Skip to content

GitLab

Commit a6c3c1c8 authored by Kevin Kuns's avatar Kevin Kuns
Browse files
Options

Update Cosmic Explorer interferometers 

* update the Cosmic Explorer noise budgets to those shown in arXiv:2012.03608
* remove CE2 and add CE2silica and CE2silicon
parent 52cfa009
Pipeline #176552 passed with stages
        in 2 minutes and 27 seconds
        Hide whitespace changes
        Inline Side-by-side
        Showing with 926 additions and 136 deletions
        IFO.md
        View file @ a6c3c1c8
        ......@@ -40,9 +40,17 @@ Ranges in "Mpc" are for binary neutron stars (BNS) using the
        ![CE1](https://gwinc.docs.ligo.org/pygwinc/ifo/CE1.png)
        ## Cosmic Explorer 2
        ## Cosmic Explorer 2 (Silica)
        * [ifo.yaml](gwinc/ifo/CE2/ifo.yaml)
        * [CE2.h5](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2.h5)
        * [ifo.yaml](gwinc/ifo/CE2silica/ifo.yaml)
        * [CE2silica.h5](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silica.h5)
        ![CE2](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2.png)
        ![CE2 (Silica)](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silica.png)
        ## Cosmic Explorer 2 (Silicon)
        * [ifo.yaml](gwinc/ifo/CE2silicon/ifo.yaml)
        * [CE2silicon.h5](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silicon.h5)
        ![CE2 (Silicon)](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silicon.png)
        README.md
        View file @ a6c3c1c8
        ......@@ -32,7 +32,8 @@ and future GW detectors (`gwinc.ifo`):
        * [A+](https://gwinc.docs.ligo.org/pygwinc/ifo/Aplus.png)
        * [Voyager](https://gwinc.docs.ligo.org/pygwinc/ifo/Voyager.png)
        * [Cosmic Explorer 1](https://gwinc.docs.ligo.org/pygwinc/ifo/CE1.png)
        * [Cosmic Explorer 2](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2.png)
        * [Cosmic Explorer 2 (Silica)](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silica.png)
        * [Cosmic Explorer 2 (Silicon)](https://gwinc.docs.ligo.org/pygwinc/ifo/CE2silicon.png)
        See [IFO.md](IFO.md) for the latest CI-generated plots and hdf5 cached
        data.
        ......
        gwinc/ifo/CE1/__init__.py
        View file @ a6c3c1c8
        ......@@ -69,7 +69,6 @@ class Substrate(nb.Budget):
        style = dict(
        label='Substrate Thermal',
        color='#fb7d07',
        linestyle='--',
        )
        noises = [
        ......@@ -78,6 +77,9 @@ class Substrate(nb.Budget):
        ]
        ExcessGas.style['linestyle'] = '-'
        class CE1(nb.Budget):
        name = 'Cosmic Explorer 1'
        ......
        gwinc/ifo/CE1/ifo.yaml
        View file @ a6c3c1c8
        # GWINC CE1 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
        ......@@ -26,8 +20,7 @@
        # 12. Gretarsson & Harry, Gretarsson thesis
        # 13. Fejer
        # 14. Braginsky
        #
        # Updated numbers March 2018: LIGO-T1800044
        Infrastructure:
        Length: 40000 # m; whoa
        ......@@ -35,9 +28,12 @@ Infrastructure:
        ResidualGas:
        pressure: 4.0e-7 # Pa
        mass: 3.35e-27 # kg; Mass of H_2 (ref. 10)
        polarizability: 7.8e-31 # m^3
        polarizability: 0.81e-30 # m^3 (H_2, DOI: 10.1116/1.1479360)
        BuildingRadius: 10 # m
        TCS:
        ## Parameter describing thermal lensing
        # 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
        ......@@ -66,6 +62,7 @@ TCS:
        # 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: 5 # Hz; freq where 'flat' noise rolls off
        ......@@ -76,134 +73,129 @@ Seismic:
        Rho: 1.8e3 # kg/m^3; density of the ground nearby
        Beta: 0.8 # quiet times beta: 0.35-0.60
        # noisy times beta: 0.15-1.4
        Omicron: 1 # Feedforward cancellation factor
        Omicron: 2 # Feedforward cancellation factor
        TestMassHeight: 1.5 # m
        pWaveSpeed: 600 # m/s
        sWaveSpeed: 300 # m/s
        RayleighWaveSpeed: 250 # m/s
        pWaveLevel: 50 # Multiple of the Peterson NLNM amplitude
        sWaveLevel: 40 # Multiple of the Peterson NLNM amplitude
        PlatformMotion: 'BSC'
        PlatformMotion: 'intermediate'
        Atmospheric:
        AirPressure: 101325 # Pa
        AirDensity: 1.225 # kg/m**3
        AdiabaticIndex: 1.4
        SoundSpeed: 344 # m/s
        AirPressure: 101325 # Pa
        AirDensity: 1.225 # kg/m**3
        AirKinematicViscosity: 1.8e-5 # m**2/s
        AdiabaticIndex: 1.4 #
        SoundSpeed: 344 # m/s
        WindSpeed: 10 # m/s; typical value
        Temperature: 300 # K
        TempStructConst: 0.2 # K**2/m**(2/3);
        TempStructExp: 0.667 #
        TurbOuterScale: 100 # m
        # TurbEnergyDissRate: 0.01 # m**2/s**3
        KolmEnergy1m: 1 # Kolmogorov energy spectrum at 1/m [m**2/s**2]
        Suspension:
        Type: 'Quad'
        FiberType: 'Tapered'
        BreakStress: 750e6 # Pa; ref. K. Strain
        Temp: 290
        # VHCoupling:
        # theta: 1e-3 # vertical-horizontal x-coupling (computed in precompIFO)
        VHCoupling:
        theta: 3.1e-3 # vertical-horizontal x-coupling
        Silica:
        Rho : 2.2e3 # 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 : 7.2e10 # 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://www.ioffe.ru/SVA/NSM/Semicond/Si/index.html
        # all properties should be for T ~ 120 K
        Silicon:
        Rho: 2329 # Kg/m^3; density
        C: 300 # J/kg/K heat capacity
        K: 700 # W/m/K thermal conductivity
        Alpha: 1e-10 # 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: -2e-5 # (1/K) dlnE/dT T=120K
        Phi: 2e-9 # Nawrodt (2010) loss angle 1/Q
        Y: 155.8e9 # Pa Youngs Modulus
        Dissdepth: 1.5e-3 # 10x smaller surface loss depth (Nawrodt (2010))
        Fiber:
        Radius: 456e-6 # m
        # for tapered fibers
        # EndRadius is tuned to cancel thermo-elastic noise (delta_h in suspQuad)
        # EndLength is tuned to match bounce mode frequency
        EndRadius: 1.163e-3 # m
        EndLength: 45e-3 # m
        # 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: 316.8 # kg; current numbers May 2006 NAR
        # length adjusted for d = 10mm 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)
        Length: 1.18 # m
        - Mass: 320 # kg
        Length: 2 # m
        Dilution: .nan #
        K: .nan # N/m; vertical spring constant
        K: 1.57e4 # N/m; vertical spring constant
        WireRadius: .nan # m
        Blade: .nan # blade thickness
        Blade: 0.0045 # blade thickness
        WireMaterial: 'Silica'
        BladeMaterial: 'Silica'
        NWires: 4
        # Stage2
        - Mass: 316.8
        Length: 0.682
        Dilution: 106
        K: 41600
        WireRadius: 877e-6
        Blade: 0.011879
        - Mass: 320
        Length: 1.554
        Dilution: .nan
        K: 2.14e4
        WireRadius: 845e-6
        Blade: 13.3e-3
        NWires: 4
        WireMaterial: 'C70Steel'
        BladeMaterial: 'MaragingSteel'
        # Stage3
        - Mass: 174.4
        Length: 0.554
        Dilution: 80
        K: 31200
        WireRadius: 990e-6
        Blade: 0.013011
        - Mass: 299.2
        Length: 0.238
        Dilution: .nan
        K: 1.98e4
        WireRadius: 1.02e-3
        Blade: 15.7e-3
        NWires: 4
        WireMaterial: 'C70Steel'
        BladeMaterial: 'MaragingSteel'
        # Stage4
        - Mass: 176.8
        Length: 0.832
        Dilution: 87
        K: 27200
        WireRadius: 1471e-6
        Blade: 0.012162
        - Mass: 560.8
        Length: 0.208
        Dilution: .nan # 87
        K: 2.59e4
        WireRadius: 1.83e-3
        Blade: 16.8e-3
        NWires: 2
        WireMaterial: 'C70Steel'
        BladeMaterial: 'MaragingSteel'
        Ribbon:
        Thickness: 115e-6 # m
        Width: 1150e-6 # m
        # Suspension material properties
        Silica:
        Rho: 2200.0 # Kg/m^3
        C: 772.0 # 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
        Y: 72e9 # Pa; Youngs Modulus
        Dissdepth: 1.5e-2 # from G Harry e-mail to NAR 27April06
        Fiber:
        Radius: 424e-6 # m
        # for tapered fibers
        # EndRadius is tuned to cancel thermo-elastic noise (delta_h in suspQuad)
        # EndLength is tuned to match bounce mode frequency
        EndRadius: 1131e-6 # m; nominal 400um
        EndLength: 45e-3 # m; nominal 20mm
        C70Steel:
        Rho: 7800.0
        C: 486.0
        K: 49.0
        Alpha: 12e-6
        dlnEdT: -2.5e-4
        Phi: 2e-4
        Y: 212e9 # measured by MB for one set of wires
        ## Optic Material -------------------------------------------------------
        MaragingSteel:
        Rho: 7800.0
        C: 460.0
        K: 20.0
        Alpha: 11e-6
        dlnEdT: 0.0
        Phi: 1.0e-4
        Y: 187e9
        # consistent with measured blade spring constants NAR
        ## Optic Material
        Materials:
        MassRadius: 0.4 # m
        MassThickness: 0.286 # m
        MassRadius: 0.35 # m
        MassThickness: 0.378 # m
        ## Dielectric coating material parameters----------------------------------
        ## Dielectric coating material parameters
        Coating:
        ## high index material: tantala
        Yhighn: 124e9 # LMA (Granata at LVC) 2017 (was 140)
        ......@@ -213,7 +205,7 @@ Materials:
        Betahighn: 1.4e-5 # dn/dT, value Gretarrson (G070161)
        ThermalDiffusivityhighn: 33 # Fejer et al
        Indexhighn: 2.06539
        Phihighn: 9.0e-5 # tantala mechanical loss
        Phihighn: 7.0e-5 # tantala mechanical loss
        Phihighn_slope: 0.1
        ## low index material: silica
        ......@@ -224,14 +216,14 @@ Materials:
        Betalown: 8e-6 # dn/dT, (ref. 14)
        ThermalDiffusivitylown: 1.38 # Fejer et al
        Indexlown: 1.45
        Philown: 1.25e-5 # silica mechanical loss
        Philown: 2.3e-5 # silica mechanical loss
        Philown_slope: 0 # G1600641 and arXiv:1712.05701 suggest
        # slopes between 0 and 0.3, depending on
        # deposition method. Slawek's analysis in
        # 10.1103/PhysRevD.98.122001 assumes zero slope.
        ## Substrate Material parameters--------------------------------------------
        ## Substrate Material parameters
        Substrate:
        Temp: 295
        c2: 7.6e-12 # Coeff of freq depend. term for bulk mechanical loss, 7.15e-12 for Sup2
        ......@@ -244,53 +236,59 @@ Materials:
        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
        dndT: 9.6e-6 # 1/K; Heraeus Suprasil UVL
        ## Laser-------------------------------------------------------------------
        Laser:
        Wavelength: 1.064e-6 # m
        Power: 150 # W
        Power: 165 # W
        ## Optics------------------------------------------------------------------
        Optics:
        Type: 'SignalRecycled'
        Quadrature:
        dc: 1.5707963 # pi/2 # demod/detection/homodyne phase
        PhotoDetectorEfficiency: 0.96 # photo-detector quantum efficiency
        Loss: 20e-6 # average per mirror power loss
        BSLoss: 0.1e-3 # power loss near beamsplitter
        BSLoss: 0.5e-3 # power loss near beamsplitter
        coupling: 1.0 # mismatch btwn arms & SRC modes; used to
        # calculate an effective r_srm
        SubstrateAbsorption: 0.5e-4 # 1/m; bulk absorption coef (ref. 2)
        SubstrateAbsorption: 0.5e-4 # 1/m; 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:
        Transmittance: 0.014
        CoatingThicknessLown: 0.308
        CoatingThicknessCap: 0.5
        CoatingAbsorption: 0.5e-6
        ETM:
        Transmittance: 5e-6
        CoatingThicknessLown: 0.27
        CoatingThicknessCap: 0.5
        PRM:
        Transmittance: 0.03
        SRM:
        Transmittance: 0.02
        CavityLength: 55 # m, ITM to SRM distance
        Tunephase: 0.0 # SEC tuning
        CavityLength: 20 # m, ITM to SRM distance
        Curvature:
        ITM: 30000 # ROC of ITM
        ETM: 30000 # ROC of ETM
        Curvature: # ROC
        ITM: 34000
        ETM: 36000
        ## 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:
        # Define the squeezing you want:
        # None = ignore the squeezer settings
        # Freq Independent = nothing special (no filter cavities)
        # Freq Dependent = applies the specified filter cavities
        # Optimal = find the best squeeze angle, assuming no output filtering
        # OptimalOptimal = optimal squeeze angle, assuming optimal readout phase
        Type: 'Freq Dependent'
        AmplitudedB: 7 # SQZ amplitude [dB]
        InjectionLoss: 0.02 # power loss to sqz
        ......@@ -299,9 +297,9 @@ Squeezer:
        # Parameters for frequency dependent squeezing
        FilterCavity:
        fdetune: -4.99 # detuning [Hz] zz['x'][0][1]
        fdetune: -5.17 # detuning [Hz]
        L: 4000 # cavity length [m]
        Ti: 0.00167 # input mirror transmission [Power] zz['x'][0][2]
        Ti: 1.74e-3 # input mirror transmission [Power]
        Te: 5e-6 # end mirror transmission
        Lrt: 150e-6 # round-trip loss in the cavity
        Rot: 0 # phase rotation after cavity
        gwinc/ifo/CE2silica/__init__.py 0 → 100644
        View file @ a6c3c1c8
        from gwinc.ifo.noises import *
        from gwinc.ifo import PLOT_STYLE
        class QuantumVacuum(nb.Budget):
        """Quantum Vacuum
        """
        style = dict(
        label='Quantum Vacuum',
        color='#ad03de',
        )
        noises = [
        QuantumVacuumAS,
        QuantumVacuumArm,
        QuantumVacuumSEC,
        QuantumVacuumFilterCavity,
        QuantumVacuumInjection,
        QuantumVacuumReadout,
        QuantumVacuumQuadraturePhase,
        ]
        class Newtonian(nb.Budget):
        """Newtonian Gravity
        """
        name = 'Newtonian'
        style = dict(
        label='Newtonian',
        color='#15b01a',
        )
        noises = [
        NewtonianRayleigh,
        NewtonianBody,
        NewtonianInfrasound,
        ]
        class Coating(nb.Budget):
        """Coating Thermal
        """
        name = 'Coating'
        style = dict(
        label='Coating Thermal',
        color='#fe0002',
        )
        noises = [
        CoatingBrownian,
        CoatingThermoOptic,
        ]
        class Substrate(nb.Budget):
        """Substrate Thermal
        """
        name = 'Substrate'
        style = dict(
        label='Substrate Thermal',
        color='#fb7d07',
        )
        noises = [
        SubstrateBrownian,
        SubstrateThermoElastic,
        ]
        ExcessGas.style['linestyle'] = '-'
        class CE2silica(nb.Budget):
        name = 'Cosmic Explorer 2 (Silica)'
        noises = [
        QuantumVacuum,
        Seismic,
        Newtonian,
        SuspensionThermal,
        Coating,
        Substrate,
        ExcessGas,
        ]
        calibrations = [
        Strain,
        ]
        plot_style = PLOT_STYLE
        gwinc/ifo/CE2silica/ifo.yaml 0 → 100644
        View file @ a6c3c1c8
        # GWINC CE2 (Silica) interferometer parameters
        #
        # 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
        Infrastructure:
        Length: 40000 # m; whoa
        Temp: 293 # K
        ResidualGas:
        pressure: 4.0e-7 # Pa
        mass: 3.35e-27 # kg; Mass of H_2 (ref. 10)
        polarizability: 0.81e-30 # m^3 (H_2, DOI: 10.1116/1.1479360)
        BuildingRadius: 10 # m
        TCS:
        ## Parameter describing thermal lensing
        # 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 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: 5 # Hz; freq where 'flat' noise rolls off
        LowFrequencyLevel: 1e-9 # m/rtHz; seismic noise level below f_knee
        KneeFrequencyHorizontal: 4 # Hz; freq where 'flat' noise rolls off
        LowFrequencyLevelHorizontal: 1e-9 # m/rtHz; seismic noise level below f_knee
        Gamma: 0.8 # abruptness of change at f_knee
        Rho: 1.8e3 # kg/m^3; density of the ground nearby
        Beta: 0.8 # quiet times beta: 0.35-0.60
        # noisy times beta: 0.15-1.4
        Omicron: 10 # Feedforward cancellation factor
        TestMassHeight: 1.5 # m
        pWaveSpeed: 600 # m/s
        sWaveSpeed: 300 # m/s
        RayleighWaveSpeed: 250 # m/s
        pWaveLevel: 15 # Multiple of the Peterson NLNM amplitude
        sWaveLevel: 15 # Multiple of the Peterson NLNM amplitude
        PlatformMotion: '6D'
        Atmospheric:
        AirPressure: 101325 # Pa
        AirDensity: 1.225 # kg/m**3
        AirKinematicViscosity: 1.8e-5 # m**2/s
        AdiabaticIndex: 1.4 #
        SoundSpeed: 344 # m/s
        WindSpeed: 10 # m/s; typical value
        Temperature: 300 # K
        TempStructConst: 0.2 # K**2/m**(2/3);
        TempStructExp: 0.667 #
        TurbOuterScale: 100 # m