Date: April 24th, 2002

Attendees: Virginio, Luca, Erika, Matt, Hiro, Biplab (Caltech)

We discussed the relative importance and ways of inclusion of various noise sources and their coupling mechanisms in LIGO I model keeping the forthcoming Science runs in mind. These noises and coupling mechanisms are summarized below by Matt (additions/suggestions are welcome):

 ---- Noise Sources
 Seismic -> 1, 4d
 Frequency -> 4
 Digital Electronics -> 6
 Analog Electronics -> 5, 7
 Shot -> 5a
 Thermal -> 3
 Intensity -> 4

 ---- Couplings Mechanisms
 1) Stack -> 2a
 2) Pendulum -> 3
   a) suspension point
   b) actuators
   c) wire resonances
   d) test mass internal modes
 3) Mirror Position -> 4
 4) IFO
   a) simple optical asymmetries (R, T, L, ROC)
   b) non-horizontal geometry (wedge angles, earth's curvature)
   c) phase maps
   d) scattering
 5) Sensing Chain -> 6
   a) photo-detector
   b) whitening filters
   c) anti-aliasing
 6) Digital System -> 7
   a) ADC
   b) digital TF
   c) DAC
 7) Actuation Chain -> 2b
   a) anti-imaging
   b) dewhitening
   c) coil drivers

Any comments? write to bbhawal@ligo.caltech.edu