Reports until 19:41, Thursday 23 August 2018
H1 ISC (ISC)
hang.yu@LIGO.ORG - posted 19:41, Thursday 23 August 2018 (43633)
ASC sensing matrix measurements

Jenne, Hang

We modified the old ASC sensing matrix code and did a measurement for the PIT dofs. The whole sensing matrix can be found at /ligo/home/hang.yu/Desktop/ASC/SenMtrx/rec/Aug232018225636UTC/html_rec_rad2W_1219100214.html. The calibration was based on some old scripts so we would need to double-check if they were still correct.

For now we just focus on the input-common arm dofs in PIT. For the three interferometrical dofs (currently we chose them to be INP1 -- > IM4, PRC2 --> PR2, and CHARD), the response matrix is

  REFL_A_RF9_I REFL_A_RF45_I REFL_B_RF9_I REFL_B_RF45_I POP_X_I
CHARD -0.56 -0.96 -0.44 -1 0.15
PRC2 (PR2) 0.22 -0.15 0.07 -0.12 -1
INP1 (IM4) 0.71 0.72 -0.72 -1 -0.03

This suggested that we might update the input matrix to for better decoupling the dofs:

REFL_A_RF45_I REFL_B_RF45_I POP_X_I  
1 0.7 0 CHARD
0 0 -0.05 PRC2
1 -1 0 INP1

We didn't finish the yaw measurement and the AS port signals did not have a good coherence. Will update the drives when we get a chance next time.