Reports until 22:21, Thursday 04 May 2023
H1 TCS
camilla.compton@LIGO.ORG - posted 22:21, Thursday 04 May 2023 (69106)
TCS Changes while at 76W PSL input.

Below I have listed the relvant alogs for TCS changes while at 76W input power. Alog 68491 listed the TCS changes with 60W input power. 

I'm not documenting between 7th April and 13th April as at that time we were experimenting with 70 and 78W locks.

Ring heater powers are per segment. CO2Y stayed at 1.7W throughout apart from during CO2 tests.
ITMX and ITMY ring heaters stayed at 0.44W and 0.0W throughout.
 
Note the times in between a lot of these changes and measurements are extremely close so I would take some values with a gain of salt. Where I have listed two times, the change was taken in multiple smaller steps.
 
Date
IX
IY
EX
EY
CO2X
CO2Y
Notes
2023/04/13
0.44
0.0
1.2
1.2
1.7
1.7
Starting values.
We did some CO2 common and diff steps here, could make IFO worse but not better 68643.
2023/04/14 00UTC/06UTC
 
 
1.3
1.1
 
 
68676 contrast defect = 1.6mW.
2023/04/14
21UTC
 
 
 
1.0
 
 
68715 HOMs are coming together
2023/04/17 20UTC/01UTC+1
 
 
1.7
0.6
 
 
68777 68755 Aimed to get HOM peaks on top of each other but they went opposite way.
2023/04/18
23UTC
 
 
1.7
1.7
 
 
68810 Aimed to squash HOM,  this change moved the peaks below the PI forest but dropped PRG by 20%
2023/04/19
02UTC
 
 
1.4
1.0
 
 
68813  68812 2.2mW contrast defect, higher than 1.3/1.1W settings so lowering more.
2023/04/19
07UTC
 
 
1.3
1.0
 
 
68813 Reverting settings.
2023/04/19
19UTC
 
 
 
1.1
 
 
68859 Gave us a reduced 1.7mW contrast defect
2023/04/20
21UTC
 
 
 
1.2
 
 
68875 Reduced high freq noise. Moves HOM further apart.
2023/04/21
12UTC
 
 
 
 
 
 
68884 Pulsed SR3 Heater, 2W for 10minutes
2023/04/24
18UTC/21UTC

 

 

 

 

4.0

 

68995 69027 2.2mW contrast defect
2023/04/26
04UTC/15UTC
0.44
0.0
1.3
1.2
1.7
1.7
Final Settings 69032