically disconnected the power cable because when in "OFF" position the front panel light turned on)
- n.2 ON
- n.3 OFF
- NI
- n.1 ON
- n.2 ON
- n.3 ON
- n.4 OFF
- n.5 OFF
- SR
- n.1 ON
- n.2 ON
- n.3 OFF
- SDB1
- n.1 ON
- n.2 ON
- n.3 ON
- WE
- n.1 ON
- n.2 ON
- n.3 OFF
- n.4 OFF
- n.5 OFF
- NE
- n.1 ON
- n.2 ON
- n.3 ON
- n.4 OFF
- n.5 OFF