Nutsinee, Stefan

We designed a squeezing monitor BLRMS bank into H1:OAF-RANGE_RBP_7 (band-pass) and H1:OAF-RANGE_RLP_7 (low pass or the squared signal).

Band pass: ellip("BandPass",8,0.1,80,628,900) zpk([0;0;0],[100;100;100],0.000001,"n") (figure 1) (This focuses on the clean region between 628Hz and 900Hz, carefully placing the notches of the elliptic bandstop on the violin modes.

RMS low-pass: 0.02Hz pole

To our surprise, we notices very frequent (~all 5 secs or so) transients that actually dominate the background shot noise level by maybe a dB or so, figure(2).

We could use detchar help to track those things down.

The measurement was done with the squeezer on, but the glitches persist without squeezer.

On Tuesday, Corey and I went through the laborious task of checking and charging as needed the 50 accumulators on H1.

We found a dozen or so that could use a top up but just a few of those were quite low.  One needed a schrader valve replaced.

After this and bleeding air from the resistors, we set the trip level of the reservoir.  WP 8099 closed.

This morning I spent some time moving offsets on SRC1 (AS72) to see if I could improve the alignment.  While doing this, I watched POP90 (to see that it went down, implying more 45 MHz build up in the SRC), and BLRMS around the 331 Hz and 1083 Hz calibration lines.  The POP90 went down, and POP18 went up by a small amount.  Also, the cal line at 331 Hz stayed pretty close to where it was in my reference.  The 1083 Hz line moves up and down a fair amount, but with my new SRC offsets seems to be at or above my reference at most times, while at other trial SRC offsets it seems to be at or below the reference at most times.  So, I think that the DARM cavity pole might have gone up a teeny bit.   My offsets were 0.2 in pitch and 1.0 in yaw.  I am leaving them out of the guardian, since we're going to do more SRC heating/alignment tests over the weekend, and this will need to be redone anyway.

After the SRC alignment was changed, Danny and I remeasured the SRCL FF, and implemented a new Feb28 filter in SRCLFF1. 

Then, I ran a pcal sweep, which is saved at /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Measurements/FullIFOSensingTFs/2019-02-28_H1_PCAL2DARM_TF_5t1100Hz_8min.xml

Reminder to self on how to run the new FF fitting scripts:

• Measurement templates are in /opt/rtcds/userapps/release/lsc/h1/scripts/feedforward/
• Need to use Craig's python environment, which includes both the DTT extraction as well as iirrational fitting tools.
  • source /opt/rtcds/userapps/release/cds/h1/scripts/setup_anaconda
  • source activate cragenv
• Turn off existing feedforward
  • Turn off the input, and any filters that are engaged.
• Do the 2 measurements, save them (ensure they are checked into svn first, then overwrite old files)
  • [MICH / SRCL]_to_DARM_excitation.xml
  • [MICH / SRCL]FF_to_DARM_excitation.xml
• Open the script in the subfolder ipython_notebooks
  • >> jupyter notebook SRCL2DARMfeedforward.ipynb
• Run the notebook, one cell at a time.
• Copy the zpk output to Foton, and try the filter out!

The peaks at 206Hz and 234Hz are gone. I guess the PBS did something good. The other two lines are still persistent. One at 177.7Hz got worse after I closed and reopened the beam diverter after a long lock (orange trace for ASQZ, cyan for SQZ). Compare to purple trace that I took right when I got in the control room. The line at 262Hz got worse after the beam diverter closed/opened but got better after sometime passed (dark purple). Maybe this suggests something mechanical? The next thing to do is to check the coherence with accelerometers.

Note that I kept the phase the same as last sqz measurement and I didn't optimized the nlg before I took this measurement (temperature setting was the same as last time).

FAMIS8246

BRS temps seem to be drifting up.

TITLE: 02/28 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Commissioning
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    Wind: 3mph Gusts, 1mph 5min avg
    Primary useism: 0.05 μm/s
    Secondary useism: 0.34 μm/s
QUICK SUMMARY: Roads are VERY icy, please be safe driving in. Bubba has plowed around the corner station and the IFO stayed locked. Riding a 7+ hour lock right now.

Bubba was out clearing snow just outside the LVEA with the big front loader.  The IFO saw this, and the range was a little low for a little while, but stayed locked just fine (currrent lock more than 7 hours long so far).  Good to know that snow clearing doesn't necessarily mean we'll lose lock.

During todays lock, presumably with the spot position change, ETMY mode 1 (510.715 Hz) rang up with its usual parameters. I have changed the phase of the damping filters, replacing FM4 (+60degrees bad) with FM8 (+60degrees) and this seems to have done the trick. I put the new parameters in lscparams. If this works long term then we should probably just get rid of the bad phase filter.

I also noticed that over the long lock today ETMX mode9 (516.78 Hz) damping got turned off, and it very slowly rang up. This one is a bit of a trap since mode9 isn't displayed on the violin overview screen (only the first 8), note to self: move this to one of the unused lower number filters.

We got a few noise budget injections done in this lock before we lost lock.  We will post a more complete noise budget once we have some more of the excitations done, a partial noise budget for the ASC noise contributions to DARM are attached. 

The other interesting thing that we found was that MICH is only about a factor of 3 below DARM from 60-80Hz.  

After we lost lock we needed to redo initial alignment, this might require realignment on ISCT1 since Jenne updated the initial alignment references for our new spot positions. 47168

Craig, Stefan, Danny

• While updating the MICHFF we noticed that there was a drop in coherence between MICH and DARM that couldn't be accounted for by any notch filters in the MICH loop
• Discovered a notch/resonance feature in the MICH OLTF between 17 and 18 Hz.
• Using /opt/rtcds/userapps/release/lsc/h1/scripts/MICH_OLTF_fit.ipynb we use IIRational which gives us the following zpk fit of the notch/resonance with frequencies in rad/s:

  • zpk(
    [
    -4.727413e-02+i*1.115585e+02; 
    -4.727413e-02-i*1.115585e+02; 
    ],
    [
    -2.325583e-02+i*1.118566e+02; 
    -2.325583e-02-i*1.118566e+02; 
    ],
    4.596248e-01
    )

• We will be adding a filter to the MICH loop to mitigate its effects.

FAMIS11206

SR3 is a known problem, but besides that ETMX P is nearing 10urad.