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Entry  Tue Sep 7 18:00:54 2021, Tega, Summary, Calibration, System Identification via line injection raw_timeseries.pdfdemod_signals.pdfcal_noise_asd.pdf
    Reply  Tue Sep 21 11:09:34 2021, Anchal, Summary, CDS, XARM YARM UGF Servo and Oscillators added 
       Reply  Wed Sep 22 12:40:04 2021, Anchal, Summary, CDS, XARM YARM UGF Servo and Oscillators shifted to OAF 
    Reply  Tue Sep 21 11:13:01 2021, Paco, Summary, Calibration, XARM calibration noise XARM_signal_asd.pdfXARM_demod_timeseries.pdfXARM_demod_asds.pdfXARM_cal_0921_timeseries.pdf
       Reply  Wed Sep 22 11:43:04 2021, rana, Summary, Calibration, XARM calibration noise 
          Reply  Tue Sep 28 16:31:52 2021, Paco, Summary, Calibration, XARM OLTF (calibration) at 55.511 Hz OLTF_Calibration_Scheme.jpgXARM_POX_Lock_Model_TF.pdfXARM_OLTF_Total_Model.pdfXARM_OLTF_55p511_Hz_timeseries.pdfGmag_55p511_Hz_ASD.pdf
             Reply  Thu Sep 30 18:04:31 2021, Paco, Summary, Calibration, XARM OLTF (calibration) with three lines XARM_OLTF_Model_and_Meas.pdfGmag_ASD_nb_withTRX.pdf
Message ID: 16369     Entry time: Thu Sep 30 18:04:31 2021     In reply to: 16363
Author: Paco 
Type: Summary 
Category: Calibration 
Subject: XARM OLTF (calibration) with three lines 

[anchal, paco]

We repeated the same procedure as before, but with 3 different lines at 55.511, 154.11, and 1071.11 Hz. We overlay the OLTF magnitudes and phases with our latest model (which we have updated with Koji's help) and include the rms uncertainties as errorbars in Attachment #1.

We also plot the noise ASDs of calibrated OLTF magnitudes at the line frequencies in Attachment #2. These curves are created by calculating power spectral density of timeseries of OLTF values at the line frequencies generated by demodulated XARM_IN and ETMX_LSC_OUT signals. We have overlayed the TRX noise spectrum here as an attempt to see if we can budget the noise measured in values of G to the fluctuation in optical gain due to changing power in the arms. We multiplied the the transmission ASD with the value of OLTF at those frequencies as the transfger function from normalized optical gain to the total transfer function value.

It is weird that the fluctuations in transmission power at 1 mHz always crosses the total noise in the OLTF value in all calibration lines. This could be an artificat of our data analysis though.

Even if the contribution of the fluctuating power is correct, there is remaining excess noise in the OLTF to be budgeted.

Attachment 1: XARM_OLTF_Model_and_Meas.pdf  40 kB  Uploaded Fri Oct 1 15:49:00 2021  | Hide | Hide all
XARM_OLTF_Model_and_Meas.pdf XARM_OLTF_Model_and_Meas.pdf
Attachment 2: Gmag_ASD_nb_withTRX.pdf  42 kB  Uploaded Fri Oct 1 15:52:31 2021  | Hide | Hide all
Gmag_ASD_nb_withTRX.pdf Gmag_ASD_nb_withTRX.pdf Gmag_ASD_nb_withTRX.pdf
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