Reports until 17:00, Thursday 17 September 2026
H1 AOS (ISC)
louis.dartez@LIGO.ORG - posted 17:00, Thursday 17 September 2026 (91957)
checking powers at ports

[Elenna, Louis]

After the HAM2 work (91959) finished today, we decided to double check AS port powers in a couple states. I trended back about a week to September 10, long before the RCG upgrade (91936). We are seeing a ~20% drop in counts on AS_A and AS_C in PRX_LOCKED and SRY. Also, our PRMI buildup right now is about 56. Last time we locked PRMI without ALS it was 52.

 

ALIGN_IFO State

Reference Time AS_A (ref) AS_A (now)

AS_A
now/ref (%)

AS_C (ref) AS_C (now) AS_C 
now/ref
(%)
POP_A_LF (ref) POP_A_LF (now) POP_A_LF
now/ref
(%)
PRX_LOCKED (N=32) 2026/09/10 15:35:29 UTC 1240 ct 992 ct 80 % 0.01465 W 0.0118 W 81 % --- --- ---
MICH_DARK_LOCKED (N=43) 2026/09/10 15:41:13 UTC --- --- --- --- --- --- 4.18 2.25 54 % *
SRY (N=62) 2026/09/10 15:31:56 UTC 5147 4127 80 % 0.061 W 0.05 W 82 % --- --- ---
SR2_ALIGN (N=59) 2026/09/10 15:35:35 UTC 1868.5 1797 96 % 0.0224 W 0.0216 W 96 % --- --- ---

 

* Not sure how comparable this number is since we don't know much about the centering on the LSC POP diode at the reference time. POPX pit & yaw are ~ -1 during this reference time stretch.