(Alexa, Sheila, Daniel)

Attached is a plot of the noise measurements taken from the error point of the EX PLL loop (i.e from IMON of the PFD). The overall PLL noise can be explained by the supressed auxiliary laser frequency noise at low frequency, and is dominated by the shot noise at high frequency. The plot also includes the BBPD dark noise which was subtracted out from the shot noise. There is also a first principles calculation of the shot noise, which is slightly different from the measured shot noise.

There is also a plot of the EX PDH noise measurements. The PDH error signal is a plot of the noise at the error signal of the PDH (i.e. at IMON of the demod). This graph includes the PDH dark noise and shot noise. Notably, the "shot noise" measurement is not pure shot noise. At low frequency there seems to be some fringe wrapping or acoustic noise. The graph also includes the noise from the PLL times the closed loop of the PLL (ie G/1+G). Clearly, some work needs to be done in explaining the noise at low frequency in th PDH loop.

Lastly, to validate the model, I have attached open loop tranfer functions of the EX PLL loop, EX PDH Loop, COMM PLL to VCO loop, and IMC Common Path (w/o COMM Handoff) from the model and data (collected over various alogs). Below are the settings used for the measurements. 

I am still working on getting the model to match the MC2 loop and the fast/slow path for the COMM handoff. Once I have validated this portion of the model, I will propagate the end station noise to the corner. I am also working on a documentation summarizing the model and all the measurements taken; this will eventually be posted on the dcc.

PLL Servo Board Settings
   Input 1 Pol: NEG
   Input 1 Gain: 0dB   
   Common Compensation: ON
   Generic Filter: ON
   Fast Option: ON
   Fast Gain: -8dB
   Boost 1: Off
   Rest: Off/Zero
PDH Servo Board Settings
   Input 1 Pol; POS
   Input 1 Gain: -11dB
   Common Compensation: ON
   Boost 1: On
   Rest: off/zero

COMM PLL to VCO Board
    Input enable: ON
    Polarity: OFF
    Gain: 31 dB
    Comm filter 1: ON
    Comm filter 2: ON
    Boost: OFF
    Filter: OFF
    VCO Compensation: ON
    Low pass: ON
    Daughter board: OFF

 IMC Servo Board
     Input 1 enable: ON
     Input 1 pol: POS
     Input 2 enable: OFF
     Input 2 pol: POS
     Input 2 gain: 16 dB
     Input 1 gain: 9 dB
     Common Compensation: ON
     Boost 1: ON
     Generic filter: ON
     Fast Gain: -6dB
     Fast enable: ON
     Fast Pol: POS
     Bypass: ON
 IMC-L
     FM1 (antiwhitening) ON
     Gain 1
 LSC-MC
     All Off
     Gain 1
 MC2_M3_ISCINF Filter
     FM6, FM7 On
     Gain 1
 MC2_M3_LOCK Filter
     FM3, FM9 ON
     Gain -300
 MC2_M2_LOCK Filter
     FM3, FM4, FM10 On
     Gain 0.1
 MC3_M1_LOCK Filter
     FM1, FM2 On
     Gain 1