LOG-IN
Displaying reports 1-25 of 37865.Go to page 1 2 3 4 5 6 7 8 9 10 End
AdV-AEI Squeezer Integration (General)
Print this report.
Schreiber, Mehmet, Vahlbruch, Zendri, Ciani, Vardaro, Masserot, Bonnand, Mours, Eisenmann, Sorrentino; Delaurentis, Sequino,... - 23:45, Wednesday 23 May 2018 (41541)Get code to link to this report
Squeezing: Search for coherent control error signal
After alignment work, the squeezer was put in squeezing mode and the beam send to the interferometer. To make a long story short, we finally saw the 7 MHz of the squeezer sideband on the B1 photodiode as shown in the figure taking in low-noise_3 mode were the purple line is with the shutter off, blue line with the shutter on.

The amplitude of this 7 MHz line was changing on a few second time scale, probably due to alignment.

No obvious effect on the shot noise level was observed, but the noise level is anyway fluctuating significantly without the squeezer on a few seconds time scale, again probably due to alignment (see the second figure).
Images attached to this report
41541_20180523234454_squezeeronoff.png 41541_20180523234504_ffttime.png
Detector Operation (Operations Report)
Print this report.
Nenci - 23:08, Wednesday 23 May 2018 (41540)Get code to link to this report
Operator Report - Evening Shift 23/05

The shift has been dedicated to the planned activity (Squeezer Alignment -> Coherent Control loop). Commissioning Mode stopped at 21:07 UTC but work stil in progress.

VPM

  • 15:30 UTC - InfraMoni restarted in order to change the thresholds of  'HVAC..DET_FREQ_IN' (request of the system expert).
  • 17:06 UTC - 'FbmStDy' crashed/restarted;
  • 17:15 UTC - 'LockMoni' restarted in order to change the thresholds of 'B4_112MHz_MAG_mean' (request of the system expert).
  • 19:14 UTC - 'DETMAIN' crashed/restarted;

INF

19:12 UTC - the detection lab UTA has been restored in "Portata Ridotta".

AdV-COM (AdV commissioning (1st part) )
Print this report.
bersanetti, ruggi, boschi - 20:07, Wednesday 23 May 2018 (41539)Get code to link to this report
LOW_NOISE_3 restored, solved issue with the CoilsSbNE process

Yesterday we observed the systematic unlock while trying to reach LOW_NOISE_2; after another unsuccessful trial, today we tried to go manually to such state, and it worked, so everything was fine at the SUS level.

After some digging, we found out that the problem was on the CoilsSbNE process, which was killed and restarted lately; unfortunately, some leftovers were still alive, as it appeared in the process list (only two processes per box should exist):

bersanet@olserver121:~  $ ps aux | grep CoilsSbNE
168:virgorun 14825  6.3  0.1 656892 14688 ?        SNl  May17 617:38 python /virgoApp/PySb/v3r1p0/scripts/PySb.py /virgoData/VirgoOnline/CoilsSbNE.cfg CoilsSbNE
188:virgorun 26379  0.0  0.2 656892 16520 ?        SN   May21   0:00 python /virgoApp/PySb/v3r1p0/scripts/PySb.py /virgoData/VirgoOnline/CoilsSbNE.cfg CoilsSbNE
194:virgorun 27485  8.7  0.3 656636 31784 ?        SNl  May21 231:20 python /virgoApp/PySb/v3r1p0/scripts/PySb.py /virgoData/VirgoOnline/CoilsSbNE.cfg CoilsSbNE
195:virgorun 27495  0.0 13.4 1490948 1099496 ?     SN   May21   0:43 python /virgoApp/PySb/v3r1p0/scripts/PySb.py /virgoData/VirgoOnline/CoilsSbNE.cfg CoilsSbNE
 

Possibly what happened and partly hid the problem was the fact that ITF_LOCK was started before this operation, so it was talking with the old cm name of the process, while my terminal was launched afterwards and talked to the process actually alive. We stopped the process from VPM, killed the zombies and restarted the process without issue. The automatic switch to LOW_NOISE_2 (and _3) was achieved again.

AdV-ISC (Alignment control scheme conceptual design)
Print this report.
casanueva - 18:00, Wednesday 23 May 2018 (41535)Get code to link to this report
SSFS OLTF check

Last week we injected some noise on the SSFS at recombined (entry 41411). This allowed us to tune several noises to try to characterize better the loop. I took a look today to these measurements, but the coherence is not very good, since when we are in recombined, the corrections sent are very high and we soon saturate.

However, I also took a look to the measurements took by Antonino and Annalisa the same day in the afternoon, this time in Low Noise 3 (entry 41417). As in Low Noise 3 we have much less correction being sent the noise injections are very good, and I tried to make a first estimation of the status of the loop by comparing them with the modelled OLTF (FIgure 1). Notice that at this point the third order boost was already engaged (with some extra digital noise which should be lower now).

  • The UGF at the moment of the measure is 8.5 kHz. The phase margin is not veyr big (~20deg) and the high gain stabiilty margin is ~15kHz. We should be able to increase the gain up to 10-12 kHz.
  • To match the measurement it was necessary to add a delay of 11 us to the SSFS loop (in the past it was 10 us).
  • I also tried to fit the crossing frequency between both loops (IMC and SSFS) by fitting the structure we see in the phase between 800 and 2 kHz. I had to decrease the crossing point by a factor almost 2 to fit this feature, which would correspond to a crossing frequency of ~70 Hz. However, this is not in agreement with the adjustment we had to do to get something stable (we have increased the gain of the IMC loop by a factor 2).
  • Notice also that there are two new structures around 1kHz!

I would like to understand better the changement on the crossing point. For this I think we need to make an extra noise injection at lower frequencies (this would make more clear the position of the crossing gain, since we would see it on the amplitude) and also a measurement of the loop of the IMC/RFC to cross-check the model.

Images attached to this report
41535_20180523175957_ssfsmeasurementsmodel.png 41535_20180523180003_ssfscrossingmodel.png
Injection system (General activities)
Print this report.
pillant, de rossi, fiori, paoletti - 17:33, Wednesday 23 May 2018 (41538)Get code to link to this report
Fast unlock fishing

During the night we had a period of fast unlock (see attached plot) but unfortunatly we

were not able to found a real coincidence with the magnetometer.

Anyway we think that the problem may be related to signals contamination instead of

rampeauto sensitivity.

More investigation needed ...

Images attached to this report
41538_20180523173354_notedel22052018.png
AdV-AEI Squeezer Integration (external squeezer table)
Print this report.
de laurentis, sorrentino, sequino, eisenmann, bonnand - 17:21, Wednesday 23 May 2018 (41536)Get code to link to this report
Comment to Alignment and mode matching of SQZ BAB on OMC (Click here to view original report: 41521)
During yesterday's shift we were unable to move the folding mirror underneath the Faraday isolator on SDB1 because of a communication error with the picomotor controllers.
Detector Operation (Operations Report)
Print this report.
Gherardini - 15:59, Wednesday 23 May 2018 (41533)Get code to link to this report
Operator Report - morning shift 23/05
This morning I found the itf not locked, before starting the activity on squeezer alignment both the cavities had been relocked to recover the good mirrors alignment; the activity inside the detection lab started at 7:00utc and it went on all the shift.

-vpm
INJ_MAIN restarted at 6:48utc because of crashed.

-inf
the detection lab UTA is still working in "Portata Nominale".
AdV-COM (AdV commissioning (1st part) )
Print this report.
pillant - 15:28, Wednesday 23 May 2018 (41532)Get code to link to this report
56MHz Modulation depth in O2

During an Fmoderr in O2, the 56MHz side band was visible on the RFC (see attached plot).

The modulation depth of was of about 0.16rad within 100um range of fmoderr tuning.

GPS from 1186495111.25 to 1186495123.45

Waiting for a calm periode to remeasure it now and compare...

Images attached to this report
41532_20180523152634_m56mhzo2.png
AdV-COM (AdV commissioning (1st part) )
Print this report.
Boschi - 12:36, Wednesday 23 May 2018 (41530)Get code to link to this report
Comment to BS glitches (Click here to view original report: 41516)

The MCH port statistics that log board to board communication problems have been checked and seem to exclude hardware issues. Moreover the keep sample policy is used in both MIR and MAR boards. We will continue the investigation.

AdV-COM (AdV commissioning (1st part) )
Print this report.
Allocca - 12:21, Wednesday 23 May 2018 (41529)Get code to link to this report
Comment to 6MHz modulation depth (Click here to view original report: 41496)

Notice that the recycling gain of the 56 MHz as seen by the PD1 and PD2 photodiodes is the same, provide that the correct proportion factor between B1p and B4 photodiodes is used to compute the MICH fringe condition for the 56 MHz sideband.

Images attached to this comment
41529_20180523122005_recg112pd1pd2.png
Virgo Runs (C9)
Print this report.
narnaud - 11:47, Wednesday 23 May 2018 (41528)Get code to link to this report
Comment to Duty Cycle of the C9 Run (Click here to view original report: 41499)

A few more plots about C9.

Images attached to this comment
41528_20180523114523_plotdqmetaitfmodestripchartc9.png 41528_20180523114534_plotrangesbnsc9.png 41528_20180523114545_sciencebestc9.png 41528_20180523114649_lockstatslockingsequencesc9.png 41528_20180523114718_sciencestatssciencesegmentsc9.png
AdV-COM (AdV commissioning (1st part) )
Print this report.
Paoletti - 11:13, Wednesday 23 May 2018 (41526)Get code to link to this report
Comment to 56MHz modulation loss (Click here to view original report: 41500)

A quick check of the RF 56MHz chain does not show any deviation from what expected.

LNFS signal generator is set at +12dBm, RF distribution sends -3dBm to the power amplifier, and the latter has a gain of 33.6dB which provides +30.6dBm (~1W) to the cable that goes at the EOM on the optical bench.

Note that the usual -3dB SMA power attenuator in front of the EOM has been removed since the beginning of the RF power increase.

Note also that the power amplifier for the 56MHz is not the usual (+30dBm ZHL-3A+), because it was modified with a +33dBm ZHL-1-2W+ to allow the power increase within a safety margin.

Virgo Runs (C9)
Print this report.
bersanetti - 10:44, Wednesday 23 May 2018 (41525)Get code to link to this report
Comment to Analysis of the unlocks during the run (Click here to view original report: 41492)

The unlocks due to DARM oscillating at 27 Hz are caused by the fact that lately, even if OMC1 locks at the same B1s2 power ~ 1.5 mW, the intercalibration between RF and DC readout has changed and DARM falls down to the lower end of the stability region and sometimes unlocks at this stage. This has been cured for the time being by changing the DARM gain at the same time of the hand-off of the error signal; however, since the same change of the gain happens in the opposite way a bit earlier in the lock acquisition, it makes more sense to recalibrate the DC error signals, which should only make the final DARM gain to be changed and the DC readout lock acquisition smoother.

Images attached to this comment
41525_20180523104406_darm27hz.png
AdV-COM (AdV commissioning (1st part) )
Print this report.
casanueva - 09:16, Wednesday 23 May 2018 (41524)Get code to link to this report
Comment to 6MHz modulation depth (Click here to view original report: 41496)

I have taken a closer look to the different signals used to build up the error signal of MICH. I found no explanation so far for the increase on the level noise (Figure 1). Moreover, taking a look to this weekend data, we can see that the spectrum of both 112 and both DCs is the same (Figure 2).

We would like to make a test and come back to the normalization using the other PD and check whether we recover the level of last week or is not dependent on the normalization.

Images attached to this comment
41524_20180523091418_180522checksprb1.png 41524_20180523091459_180522wepd1pd2.png
AdV-AEI Squeezer Integration (external squeezer table)
Print this report.
mwas - 09:09, Wednesday 23 May 2018 (41523)Get code to link to this report
Comment to Alignment and mode matching of SQZ BAB on OMC (Click here to view original report: 41521)
The B1s2 photodiode shutter was closed and the vbias switched off during this work (see figure), which explains why there was no signal visible on the PD.
Most B1* photodiodes have the shutter closed and vbias switched whenever the ITF is put in the DOWN state, and the PDs need to be enabled manually when the automation is not used.
Images attached to this comment
41523_20180523090642_screenshotfrom20180523090608.png
AdV-DAQ (Data Acquisition and Global Control)
Print this report.
letendre, masserot, mours - 08:59, Wednesday 23 May 2018 (41522)Get code to link to this report
DAQbox 20 and 47 used for timing tests
The DAQboxes 20 and 47 have been switched off/on and a new prototype of a timing mezzanine installed in the slot 3 of the DAQbox 20. Timing tests will be performed today on these two DAQboxes that are not used since they are dedicated to the SIB2 bench/SBE control that is still blocked.
AdV-AEI Squeezer Integration (external squeezer table)
Print this report.
de laurentis, sorrentino, sequino, eisenmann, bonnand - 02:26, Wednesday 23 May 2018 (41521)Get code to link to this report
Alignment and mode matching of SQZ BAB on OMC
Goal of the shift was to align and mode-match the bright beam from the squeezer on the OMC. We started by opening the shutter on SDB1, and by rotating the polarisation of the waveplate on the SDB1 Faraday to increase the power of the beam from SDB1 to the SQZ bench by a factor 2 as in entry 40668.

We then centered the BAB and the ITF beams on two diaphragms with 1 m path separation by acting on the SQZ steering mirror. At this point, we unlocked the IMC and misaligned the IMC end mirror to avoid the ITF beam to reach the detection bench: in such conditions we could see the spot of BAB on the B1p camera (see first attached image).

We scanned the OMC1 temperature and we could detect the different transmission modes of the BAB on the B1s2 camera, see second to fourth attachment.

We spent quite some time in steering the BAB to improve the alignment mismatch, with little success. The best matching we got was of the order of 30%. The last plot shows the total power on the B1s2 during a typical OMC scan (the SNR on the B12s photodiode is not enough to detect transmission modes).

We'll have to continue this work tomorrow morning.

We closed the shutter on SDB1, tuned the SDB1 Faraday for maximum transmission, and relocked the OMC.
Images attached to this report
41521_20180523021616_45.png 41521_20180523021944_25.png 41521_20180523021957_55.png 41521_20180523022046_18.png 41521_20180523022118_46.png
Comments related to this report
de laurentis, sorrentino, sequino, eisenmann, bonnand - 17:21, Wednesday 23 May 2018 (41536)
During yesterday's shift we were unable to move the folding mirror underneath the Faraday isolator on SDB1 because of a communication error with the picomotor controllers.
mwas - 09:09, Wednesday 23 May 2018 (41523)
The B1s2 photodiode shutter was closed and the vbias switched off during this work (see figure), which explains why there was no signal visible on the PD.
Most B1* photodiodes have the shutter closed and vbias switched whenever the ITF is put in the DOWN state, and the PDs need to be enabled manually when the automation is not used.
Images attached to this comment
41523_20180523090642_screenshotfrom20180523090608.png
Injection system (General activities)
Print this report.
pillant - 02:10, Wednesday 23 May 2018 (41520)Get code to link to this report
Fast unlock investigation

INJ in nominal condition

ITF down for the night...

Optical characterization (Optical characterization)
Print this report.
Allocca - 23:41, Tuesday 22 May 2018 (41519)Get code to link to this report
Comment to CMRF measurement and working point exploration (Click here to view original report: 41417)

The frequency independent coupling is rather related to a losses asymmetry, even though a deeper analysis is needed to confirm it.

As said in today's commissioning meeting, hereafter the complete list of GPS with all the noise injections which we performed, including the less loud once. Every injection lasts about 2 minutes. 

The injections were performed using two different kinds of filters, whose band is specified for each GPS value.

1210526709  May16,18-17:25:09 UTC  (May16,18-19:25:09 CEST)
colored noise amp 5 10 - 200Hz
1210526709  May16,18-17:25:09 UTC  (May16,18-19:25:09 CEST)
colored noise (10 - 200Hz) amplitude 5 
 
1210526799  May16,18-17:26:39 UTC  (May16,18-19:26:39 CEST)
colored noise (10 - 200Hz) amplitude 10
 
1210526923  May16,18-17:28:43 UTC  (May16,18-19:28:43 CEST)
colored noise (10 - 200Hz) amplitude 12
 
 
1210527010  May16,18-17:30:10 UTC  (May16,18-19:30:10 (below some CEST)
colored noise (10 - 200Hz) amplitude 15 
 
1210530324  May16,18-18:25:24 UTC  (May16,18-20:25:24 CEST)
colored noise amp 10 (200 - 1KHz)
 
 
1210530408  May16,18-18:26:48 UTC  (May16,18-20:26:48 CEST)
colored noise amp 20 (200 - 1KHz)
 
 
1210530898  May16,18-18:34:58 UTC  (May16,18-20:34:58 CEST)
colored noise amp 30 (200 - 1KHz)
 
1210531145  May16,18-18:39:05 UTC  (May16,18-20:39:05 CEST)
colored noise amp 40 (200 - 1KHz)
1210530324  May16,18-18:25:24 UTC  (May16,18-20:25:24 CEST)
colored noise amp 10 200 - 1KHz
 
 
1210530408  May16,18-18:26:48 UTC  (May16,18-20:26:48 CEST)
colored noise amp 20 200 - 1KHz
 
(dataDisplay often freezes)
off
 
1210530898  May16,18-18:34:58 UTC  (May16,18-20:34:58 CEST)
colored noise amp 30 200 - 1KHz
 
1210531145  May16,18-18:39:05 UTC  (May16,18-20:39:05 CEST)
colored noise amp 40 200 - 1KHz
 
After moving the PR longitudinal position by 1 mm:
 
1210531509  May16,18-18:45:09 UTC  (May16,18-20:45:09 CEST)
colored noise amp 10 (10 - 200Hz)
 
1210531587  May16,18-18:46:27 UTC  (May16,18-20:46:27 CEST)
colored noise amp 15 (10 - 200Hz)
 
1210531853  May16,18-18:50:53 UTC  (May16,18-20:50:53 CEST)
colored noise amp 20 (10 - 200Hz)
 
1210532015  May16,18-18:53:35 UTC  (May16,18-20:53:35 CEST)
colored noise amp 25 (10 - 200Hz)
 
1210532161  May16,18-18:56:01 UTC  (May16,18-20:56:01 CEST)
colored noise amp 30 (10 - 200Hz)
 
1210541459  May16,18-21:30:59 UTC  (May16,18-23:30:59 CEST)
colored noise amp 10 (200 - 1KHz)
 
1210541541  May16,18-21:32:21 UTC  (May16,18-23:32:21 CEST)
colored noise amp 20 (200 - 1KHz)
 
1210541665  May16,18-21:34:25 UTC  (May16,18-23:34:25 CEST)
colored noise amp 30 (200 - 1KHz)
 
1210541796  May16,18-21:36:36 UTC  (May16,18-23:36:36 CEST)
colored noise amp 40 (200 - 1KHz)
 
1210541541  May16,18-21:32:21 UTC  (May16,18-23:32:21 CEST)
colored noise amp 20 200 - 1KHz
 
 
1210541665  May16,18-21:34:25 UTC  (May16,18-23:34:25 CEST)
colored noise amp 30 200 - 1KHz
 
 
1210541796  May16,18-21:36:36 UTC  (May16,18-23:36:36 CEST)
colored noise amp 40 200 - 1KHz
 
1210531509  May16,18-18:45:09 UTC  (May16,18-20:45:09 CEST)
colored noise amp 10 10 - 200Hz
 
 
 
1210531587  May16,18-18:46:27 UTC  (May16,18-20:46:27 CEST)
colored noise amp 15 10 - 200Hz
 
 
1210531748  May16,18-18:49:08 UTC  (May16,18-20:49:08 CEST)
colored noise amp 5 10 - 200Hz
(trying to improve coherence with darm?!?!?)
 
1210531853  May16,18-18:50:53 UTC  (May16,18-20:50:53 CEST)
colored noise amp 20 10 - 200Hz
 
1210532015  May16,18-18:53:35 UTC  (May16,18-20:53:35 CEST)
colored noise amp 25 10 - 200Hz
 
1210532161  May16,18-18:56:01 UTC  (May16,18-20:56:01 CEST)
colored noise amp 30 10 - 200Hz
1210531509  May16,18-18:45:09 UTC  (May16,18-20:45:09 CEST)
colored noise amp 10 10 - 200Hz
 
 
 
1210531587  May16,18-18:46:27 UTC  (May16,18-20:46:27 CEST)
colored noise amp 15 10 - 200Hz
 
 
1210531748  May16,18-18:49:08 UTC  (May16,18-20:49:08 CEST)
colored noise amp 5 10 - 200Hz
(trying to improve coherence with darm?!?!?)
 
1210531853  May16,18-18:50:53 UTC  (May16,18-20:50:53 CEST)
colored noise amp 20 10 - 200Hz
 
1210532015  May16,18-18:53:35 UTC  (May16,18-20:53:35 CEST)
colored noise amp 25 10 - 200Hz
 
1210532161  May16,18-18:56:01 UTC  (May16,18-20:56:01 CEST)
colored noise amp 30 10 - 200Hz
1210526709  May16,18-17:25:09 UTC  (May16,18-19:25:09 CEST)
colored noise amp 5 10 - 200Hz
1210526709  May16,18-17:25:09 UTC  (May16,18-19:25:09 CEST)
colored noise amp 5 10 - 200Hz
 
 
1210526799  May16,18-17:26:39 UTC  (May16,18-19:26:39 CEST)
colored noise amp 10 10 - 200Hz
 
1210526923  May16,18-17:28:43 UTC  (May16,18-19:28:43 CEST)
colored noise amp 12 10 - 200Hz
 
 
1210527010  May16,18-17:30:10 UTC  (May16,18-19:30:10 (below some CEST)
colored noise amp 15 10 - 200Hz
 
 
1210527152  May16,18-17:32:32 UTC  (May16,18-19:32:32 CEST)
stop noise
1210526709  May16,18-17:25:09 UTC  (May16,18-19:25:09 CEST)
colored noise amp 5 10 - 200Hz
 
 
1210526799  May16,18-17:26:39 UTC  (May16,18-19:26:39 CEST)
colored noise amp 10 10 - 200Hz
 
1210526923  May16,18-17:28:43 UTC  (May16,18-19:28:43 CEST)
colored noise amp 12 10 - 200Hz
 
 
1210527010  May16,18-17:30:10 UTC  (May16,18-19:30:10 (below some CEST)
colored noise amp 15 10 - 200Hz
 
 
1210527152  May16,18-17:32:32 UTC  (May16,18-19:32:32 CEST)
stop noise
Detector Operation (Operations Report)
Print this report.
berni - 23:00, Tuesday 22 May 2018 (41518)Get code to link to this report
Operator report - Afternoon shift 22 May
The first hour of the shift was dedicated to ITF recovery after the Maintenance; unfortunately we were not able to recover the ITF standard conditions because the it was not able to reach LOW_NOISE_2.

At 15:00 UTC started the work on squeezing alignment in DET lab with the ITF locked in RECOMBINED.
At 15:42 the squeezing team paused INJ_MAIN to unlock the IMC; then at 19:53 they misaligned also the MC mirror (see attached plot) and I put the node SUS_NE and SUS_WI in MISALIGNED.
At 21:00 UTC under suggestion of Gabriel I disabled the AA of the IMC.
Activity on squeezing alignment in in progress; after that INJECTION on call will be contacted to relock the IMC and to perform measurement on it during the night.

INF
At 15:00 UTC i put set the UTA DET in "Portata Nominale".

SOFTWARE
FnmMoniUser restarted at 18:06 UTC after a crash.
CoilSbNI restarted at 20:32 after a crash.
Images attached to this report
41518_20180522224207_imcunlock.gif
Optical characterization (Optical characterization)
Print this report.
mwas - 21:55, Tuesday 22 May 2018 (41517)Get code to link to this report
Comment to CMRF measurement and working point exploration (Click here to view original report: 41417)
Looked in more detail at the SSFS noise projection during the SSFS noise injection.

Figure 1, shows the usual noise budget, with a simple frequency independent coupling of laser phase noise to the B1 DC power fluctuations in pink. In cyan is PRCL noise coupling into DARM, this comes from SSFS noise entering into PRCL sensing and then being reinjected by the PRCL loop.
Note that the measured strain from DARM (blue curve) has a dip at 100Hz, this seems to be the internal noise budget calibration going bad (DARM line hidden by SSFS noise injection?), the official h(t) (black curve) doesn't have this feature.

Figure 2, using the transfer functions from the noise budget, adjusting their gains slightly and adding the PRCL (blue) and SSFS (red) noise coherently allows to have a nice overall projection (yellow) that matches very well the measured h(t) (purple), including the dips at 180Hz and 230 Hz, and the wider bump at 300-400Hz, coming from the interference between noise coupling directly from SSFS to B1_DC and indirectly through the PRCL loop.

This would confirm that the direct optical coupling of SSFS to B1_DC/DARM is frequency independent. I do not remember if that corresponds to finesse or losses asymmetry.
Images attached to this comment
41517_20180522214322_screenshotfrom20180522213907.png 41517_20180522214327_screenshotfrom20180522214200.png
AdV-COM (AdV commissioning (1st part) )
Print this report.
majorana - 20:05, Tuesday 22 May 2018 (41516)Get code to link to this report
BS glitches
The glitches injected through BS angular Local Control, are still there. A deeper check on the HW and possible disturbance affecting the control line have to be performed.
The glitches are clear on B1p and originate by Tx marionette control.
- The SLED source does not seem the main cause., as the same unit is used for Tz.
- The amplifier was replaced with a new one a week ago.
- The glitches are not related magnetic disturbances in CD.

=> probably control boards (driving ?) can be checked
=> the optical line can be re-checked (fibre BS)
=> PSD substitution (at last)
Images attached to this report
41516_20180522200453_bsglitchness.png 41516_20180522200521_bsz.png
Comments related to this report
Boschi - 12:36, Wednesday 23 May 2018 (41530)

The MCH port statistics that log board to board communication problems have been checked and seem to exclude hardware issues. Moreover the keep sample policy is used in both MIR and MAR boards. We will continue the investigation.

AdV-INJ (Input Mode Cleaner cavity)
Print this report.
derossi, pillant, genin, fiori - 16:53, Tuesday 22 May 2018 (41508)Get code to link to this report
activities on the INJ system during the maintenance shift

this morning during the maintenace we performed several activities, reported below.

-  investigations about the fast unlocks. We went in the injection electronic room (where  the rack of the rampeauto is situated). Like in the past it has been noticed that some IMC unlocks are related to the circuit in this room (for example some unlocks are produced when switching on/off the oscilloscope near the rampeauto, when switching on/off the lights,... ).

We closed the rack for the rampeauto to be shielded, but unlocks were still produced.

We then plugged an antenna on the oscilloscope next to the rampeauto and we found out an oscillation at 43 kHz, whose amplitude increases a lot next to the neon lights. We then tried to swtich off the light system from the circuit breaker but it doesn't disappear, on the other hand it is less noisy. However, we cannot let the lights circuit off since it is the same circuite as the one for the badge system.In conclusion, for the moment we have observed this possible noise source, which is somehow increased by the neon lights, but we still haven' t identified its source.

We also found out that the rampeauto rack is not connected to the ground. We then connected it, but unlocks still occurred.

Mrs Flowers installed a magnetometer close to the rampeauto in order to monitor related magnetic perburbations.

- verification of the 56 MHz tuning. We unplugged the 56 MHz RF source and with a spectrum analyzer we directly verified the tuning on the EOM. The resonant circuit it's well centered on 56.437MHz with a Q of about 55.

Note : a piezoelectric resonances of the crystal is located on the modulation frequency

- measurement of the gain margin of the IMC locking loop. We can at present lock with a gain margin of 4 dB (from 16 to 20 dB) that is really weak.

- PMC perturb on the slave laser :

In order to be able to unlock the laser before the EIB without going in the laser lab, we plugged the PMC pertub DAC on the Slave Perturb with 10dB attenuation.

With 8V sent to the PMC offset the, the slave laser unlocks.

- recentering of the quadrants in the diagnostic box.

From the DMS alarm laser ampli we found a bad centering of the quadrants of the diag box on the laser bench, probably moved by mistake while touching the 14 MHz EOM. We recentered them (plot 2)

- reduction of the correction on the BPC. We did it by remote using picomotors (plot 1)

Images attached to this report
41508_20180522151513_bpc.png 41508_20180522151736_pslampli.png
AdV-TCS (CO2 laser projector)
Print this report.
nardecchia, aiello - 16:52, Tuesday 22 May 2018 (41514)Get code to link to this report
CO2 benches maintenance activity

During the maintenance we checked the status of the CO2 benches. We also performed the power calibration of three waveplates (two DASes and the CH lines) on each bench.

The proper operation of the repaired chiller has also been tested.

AdV-DAQ (Data Acquisition and Global Control)
Print this report.
letendre,masserot,mours - 16:41, Tuesday 22 May 2018 (41513)Get code to link to this report
GPS Timing troubles

Several GPS troubles occured since  end of March,2018.

The following plot shows that for each DaqBox driven by the GPS 10MHz clock the  timing error increase since May14,2018. One possible cause could be that the GPS 10MHz clock  seems not to be stabilized anymore.

To fix these different issues, a temporary timing setup based on DaqBox  will be installed until a new GPS atomic receiver will available.

Images attached to this report
41513_20180522164206_timingtroubledaqbox10mhz.png