Reports until 21:57, Monday 25 March 2019
H1 ISC (ISC)
craig.cahillane@LIGO.ORG - posted 21:57, Monday 25 March 2019 (47864)
March 25th DARM sensing plant measurement
Jenne stepped down the ITM ring heaters in common today, and Keita okayed some commissioning time, so I checked on the DARM plant.
We are still running with pro-spring detuning.  From the measurement the MCMC gave the following fit:

Gain = 3.15e+06 cts/m 
Pole = 428 Hz 
Delay = 5.64e-05 s
Spring Freq = -3.03 Hz
Q = 349

This is an apparent reduction in the DARM optical gain  as reported on March 20th.

From March 20th, 
The DARM optical gain goes down,
the DARM pole increased,
the spring frequency went from -4 Hz to -3 Hz.

The only thing about the DARM plant which has changed is the ITM ring heaters temps going down, as far as I know.
Non-image files attached to this report