ifo.yaml

# 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
#
# Updated numbers March 2018: LIGO-T1800044

Infrastructure:
  Length: 3995                    # m
  Temp: 290                       # K
  ResidualGas:
    pressure: 4.0e-7              # Pa
    mass: 3.35e-27                # kg; Mass of H_2 (ref. 10)
    polarizability: 7.8e-31       # m^3

TCS:
  # The presumably dominant effect of a thermal lens in the ITMs is an increased
  # mode mismatch into the SRC, and thus an increased effective loss of the SRC.
  # The increase is estimated by calculating the round-trip loss S in the SRC as
  # 1-S = |<Psi|exp(i*phi)|Psi>|^2, where
  # |Psi> is the beam hitting the ITM and
  # phi = P_coat*phi_coat + P_subs*phi_subs
  # with phi_coat & phi_subs the specific lensing profiles
  # and P_coat & P_subst the power absorbed in coating and substrate
  #
  # This expression can be expanded to 2nd order and is given by
  # S= s_cc P_coat^2 + 2*s_cs*P_coat*P_subst + s_ss*P_subst^2
  # s_cc, s_cs and s_ss were calculated analytically by Phil Willems (4/2007)
  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 equivalent 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)