• Interferometer_Characterization
• PRMI_Noise_Budget

PRMI Noise budget

• Noise curves to be included
  • Shot noise
  • DAC noise
  • Alignment noise
  • Up conversion noise
  • what else ?

Measurements

• 7/Mar/2012 by KI

Sensor in use

• AS55_Q for MIHC

  • Gain of whitening filter = 30 dB

  • Demodulation phase = 17.6 deg

  
  

• REFL33_I for PRCL

  • Gain of whitening filter = 42 dB

  • Demodulation phase = -38.050 deg

• LO = 11065910 Hz by a Marconi

DC light

• port name	DC power [mW]
  AS (before the attenuation)	0.02 mW
  AS55	? mW
  REFL (before the attenuation)	644 mW
  REFL11	? mW
  REFL33	? mW
  REFL55	? mW
  REFL165	? mW

Sidebands

• The values noted here were estimated from the OSAs at the AS and REFL ports.

Optical gains

• MICH sensor parameters
  description	values	notes
  Estimated Optical gain	uW/m
  Measured pk-pk Michelson error signal	1000 counts	Michelson was freely swinging
  Raw optical gain	Hm = 1.034768e+11 [counts/m]	= 4 * pi / lambda * (pk value of the error signal)
  Conversion loss of mixer	6.5 dB	from the spec sheet of JMS-1H
  ADC conversion	1638.4 counts / V	16 bit, +/-20 V
  Trans impedance at 55 MHz	556.3 Ohm	AS55 characterization
  Responsibity of diodes	0.8 [A/W]	from the spec sheet of CS3102
  Attenuation in the AS path

• PRCL sensor parameters
  description	values	notes
  Estimated Optical gain
  Measured pk-pk Michelson error signal	1000 counts	Michelson was freely swinging
  Raw optical gain	Hp = 5.934718e+10 [counts/m]	= 4 * pi / lambda * (pk value of the error signal)
  Conversion loss of mixer	6.5 dB	from the spec sheet of JMS-1H
  ADC conversion	1638.4 counts / V	16 bit, +/-20 V
  Trans impedance at 55 MHz	556.3 Ohm	AS55 characterization
  Responsibity of diodes	0.8 [A/W]	from the spec sheet of CS3102
  Attenuation in the AS path

Servo filters

• 

  MICH servo
  description	values	notes
  UGF	100 Hz
  Filters activated	FM5(10:1000)
  Gain	G = -5
  Feedback	-0.9905 * ITMX + 1 * ITMY	via the output matrix
  Dewhitening filter	On	in both ITMX and ITMY
  Limiter	off
  Time delay	480 usec	without considering the effects from analog circuits and downsampling filters

  
  
  

  PRCL servo
  description	values	notes
  UGF	100 Hz
  Filters activated	FM5(10:1000)
  Gain	G = - 0.04
  Power Normalization	REFL33/POYDC/0.25	via the normalization matrix
  Feedback	PRM
  Dewhitening filter	On	PRM
  Limiter	off
  Time delay	480 usec	without considering the effects from analog circuits and downsampling filters

• Note: the following values are assumed for fitting the data

•      ITMX  = 4.913e-09 / f2   [m/counts]
       ITMY  = 4.832e-09 / f2   [m/counts]
       PRM   = 2.022e-08 / f2  [m/counts]

• For more details see summary of the actuators

RAM effects

• Is something going on ?