Reports until 10:07, Monday 21 November 2016
H1 CAL
jeffrey.kissel@LIGO.ORG - posted 10:07, Monday 21 November 2016 (31667)
Calibration Update Process Interrupted by EQ
J. Kissel, K. Izumi, D. Tuyenbayev 

We were just about to use a new sweep I took (with data attached) to update the front-end portion of the low-latency calibration pipeline during the ~30 hour lock stretch, but we were rudely interrupted by a 6.4 [mag] EQ in Argentina. Thus we have not yet updated the calibration. We will resume tomorrow morning when we are on site and can get a before and after change set of measurements.

Things on the plate to update:
(1) DC actuation strength, based on results from frequency-dependent sweeps of each actuation stage and the long-duration, single frequency measurements taken in the first few weeks of ER10. We expect the TST and UIM stage to receive updates on the level of a few percent. We expect this will increase the BNS range a bit.
(2) The frequency dependence of all stages of the actuator. This is to account for optical lever damping, and newly included UIM violin mode resonances. We do not expect this to affect the BNS range.
(3) Small adjustments to the inverse sensing function to get updated values for the optical gain (will likely be ~3% higher). We expect this to decrease the BNS range a bit.
(4) EPICs records that store the DARM loop model at calibration line frequencies to match the reference measurement times.

Unfortunately, its only after we make these updates will we be able to trust any of the time-dependent tracking system.

All this being said, the current sensing function sweep (retaken today) sweep shows that the PCAL is discrepant with DELTAL external by 5% (though this changes with time as the TST actuation strength, optical gain, SRC detuning, and cavity pole change). However, we think we can reduce this systematic offset by making the above updates. 

The strange thing, is that the fit RSE cavity pole and SRC detuned spring freq are statistically different than what has been measured to-date. I'm worried this has to do with Shiela's finalizing the alignment configuration to get back onto REFL WFS (see LHO aLOG 31653).


                                 [Units]  value(95% c.i.)

Meas Date                 2016            Nov 20        
IFO Input Power                  [W]      29.1          
SRC1 Loop Status                          ON            

Optical Gain              x 1e6  [ct/m]   1.15 (0.002)
DARM/RSE Cav. Pole Freq.         [Hz]     353.5(6.0)
Detuned SRC Optical Spring Freq. [Hz]     7.02 (0.3)   
Optical Spring Q-Factor (1/Q)    []       0.04 (0.01)  
Residual Time Delay              [us]     2.4  (5.4)   
 
aLOG                                      this aLOG 

Details:

CalSVN repo root: [~] = /ligo/svncommon/CalSVN/aligocalibration/

Data lives here:
[~]/trunk/Runs/ER10/H1/Measurements/
DARMOLGTFs/2016-11-20_H1_DARM_OLGTF_4to1200Hz_fasttemplate.xml
PCAL/2016-11-20_H1_PCAL2DARMTF_4to1200Hz_fasttemplate.xml


Analysis produced by running:
[~]/trunk/Runs/ER10/H1/Scripts/PCAL/fitDataToC_20161116.m          Revision: 3815
on each of the measurement config files listed below.

Model Config Files:
[~]/trunk/Runs/ER10/Common/params/IFOindepParams.conf              Revision: 3776
[~]/trunk/Runs/ER10/H1/params/H1params.conf                        Revision: 3811
[~]/trunk/Runs/ER10/H1/params/2016-11-12/H1params_2016-11-12.conf  Revision: 3800

Measurement Config Files:
[~]/trunk/Runs/ER10/H1/params/2016-11-20/measurements_2016-11-20_sensing.conf   Revision: 3821
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Non-image files attached to this report