Dripta and I went to EY with PS4 to do a PCAL ES measurement. We followed the T1500062-v21 Procedure but there were changes to the scripts we were using to do the analysis for this measurement.
Obligitory before beam spot.
python3 generate_measurement_data.py --WS PS4 --date 2026-04-02
Reading in config file from python file in scripts
../../../Common/O4PSparams.yaml
PS4 rho, kappa, u_rel on 2026-04-02 corrected to ES temperature 299.9 K :
-4.7013350503199405 -0.0002694340454223 0.0007506545774987483
Copying the scripts into tD directory...
Connected to h1daqnds1
martel run
reading data at start_time: 1459616830
reading data at start_time: 1459617300
reading data at start_time: 1459617635
reading data at start_time: 1459618001
reading data at start_time: 1459618370
reading data at start_time: 1459618700
reading data at start_time: 1459619030
reading data at start_time: 1459619580
reading data at start_time: 1459619930
Ratios: -0.5341166097396405 -0.5439653195648569
writing nds2 data to files
finishing writing
Background Values:
bg1 = 18.656956; Background of TX when WS is at TX
bg2 = 5.029697; Background of WS when WS is at TX
bg3 = 18.678297; Background of TX when WS is at RX
bg4 = 5.152238; Background of WS when WS is at RX
bg5 = 18.675415; Background of TX
bg6 = -0.527308; Background of RX
The uncertainty reported below are Relative Standard Deviation in percent
Intermediate Ratios
RatioWS_TX_it = -0.534117;
RatioWS_TX_ot = -0.543965;
RatioWS_TX_ir = -0.526729;
RatioWS_TX_or = -0.535441;
RatioWS_TX_it_unc = 0.057495;
RatioWS_TX_ot_unc = 0.055038;
RatioWS_TX_ir_unc = 0.052784;
RatioWS_TX_or_unc = 0.054928;
Optical Efficiency
OE_Inner_beam = 0.986428;
OE_Outer_beam = 0.984304;
Weighted_Optical_Efficiency = 0.985366;
OE_Inner_beam_unc = 0.042212;
OE_Outer_beam_unc = 0.043766;
Weighted_Optical_Efficiency_unc = 0.060806;
Martel Voltage fit:
Gradient = 1637.917034;
Intercept = 0.063908;
Power Imbalance = 0.981895;
Endstation Power sensors to WS ratios::
Ratio_WS_TX = -0.927573;
Ratio_WS_RX = -1.384310;
Ratio_WS_TX_unc = 0.046237;
Ratio_WS_RX_unc = 0.042014;
=============================================================
============= Values for Force Coefficients =================
=============================================================
Key Pcal Values :
GS = -5.135100; Gold Standard Value in (V/W)
WS = -4.701335; Working Standard Value
costheta = 0.988362; Angle of incidence
c = 299792458.000000; Speed of Light
End Station Values :
TXWS = -0.927573; Tx to WS Rel responsivity (V/V)
sigma_TXWS = 0.000429; Uncertainity of Tx to WS Rel responsivity (V/V)
RXWS = -1.384310; Rx to WS Rel responsivity (V/V)
sigma_RXWS = 0.000582; Uncertainity of Rx to WS Rel responsivity (V/V)
e = 0.985366; Optical Efficiency
sigma_e = 0.000599; Uncertainity in Optical Efficiency
Martel Voltage fit :
Martel_gradient = 1637.917034; Martel to output channel (C/V)
Martel_intercept = 0.063908; Intercept of fit of Martel to output (C/V)
Power Loss Apportion :
beta = 0.998844; Ratio between input and output (Beta)
E_T = 0.992082; TX Optical efficiency
sigma_E_T = 0.000302; Uncertainity in TX Optical efficiency
E_R = 0.993230; RX Optical Efficiency
sigma_E_R = 0.000302; Uncertainity in RX Optical efficiency
Force Coefficients :
FC_TxPD = 9.158224e-13; TxPD Force Coefficient
FC_RxPD = 6.227715e-13; RxPD Force Coefficient
sigma_FC_TxPD = 4.284257e-24; TxPD Force Coefficient
sigma_FC_RxPD = 2.800786e-24; RxPD Force Coefficient
data written ... to /ligo/gitcommon/Calibration/pcal/O4/ES/measurements/LHO_EndY/tD20260407
Martel_Voltage_test.png
WS_at_RX.png
WS_at_TX.png
WS_at_RX_BOTH_BEAMS.png
Final Report is here: LHO_EndY_PD_ReportV6.pdf
Final beamspot .
