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# GWINC aLIGO interferometer parameters
#
# parameters for quad pendulum suspension updated 3rd May 2006, NAR
# References:
# LIGO-T000012-00-D
# 	* Differentiate between silica and sapphire substrate absorption
# 	* Change ribbon suspension aspect ratio
# 	* Change pendulum frequency
# References:
# 1. Electro-Optic Handbook, Waynant & Ediger (McGraw-Hill: 1993)
# 2. LIGO/GEO data/experience
# 3. Suspension reference design, LIGO-T000012-00
# 4. Quartz Glass for Optics Data and Properties, Heraeus data sheet,
#    numbers for suprasil
# 5. Y.S. Touloukian (ed), Thermophysical Properties of Matter
#    (IFI/Plenum,1970)
# 6. Marvin J. Weber (ed) CRC Handbook of laser science and technology,
#    Vol 4, Pt 2
# 7. R.S. Krishnan et al.,Thermal Expansion of Crystals, Pergamon Press
# 8. P. Klocek, Handbook of infrared and optical materials, Marcel Decker,
#    1991
# 9. Rai Weiss, electronic log from 5/10/2006
# 10. Wikipedia online encyclopedia, 2006
# 11. D.K. Davies, The Generation and Dissipation of Static Charge on
# dielectrics in a Vacuum, page 29
# 12. Gretarsson & Harry, Gretarsson thesis
# 13. Fejer
# 14. Braginsky
#
#

Constants:
  # Temperature of the Vacuum
  Temp: 290 # K

Infrastructure:
  Length: 3995 # m
  ResidualGas:
    pressure: 4.0e-7 # Pa
    mass: 3.35e-27 # kg; Mass of H_2 (ref. 10)
    polarizability: 7.8e-31 # m^3

TCS:
  s_cc: 7.024 # Watt^-2
  s_cs: 7.321 # Watt^-2
  s_ss: 7.631 # Watt^-2
  # The hardest part to model is how efficient the TCS system is in
  # compensating this loss. Thus as a simple Ansatz we define the
  # TCS efficiency TCSeff as the reduction in effective power that produces
  # a phase distortion. E.g. TCSeff=0.99 means that the compensated distortion
  # of 1 Watt absorbed is eqivalent to the uncompensated distortion of 10mWatt.
  # The above formula thus becomes:
  # S= s_cc P_coat^2 + 2*s_cs*P_coat*P_subst + s_ss*P_subst^2 * (1-TCSeff)^2
  #
  # To avoid iterative calculation we define TCS.SCRloss = S as an input
  # and calculate TCSeff as an output.
  # TCS.SRCloss is incorporated as an additional loss in the SRC
  SRCloss: 0.00

Seismic:
  Site: 'LHO'                      # LHO or LLO (only used for Newtonian noise)
  KneeFrequency: 10                # Hz; freq where 'flat' noise rolls off
  LowFrequencyLevel: 1e-9          # m/rtHz; seismic noise level below f_knee
  Gamma: .8                        # abruptness of change at f_knee
  Rho: 1.8e3                       # kg/m^3; density of the ground nearby
  Beta: 0.5                        # quiet times beta: 0.35-0.60
  # noisy times beta: 0.15-1.4
  Omicron: 1                       # Feedforward cancellation factor

Suspension:
  # 0 for cylindrical suspension
  #Type: 'Quad'
  Type: 2
  # 0: round, 1: ribbons
  FiberType: 0
  BreakStress: 750e6            # Pa; ref. K. Strain
  Temp: 290
  VHCoupling:
    theta: 1e-3        # vertical-horizontal x-coupling

  Silica:
    Rho   : 2200           # Kg/m^3;
    C     : 772            # J/Kg/K;
    K     : 1.38           # W/m/kg;
    Alpha : 3.9e-7         # 1/K;
    dlnEdT: 1.52e-4        # (1/K), dlnE/dT
    Phi   : 4.1e-10        # from G Harry e-mail to NAR 27April06 dimensionless units
    Y     : 72e9           # Pa; Youngs Modulus
    Dissdepth: 1.5e-2      # from G Harry e-mail to NAR 27April06

  C70Steel:
    Rho: 7800
    C: 486
    K: 49
    Alpha: 12e-6
    dlnEdT: -2.5e-4
    Phi: 2e-4
    Y: 212e9        # measured by MB for one set of wires

  MaragingSteel:
    Rho: 7800
    C: 460
    K: 20
    Alpha: 11e-6
    dlnEdT: 0
    Phi: 1e-4
    Y: 187e9

  # ref ---- http://design.caltech.edu/Research/MEMS/siliconprop.html
  # all properties should be for T ~ 20 K
  Silicon:
    Rho: 2330                     # Kg/m^3;  density
    C: 772                        # J/kg/K   heat capacity
    K: 4980                       # W/m/K    thermal conductivity
    Alpha: 1e-9                   # 1/K      thermal expansion coeff
    # from Gysin, et. al. PRB (2004)  E(T): E0 - B*T*exp(-T0/T)
    # E0: 167.5e9 Pa   T0: 317 K   B: 15.8e6 Pa/K
    dlnEdT: 2.5e-10               # (1/K)    dlnE/dT  T=20K
    Phi: 2e-9                     # Nawrodt (2010)      loss angle  1/Q
    Y: 150e9                      # Pa       Youngs Modulus
    Dissdepth: 1.5e-3             # 10x smaller surface loss depth (Nawrodt (2010))

  # Note stage numbering: mirror is at beginning of stack, not end
  #
  # last stage length adjusted for d: 10mm and and d_bend = 4mm
  # (since 602mm is the CoM separation, and d_bend is accounted for
  # in suspQuad, so including it here would double count)
  Stage:
    # Stage1
    - Mass: 39.6                    # kg; current numbers May 2006 NAR
      Length: 0.59                  # m
      Dilution: .nan                #
      K: .nan                       # N/m; vertical spring constant
      WireRadius: .nan              # m
      Blade: .nan                   # blade thickness
      NWires: 4

    # Stage2
    - Mass: 39.6
      Length: 0.341
      Dilution: 106
      K: 5200
      WireRadius: 310e-6
      Blade: 4200e-6
      NWires: 4

    # Stage3
    - Mass: 21.8
      Length: 0.277
      Dilution: 80
      K: 3900
      WireRadius: 350e-6
      Blade: 4600e-6
      NWires: 4

    # Stage4
    - Mass: 22.1
      Length: 0.416
      Dilution: 87
      K: 3400
      WireRadius: 520e-6
      Blade: 4300e-6
      NWires: 2

  Ribbon:
    Thickness: 115e-6             # m
    Width: 1150e-6                # m

  Fiber:
    Radius: 205e-6                # m
    Blade: 4300e-6

## Optic Material -------------------------------------------------------
Materials:
  MassRadius: 0.17                # m; 
  MassThickness: 0.200            # m; Peter F 8/11/2005

  ## Dielectric coating material parameters----------------------------------
  Coating:
    ## high index material: tantala
    Yhighn: 140e9
    Sigmahighn: 0.23
    CVhighn: 2.1e6                # Crooks et al, Fejer et al
    Alphahighn: 3.6e-6            # 3.6e-6 Fejer et al, 5e-6 from Braginsky
    Betahighn: 1.4e-5             # dn/dT, value Gretarrson (G070161)
    ThermalDiffusivityhighn: 33   # Fejer et al
    Phihighn: 2.3e-4
    Indexhighn: 2.06539

    ## low index material: silica
    Ylown: 72e9
    Sigmalown: 0.17
    CVlown: 1.6412e6              # Crooks et al, Fejer et al
    Alphalown: 5.1e-7             # Fejer et al
    Betalown: 8e-6                # dn/dT,  (ref. 14)
    ThermalDiffusivitylown: 1.38  # Fejer et al
    Philown: 4.0e-5
    Indexlown: 1.45

  ## Substrate Material parameters--------------------------------------------
  Substrate:
    c2 : 7.6e-12                 # Coeff of freq depend. term for bulk mechanical loss, 7.15e-12 for Sup2
    MechanicalLossExponent: 0.77   # Exponent for freq dependence of silica loss, 0.822 for Sup2
    Alphas: 5.2e-12              # Surface loss limit (ref. 12)
    MirrorY: 7.27e10             # N/m^2; Youngs modulus (ref. 4)
    MirrorSigma: 0.167           # Kg/m^3; Poisson ratio (ref. 4)
    MassDensity: 2.2e3           # Kg/m^3; (ref. 4)
    MassAlpha: 3.9e-7            # 1/K; thermal expansion coeff. (ref. 4)
    MassCM: 739                  # J/Kg/K; specific heat (ref. 4)
    MassKappa: 1.38              # J/m/s/K; thermal conductivity (ref. 4)
    RefractiveIndex: 1.45        # mevans 25 Apr 2008

## Laser-------------------------------------------------------------------
Laser:
  Wavelength: 1.064e-6 # m
  Power: 125 # W

## Optics------------------------------------------------------------------
Optics:
  Type: 'SignalRecycled'
  PhotoDetectorEfficiency: 0.95    # photo-detector quantum efficiency
  Loss: 37.5e-6 # average per mirror power loss
  BSLoss: 0.5e-3                   # power loss near beamsplitter
  coupling: 1.0                     # mismatch btwn arms & SRC modes; used to

  #SubstrateAbsorption: 0.5e-4       # 1/m; bulk absorption coef (ref. 2)
  SubstrateAbsorption: 0.3e-4       # 1/m; 0.3 ppm/cm for Hereaus
  pcrit: 10                         # W; tolerable heating power (factor 1 ATC)
  Quadrature:
    dc: 1.5707963 # pi/2 # demod/detection/homodyne phase

  ITM:
    BeamRadius: 0.055 # m, 1/e^2 power radius
    Transmittance: 0.014
    CoatingThicknessLown: 0.308
    CoatingThicknessCap: 0.5
    CoatingAbsorption: 0.5e-6
    SubstrateAbsorption: 0.3e-4 # 1/m, 0.3 ppm/cm for Hereaus
  ETM:
    BeamRadius: 0.062 # m, 1/e^2 power radius
    Transmittance: 5e-6
    CoatingThicknessLown: 0.27
    CoatingThicknessCap: 0.5
  PRM:
    Transmittance: 0.03
  SRM:
    Transmittance: 0.20
    CavityLength: 55 # m, ITM to SRM distance
    Tunephase: 0.0 # SEC tuning

  Curvature: # ROC
    ITM: 1970
    ETM: 2192

## Squeezer Parameters------------------------------------------------------
# Define the squeezing you want:
#   None: ignore the squeezer settings
#   Freq Independent: nothing special (no filter cavties)
#   Freq Dependent = applies the specified filter cavites
#   Optimal = find the best squeeze angle, assuming no output filtering
#   OptimalOptimal = optimal squeeze angle, assuming optimal readout phase
Squeezer:
  Type: 'None'
  AmplitudedB: 10         # SQZ amplitude [dB]
  InjectionLoss: 0.05     # power loss to sqz
  SQZAngle: 0             # SQZ phase [radians]

  # Parameters for frequency dependent squeezing
  FilterCavity:
    fdetune: -14.5  # detuning [Hz]
    L: 100          # cavity length
    Ti: 0.12e-3     # input mirror trasmission [Power]
    Te: 0           # end mirror trasmission
    Lrt: 100e-6     # round-trip loss in the cavity
    Rot: 0          # phase rotation after cavity

## Variational Output Parameters--------------------------------------------
# Define the output filter cavity chain
#   None = ignore the output filter settings
#   Chain = apply filter cavity chain
#   Optimal = find the best readout phase
OutputFilter:
  Type: 'None'
  FilterCavity:
    fdetune: -30 # detuning [Hz]
    L: 4000      # cavity length
    Ti: 10e-3    # input mirror trasmission [Power]
    Te: 0        # end mirror trasmission
    Lrt: 100e-6  # round-trip loss in the cavity
    Rot: 0       # phase rotation after cavity