40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  PSL, Page 2 of 52  Not logged in ELOG logo
IDdown Date Author Type Category Subject Text Attachments
  2567   Tue Apr 14 12:24:16 2020 anchalDailyProgressNorth CavityNorth path's buggy nature Strikes Again!Today at sharp 8:30 am, perfectly fine
running experiment went bad again. The North
path became buggy again with strong low frequency
 NorthPathWentBuggy.pdf 
  2566   Mon Apr 13 16:52:30 2020 anchalDailyProgressBEATBeatnote measurements back on trackSince this morning atleast, I'm not
seeing the North Path unstability (see CTN:2565)
 CTN_Latest_BN_Spec.pdf 
  2565   Wed Mar 25 15:50:57 2020 anchalDailyProgressNorth CavityNorth path's buggy nature NOT solvedToday, magically almost, the North Path
was found to be locking nicely without the
noise. I was waiting for the beatnote to
 Screen_Shot_2020-03-25_at_3.48.24_PM.png 
  2564   Sun Mar 22 17:23:29 2020 anchalDailyProgressNorth CavityNorth path's buggy nature NOT solvedIt seems like this was never properly solved.
On Friday, the same problem was back again.
After trying relocking PMC and FSS on the
  
  2563   Thu Mar 19 15:34:41 2020 anchalDailyProgressNorth CavityNorth path's buggy nature solvedI found out that since the slow PID of
the FSS used Cavity reflection DC level,
it is important that this path remains rigid
 IMG_20200319_154013.jpg 
  2562   Wed Mar 18 12:51:22 2020 anchalDailyProgressBEATSuper beatnote measurement analysis resultsOn March 13th around 7:30 pm, I started
a super measurement of the beatnote spectrum
for over 2 days. The script superBNSpec.py
 CTN_Beatnote_SuperMeasurement_March13-16.pdf 
  2561   Tue Mar 17 18:03:22 2020 anchalDailyProgressISSAdded true OOL transmission PD for North PathToday, I added a new out-of-loop transmission
PD (Thorlabs PDA10CS) for the north path.
This will be helpful in future measurements
 IMG_20200317_180420.jpg 
  2560   Mon Mar 16 16:16:17 2020 anchalDailyProgressISSAdded true OOL transmission PD for South PathToday, I added a new out-of-loop transmission
PD (Thorlabs PDA10CS) for the south path.
This will be helpful in future measurements
  
  2559   Thu Mar 12 19:11:00 2020 shrutiDailyProgressISSRemoved half-wave plate in north path[Anchal, Shruti]

We realized that the half-wave
plates before the EOAMs probably had no real
  
  2558   Thu Mar 12 17:18:51 2020 ranaNotesFSSFSS Plant Model v2I think you have to protect this SimPlant
board from the HV from the FSS board ?

  
  2557   Thu Mar 12 16:21:49 2020 Ian MacMillanNotesFSSFSS Plant Model v2We added hooked up the plant and measured
the in loop transfer function (shown below).
The circuit locked in the system...
 TFSR785_10-03-2020_175129.pdfTFSR785_10-03-2020_175129.txt 
  2556   Thu Mar 12 11:06:35 2020 anchalDailyProgressBEATLowest ever beatnote spectrum today!Last night I switched off all the fans
in the lab and we have reached the lowest
ever recorded beatnote noise.
 CTN_Noise_Budget_March11-2020.pdf 
  2555   Wed Mar 11 16:43:55 2020 anchalDailyProgressISSComparison between Out of loop vs In loop RINI took spectrum of Out-of-loop (OOL) photodiode
and In-loop (IL) photodiodes with transmitted
light from the cavities when ISS is on in
 CTN_Trans_RIN_OOLvsIL.pdf 
  2554   Wed Mar 11 15:40:50 2020 Ian MacMillanNotesFSSFSS Plant Model v2I added a capacitor to c8 in the FSS plant
D2000020. This yielded the transfer function
shown below. This seems to have pushed the
 TFSR785_06-03-2020_135844_PZT.pdfTF_V1.zip 
  2553   Wed Mar 11 13:16:09 2020 anchalDailyProgressISSTransmitted Laser Relative Intensity Noise - Out of loopThese measurements take a long time as
I take a median over 500 single measurement
instances. I was able to increase gain later
  
  2552   Wed Mar 11 12:45:15 2020 ranaDailyProgressISSTransmitted Laser Relative Intensity Noise - Out of loopweird - why is the Gain different for in
loop and out of loop ?
  
  2551   Sat Mar 7 09:50:31 2020 anchalDailyProgressISSTransmitted Laser Relative Intensity Noise - Out of loopAttached are the latest transmitted RIN
measurements.


Measurement:


I
 CTN_Trans_RIN_measurement.pdf 
  2550   Tue Mar 3 17:13:04 2020 Ian MacMillanNotesFSSFSS Plant Model v2Anchal and I connected the circuit to the
EOM and PZT in a closed loop (LIGO-D040105).
We looked at the output as seen in the Oscilloscope
 image.pngPLT_Spectrum.pdf20200303_IanSimPlant.zipPLT_Spectrum.pdfPLT_TF.pdf 
  2549   Tue Mar 3 11:49:16 2020 anchalDailyProgressISSTransmitted Laser Relative Intensity NoiseAttached are the latest transmitted RIN
measurements.


Measurement:


These
 CTN_Trans_RIN_measurement.pdf 
  2548   Tue Mar 3 10:02:12 2020 anchalDailyProgressBEATLowest ever beatnote spectrum today!Measurement at 3 am in the morning today
has been the lowest ever recorded beatnote
noise. The lasers have been locked for more
 CTN_Noise_Budget_March03-2020.pdf 
  2547   Mon Mar 2 16:48:12 2020 anchalDailyProgressISSFollow-up, porbalem stopped happening, OLTF plot.The issue isn't visible right now.
I'm not sure what changed but with a
similar power level, I'm able to increase
 NISS_OLTF.pdf 
  2546   Sun Mar 1 16:34:31 2020 ranaDailyProgressISSInstalled New ISS on both paths using SR560s - PROBLEMdo
some step response and swept sine and post
  
  2545   Fri Feb 28 14:00:11 2020 anchalDailyProgressISSInstalled New ISS on both paths using SR560s - PROBLEMI'm currently struggling with a problem
in North ISS which I think needs to be documented
here. Here's the synopsis:
  
  2544   Sun Feb 23 18:19:32 2020 ranaDailyProgressISSInstalled New ISS on both paths using SR560s
too much gain peakin!


  
  2543   Fri Feb 21 16:22:04 2020 anchalDailyProgressBEATBeatnote noise lowered in low frequency region with ISSAfter installing the new ISS, the noise
is even lower in lower frequencies. Still
no change in the noisy peaks at 400 Hz and
 CTN_Noise_Budget_Effect_ISS_ON_New.pdf 
  2542   Thu Feb 20 17:42:23 2020 ranaDailyProgressISSInstalled New ISS on both paths using SR560sI've installed new ISS consisting of
one SR560 per path.


ISS SR560 Details:

 ISS_New_Analysis.pdf 
  2541   Tue Feb 18 15:42:46 2020 Ian MacMillanNotesFSSFSS Plant Model v2After switching out a bad opamp we have
clearer results.

Next steps: moving the real value
 PZT_TF_V1.pdfEOM_TF_V1.pdfTransfer_Functions_FSS.zip 
  2540   Mon Feb 17 16:08:23 2020 anchalDailyProgressBEATBeatnote noise lowered in low frequency region with ISSAfter installing the preliminary ISS, which
I'll change tomorrow as per Rana's
suggestions, we see some reduction in the
 CTN_Noise_Budget_Effect_ISS_ON.pdf 
  2539   Sat Feb 15 18:57:43 2020 ranaDailyProgressISSInstalled ISS on both paths using SR560syou don't need 6(!!) SR560s - just
1 for each loop:


AC coupled,
1st
  
  2538   Fri Feb 14 17:40:27 2020 anchalDailyProgressISSInstalled ISS on both paths using SR560sI've installed ISS on both paths using
3 SR560s each. Preliminary feedback is setup
to get a stable loop. More optimization with
 IMG_20200214_174127.jpgISS_Effect.pdf 
  2537   Fri Feb 14 16:46:47 2020 Ian MacMillanNotesFSSFSS Plant Model v2The PCB came in and I have assembled it.
The preliminary look at the transfer function
on the AG4395A shows that there is a
 TFAG4395A_14-02-2020_155048.pdfTFAG4395A_14-02-2020_165608.pdf 
  2535   Fri Feb 14 10:59:13 2020 anchalDailyProgressBEATBeatnote noise lowered in low frequency regionWith some of the changes done recently,
the beatnote noise has lowered in the low-frequency
region indicating reduction in scatter.
  
  2534   Thu Feb 13 18:06:00 2020 anchalDailyProgressNoiseBudgetAdding dark noise measurement of beatnote detector SN101I measured dark noise of the beatnote detector
reaching moku and its effect on measured
beatnote frequency noise.
 IMG_20200213_180742.jpgBNDetDarkNoise.pdf 
  2533   Thu Feb 13 18:00:30 2020 anchalDailyProgressscatterblocked NF1811 with hex beam dumpI have blocked the unused output port of
the beam splitter before our beatnote detector
with a hex beam dump at (13,
  
  2532   Thu Feb 13 16:35:32 2020 anchalDailyProgressBEATBN Detector was saturated. Reduced laser powers.I found that the beatnote detector was
actually saturating and the output was not
a good pure sinewave. I've reduced the
  
  2531   Thu Feb 13 15:27:18 2020 anchalDailyProgressBEATFurther iterated back and forth to optimized FSS Gains.I took beatnote measurements and spanned
gain values in the PMC to see if stability
issues in PMC loops can be affecting the
 FSS_Gain_Span.pdf 
  2530   Wed Feb 12 10:01:04 2020 anchalNotesBEATIncreased sampling rate to 125kSa/s; lowest noise in higher frequenciesI have increased the sampling rate of moku
to 125 kSa/s (fastest allowed) for the frequency-time
series acquisition. After reading matermost
  
  2529   Tue Feb 11 18:21:17 2020 anchalDailyProgressPMCCan't keep my mind of this; Why PMC Error signal has these oscillations?The PMC error signals have some weird broadened
oscillations in them:

 PMCErrSignalTimeSeries.pngPMC_Error_Signal_Analysis.pdf 
  2528   Mon Feb 10 17:41:25 2020 anchalDailyProgressscatterCleaned up table; Installed hex beam dumpsToday I cleaned up the table, removed Scott's
RFAM measurement setup and installed hex
beam dumps on the input rejection of faraday
  
  2527   Mon Feb 10 12:46:17 2020 Ian MacMillanNotesFSSFSS Plant Model v2Board Plant Circuit should come in on Feb.
18th. It is really taking its time. 
  
  2526   Mon Feb 10 11:07:33 2020 anchalDailyProgressBEATSpanned gain parameter space in PMCs and checked beatnoteI took beatnote measurements and spanned
gain values in the PMC to see if stability
issues in PMC loops can be affecting the
 PMC_Spanned_Beatnote_Variation.pdf 
  2525   Fri Feb 7 18:12:03 2020 anchalDailyProgressBEATSpanned gain parameter space in SFSS and checked beatnoteI took beatnote measurements and spanned
gain values (COM and FAST) on South side
to see the variation in beatnote with them.
 SFSS_Spanned_Beatnote_Variation.pdf 
  2524   Fri Feb 7 09:57:32 2020 anchalDailyProgressBEATSpanned gain parameter space in NFSS and checked beatnoteYesterday I took beatnote measurements
and spanned gain values (COM and FAST) to
see the variation in beatnote with them.
 NFSS_Spanned_Beatnote_Variation.pdf 
  2523   Thu Jan 30 10:55:22 2020 anchalNotesBEATLowest ever beatnote spectrum today.Today we have measured the lowest beatnote
spectrum till now. This happened because
I set the FSS gain values to lower than the
 CTN_Daily_BN_Spec.pdf 
  2522   Wed Jan 29 15:58:26 2020 anchalDailyProgressBEATBeanote Spectrum vs FSS Gain Values


Quote:


 Beatnote_vs_FSSGain.pdf 
  2521   Wed Jan 29 14:49:48 2020 anchalDailyProgressBEATBeanote Spectrum vs FSS Gain ValuesIn a discussion with Craig sometime back,
it was brought up what happens when I lower
the gains of the FSS loops. So today I did
 Beatnote_vs_FSSGain.pdf 
  2520   Tue Jan 28 13:27:25 2020 Ian MacMillanNotesFSSFSS Plant Model v2Added all documents to the LIGO document
for the FSS Plant Circuit LIGO-D2000020-v1.
The updated board and schematic are also
 LIGO-D2000020-v1.pdfBOARD_LIGO-D2000020-v1.pdfEagle_LIGO-D2000020-v1.zip 
  2519   Mon Jan 27 18:29:19 2020 anchalDailyProgressFSSFSS Diagnostics - RFPD RF Out SpectrumAfter the Notch improvement, I took 20
dB coupled outputs of the RF out ports of
the FSS RFPDs, SN009 (North) and SN010 (South),
 FSS_RFPD_RFOut_Spectrum.pdf 
  2518   Thu Jan 23 19:23:03 2020 anchalDailyProgressFSSNFSS Boost StageToday Koji came to the lab to help me out
with the FSS and give me few tips.

We made some changes to the boost
 NorthFSSBosstStageTF.pdf 
  2517   Wed Jan 22 16:00:26 2020 anchalDailyProgressFSSTTFSS OLTFs with Maximum GainRepeated these measurements with maximum
possible gain values in the FSS loops.


 FSS_OLTF.pdf 
ELOG V3.1.3-