camilla.compton@LIGO.ORG - posted 21:38, Thursday 01 June 2023 (70078)
O4 TCS Settings
In alog 69106 I listed the TCS changes up while at 76W input power but the final settings changed just before the Observing run started 69871 with the EX ring heater bring dropped from 1.3W to 1.2W/segment on 2023/05/24 11:56UTC. This was to avoid PI29.
This change increased the circulating power in the arms and the requested input power was dropped from 76W to 75W on 2023/05/31 70042.
The recorded input power at 76w requested seemed to change by up to 1W lock to lock, see attached. tagging PSL.
See attached plot that since the O4 run has started CO2 laser powers have been stable and the power into the vacuum has been stable within 0.05W.
|
Date
|
Power In |
IX
|
IY
|
EX
|
EY
|
CO2X
|
CO2Y
|
Notes
|
|
2023/04/26
04UTC/15UTC
|
76W |
-
|
-
|
1.3
|
-
|
-
|
-
|
|
|
2023/05/24
11UTC
|
- | - | - | 1.2 | - | - | - | Decreased EX RH to avoid PI29 |
|
2023/05/31
19UTC
|
75W |
0.44
|
0.0
|
1.2
|
1.2
|
1.7
|
1.7
|
O4 settings (Input power reduced) |
Images attached to this report
