J.Kissel, T.Mistry
Here are some 'Money Plots' for the NCAL Sweep that was taken on the 04-Dec-2019.
Figure 1 :: A move/animation of the sweep as seen in the control room DARM spectrum.
Figure 2 :: ASD of the DARM plot with labelled frequencies from 5 to 600Hz.
Figure 3 :: ASD of the DARM plot with tagged frequencies from 5 to 40Hz.
Figure 4 :: Spectrogram of the NCAL Sweep from 0 to 50 Hz.
Figure 5 :: Spectrogram of the NCAL Sweep from 0 to 1000 Hz.
Figure 6 :: IWAVE line tracking of the Optical encoder as the NCAL changes velocity.
All the figures are also available in DCC G1902340.
An interesting feature to see is that when the NCAL is settling to a new frequency, making what appears to be sidebands. This is due to the NCAL slightly overshooting the requested frequency before settling down to the desired velocity. This is an expected results as a result of the NCAL motor behaviour due to the internal motor parameters. It is possible to configure the motor parameters to reduce the overshoot however, the current implementation is a trade off between time taken to accelerate to a given frequency and the stresses on the motor.
Below is a timeline of the NCAL sweep. The values in red are not visable due to the lack of SNR at low frequency. A longer intergration time would be required to see the lines below 5Hz.
NOTE: to create a movie and upload it to the alog I did the following onn the LHO control room machines:
- In the main menu of the PC navigate to Multimedia>RecordMyDesktop
- Press the select window button and click on the DTT window (a black outline will appear to confirm this window is selected as well as the preview in RecordMyDesktop will show the highlighted window).
- Press Record and then started the DTT file
- Once the DTT file was done, I used CRTL+ALT+S to stop the recording.
- A file called out.ogv is made in my home folder.
- Converted out.ogv to a .mpy using:
ffmpeg -i out.ogv MyFile.mp4
- Uploaded .mp4 file to the alog in the same way one would attach an image (Using 'UPLOAD / MANAGE FILES')
J. Kissel These Dec 4th 2019 measurements were run from 1259535305 to 1259539158 (Dec 04 2019 22:54:47 UTC to Dec 04 2019 23:59:00 UTC). Any and all O3 C01 systematic error estimates for any observation-ready hour are now available on the CIT cluster in a standard location that the GW data analysis teams use (they weren?t back in Apr 2020 when I produced the plot on page 32 of the Review of the First Results, G2000532). For Hanford, they live in https://ldas-jobs.ligo.caltech.edu/~cal/uncertainty/O3C01/H1/ So we want the file that?s the nearest in time to the time frame of 1259535305 to 1259539158 (which was *out* of observation ready time). During the whole time the detector was out of observation ready mode, the IFO was locked, happy, and stable as one can see from the summary pages, https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/day/20191204/ Also from the summary pages, one can see that the time-dependent correction factors remained the same before vs. after the observation ready stretch, https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/day/20191204/cal/time_varying_factors/ We went back in to observation ready mode right *after* the NCAL injections, so actually the nearest time *after* the injections will be the best. That's the file https://ldas-jobs.ligo.caltech.edu/~cal/uncertainty/O3C01/H1/2020-06-12_O3_LHO_GPSTime_1259540100_C01_RelativeResponseUncertainty_FinalResults.txt at 1259540100, or Dec 05 2019 00:14:42 UTC, 942 seconds later, or 16 minutes later. (Ignore the date at the beginning of the file name: that?s a reflection of when the file was created, not a reflection of the time for which the systematic error budget applies. That?s indicated by the GPS time in the file name). This shall be the h(f) systematic error we use to compare against in the forthcoming NCAL paper.
J. Kissel The spot positions for this measurement, determined by the P2L and Y2L decoupling gains which were 4.3 and 3.6 respectively for this entire lock stretch on Dec 04 2019, are 15.7 mm in -Vertical, and 13.2 mm in +Transverse. See further discussion of how these numbers are determined in LHO aLOG 58023 (i.e the NCAL's swan song on Sep 03 2020, which had the exact same spot positions).