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Reports until 11:44, Tuesday 08 March 2016
LHO General
bubba.gateley@LIGO.ORG - posted 11:44, Tuesday 08 March 2016 (25933)
LVEA Main Crane Rail Shimming
The LVEA main crane rail shimming as suggested by the survey crew from Duane Hartman & Associates Inc. has been completed. A copy of the shim changes will be entered in the DCC soon.
H1 TCS (TCS)
aidan.brooks@LIGO.ORG - posted 10:14, Tuesday 08 March 2016 - last comment - 18:56, Tuesday 08 March 2016(25932)
Nominal TCS power levels for O2 - ITM substrate lens only

The attached plot (and script) shows the nominal TCS power levels required for O2 to correct for just the ITM substrate lenses.

The following values are assumed:

The bottom line is that we will cease to need central heating around 45W on ITMX and 30W on ITMY and will need to start using the RHs to compensate for the thermal lenses. No consideration is yet given to HOM correction with annular CO2 heating.

 
Subject: Re: RC as-built design
Date: May 14, 2015 at 7:54:37 PM EDT

Hi All,

The value of the thermal lens that was always used when adjusting the cavities is 50 km.  

The issue which caused all of the confusion last summer was one of definition; i.e. what does it mean to have a 50 km thermal lens.  The plots Muzammil put together, on which the decision to include the thermal lens was based, modeled the thermal lens as being inside the ITM.  The model we used to adjust the optic positions had the 50 km thermal lens immediately in front of the ITM.  The effective focal length in the two cases differs by a factor of n (the index of refraction), with it being stronger in the model which was used to calculate the positions.  Because of this the positions were tuned to have a slightly stronger thermal lens than was originally decided on based on Muzammil's plots.  

Fortunately, Lisa and I discovered that this is essentially a non-issue since the length changes needed to tune for the two different thermal lenses are less than the length changes needed to compensate for tolerances in the measured radii of curvature of the optics.  
 
Images attached to this report
Non-image files attached to this report
Comments related to this report
kiwamu.izumi@LIGO.ORG - 18:56, Tuesday 08 March 2016 (25946)

Thank you Aidan for working on this.

Speaking of the thermal lensing, we (the LHO crews) have been discussing a possible TCS pre-loading strategy. Here are some summary points of our (future) strategy:

  • We dial the ITMY ring heater to the value that is optimized for 50 W PSL power. According to your plot, a ring heater power of 1.3 W seems the optimum.
    • We let it stay there all the time regardless of whether the interferometer is locked or not.
    • We do this because the ring heater can be too slow to keep up with the interferometer's thermal state
  • On the other hand, we do not heat up the ITMX ring heater (at least at the beginning of the test).
    • Perhaps we will perform a fine adjustment later with the fully locked interferometer with 50 W input.
  • Before the interferometer is locked, we engage both CO2 lasers to pre-heat the interferometer.
    • CO2X will be at 0.5 W according to your plot
    • CO2Y will be at 0.3 W according to your plot
  • Once the interferometer is locked and starts powering up, we turn off the CO2 lasers.
    • For the early phase, we are thinking of a simple power down with a step function.
    • As a next step, we will attempt transient compensation by applying pre-calculated CO2 requested power.
    • Cao has already looked into this transient compensation issue and had a matlab code ready to calculate various configurations.
  • We can play with the ETM ring heaters to see if we can maneuver away from the parametric instabilities.
    • I have not done any calculation for this yet.
  • As soon as the interferometer is unlocked, we set the CO2 back to the pre-heat settings in order not to cool down the interferometer.

Any comments/questions are welcome.

H1 SEI
thomas.shaffer@LIGO.ORG - posted 09:33, Tuesday 08 March 2016 (25931)
T240 Centering FAMIS #4366 and Bonus STS

All T240s prrof masses that within healthy range (< 0.3 [V]). Great!


Here's a list of how they're doing just in case you care:
ETMX T240 1 DOF X/U = 0.077 [V]
ETMX T240 1 DOF Y/V = 0.094 [V]
ETMX T240 1 DOF Z/W = 0.119 [V]
ETMX T240 2 DOF X/U = -0.199 [V]
ETMX T240 2 DOF Y/V = -0.246 [V]
ETMX T240 2 DOF Z/W = -0.094 [V]
ETMX T240 3 DOF X/U = 0.093 [V]
ETMX T240 3 DOF Y/V = -0.087 [V]
ETMX T240 3 DOF Z/W = 0.06 [V]
ETMY T240 1 DOF X/U = 0.03 [V]
ETMY T240 1 DOF Y/V = -0.042 [V]
ETMY T240 1 DOF Z/W = 0.005 [V]
ETMY T240 2 DOF X/U = -0.168 [V]
ETMY T240 2 DOF Y/V = 0.029 [V]
ETMY T240 2 DOF Z/W = 0.132 [V]
ETMY T240 3 DOF X/U = -0.001 [V]
ETMY T240 3 DOF Y/V = -0.003 [V]
ETMY T240 3 DOF Z/W = 0.1 [V]
ITMX T240 1 DOF X/U = -0.023 [V]
ITMX T240 1 DOF Y/V = 0.275 [V]
ITMX T240 1 DOF Z/W = 0.202 [V]
ITMX T240 2 DOF X/U = 0.24 [V]
ITMX T240 2 DOF Y/V = 0.262 [V]
ITMX T240 2 DOF Z/W = 0.296 [V]
ITMX T240 3 DOF X/U = 0.064 [V]
ITMX T240 3 DOF Y/V = 0.247 [V]
ITMX T240 3 DOF Z/W = 0.239 [V]
ITMY T240 1 DOF X/U = 0.192 [V]
ITMY T240 1 DOF Y/V = 0.068 [V]
ITMY T240 1 DOF Z/W = 0.116 [V]
ITMY T240 2 DOF X/U = 0.196 [V]
ITMY T240 2 DOF Y/V = 0.266 [V]
ITMY T240 2 DOF Z/W = 0.214 [V]
ITMY T240 3 DOF X/U = 0.121 [V]
ITMY T240 3 DOF Y/V = 0.214 [V]
ITMY T240 3 DOF Z/W = -0.149 [V]
BS T240 1 DOF X/U = 0.054 [V]
BS T240 1 DOF Y/V = 0.091 [V]
BS T240 1 DOF Z/W = 0.22 [V]
BS T240 2 DOF X/U = 0.162 [V]
BS T240 2 DOF Y/V = 0.237 [V]
BS T240 2 DOF Z/W = 0.231 [V]
BS T240 3 DOF X/U = 0.134 [V]
BS T240 3 DOF Y/V = 0.087 [V]
BS T240 3 DOF Z/W = 0.024 [V]
 

 


 

Jim W suggested that I run the script for the STS's as well while I'm here.

There are 1 STS proof masses out of range ( > 2.0 [V] )!
STS C DOF Z/W = 3.155 [V]


All other proof masses are within range ( < 2.0 [V] ):
STS A DOF X/U = -0.947 [V]
STS A DOF Y/V = 0.13 [V]
STS A DOF Z/W = -0.068 [V]
STS B DOF X/U = 0.886 [V]
STS B DOF Y/V = 0.62 [V]
STS B DOF Z/W = 0.563 [V]
STS C DOF X/U = -1.536 [V]
STS C DOF Y/V = -0.929 [V]
STS EX DOF X/U = 0.516 [V]
STS EX DOF Y/V = -1.076 [V]
STS EX DOF Z/W = 0.387 [V]
STS EY DOF X/U = 0.518 [V]
STS EY DOF Y/V = 0.683 [V]
STS EY DOF Z/W = -0.266 [V]

 


 

FAMIS #4366  closed
 

LHO FMCS (CDS)
carlos.perez@LIGO.ORG - posted 06:28, Tuesday 08 March 2016 (25930)
New File Servers Deployment
As part as Tuesday maintenance today March 8, 2016 CDS system admins will be deploying a new file system ( /Ligo ) the switch over will limit the ability to use any workstation or server that mounts /Ligo until the work is completed; Once the switch over on the MSR has been done, every workstation must be updated and restarted.
H1 General
lisa.barsotti@LIGO.ORG - posted 02:57, Tuesday 08 March 2016 - last comment - 14:53, Tuesday 08 March 2016(25929)
Quick summary of today's work
Sheila, Jenne, Matt, Rob, Evan, Lisa

Several things happened today, more details will be posted later:
  • we locked several times in low noise (note: ASC in the old configuration with DC (not RF90MHz) centering, see week-end entries for more details): the best range we saw today was about ~70 Mpc, due to some peaks in the spectrum higher than usual -- the 290 Hz was particularly higher than during O1;
  • in low noise Sheila made several ISI shaking tests, Robert did some investigations in parallel as well;
  • we looked at the coupling into the OMC at full power: this measurement needs to be repeated to make sure the conclusion we get is right, as the inferred coupling to the OMC would be significantly lower than what assumed from previous measurements;
  • Jenne took some DHARD open loop transfer functions as function of the DARM offset;
  • some off-line investigations to get hints of the mystery noise happened as well, more details will follow.
Some of these things are not finished as an earthquake hit us around 10pm local time; we waited for two hours for the noise to go down again, but we couldn't really relock robustly afterwards, even when the ground motion seemed back to normal (to be investigated). Some items for our to-do-list that came up tonight (to be merged with what we already have on the control room whiteboard) are:
  • inspired by Kiwamu's analysis, modulate the vertical position of optics and look for changes in the DARM noise;
  • (new entry): look at the DARM rms, and see if there is some loop optimization that can be done to minimize it (in particular, check if rms optimization advocated by Jeff at the last commissioning workshop happened or not);
  • in-depth analysis of frequency noise, in particular look for saturations in the common mode board;
  • close the loop on this OMC coupling, and if it is real, distinguish between mode mismatch vs misalignment - if it turns out that the alignment into the OMC is bad, resurrect deacon alignment (ECR already submitted and approved).
Comments related to this report
keita.kawabe@LIGO.ORG - 14:53, Tuesday 08 March 2016 (25935)

Higher-than-before jitter coupling seems to have made a lot of excess noise peaks. See these high coherence peaks between DARM and various IMC WFS signals (only WFS DC signals are shown).

It doesn't look like the intensity noise caused by the jitter (look at low coherence between DARM and ISS second loop signal, also IM4_TRANS_SUM coherence is low even when IM4_TRANS_PIT coherence is high).

Something seems to be excited on the PSL table (look at the coherence between DARM and PSL table accelerometer).

What happened in the PSL since Feb 26 2016 16:30 UTC when the IFO was in good low noise lock?

Images attached to this comment
H1 ISC
evan.hall@LIGO.ORG - posted 01:16, Tuesday 08 March 2016 - last comment - 15:47, Tuesday 08 March 2016(25928)
DARM-to-OMC coupling at full power

Lisa, Evan

We repeated the DARM-to-OMC coupling test (25852) at full power.

Tentatively, the change in the violin mode heights with the OMC locked and unlocked suggests only a 75 % coupling into the OMC (i.e., a 25 % loss).

We are not sure why the violin mode at 502.8 Hz is fatter with the OMC locked, so we would like to repeat this test with a calibration line.

Images attached to this report
Non-image files attached to this report
Comments related to this report
koji.arai@LIGO.ORG - 15:47, Tuesday 08 March 2016 (25939)

This 502.8Hz mode seems one of the violin mode for ITMX, accoding to the wiki https://awiki.ligo-wa.caltech.edu/aLIGO/H1%20Violin%20Mode

If that's true, just to be sure, you should use one of the ETM violin modes, or ETM cal line as you mentioned.

When I was doing a beacon scan using some of the violin modes, I found that the 45MHz modulation sidebands also had finite response to the violin modes.
Assuming this came from the motion of the ITMs, I learned that I needed to use the ETM motions in order to correctly figure out the signal mode matching.

H1 ISC (ISC)
matthew.evans@LIGO.ORG - posted 23:22, Monday 07 March 2016 (25927)
DARM noise, a simple budget

I made a quick "noise budget" which accounts for most of the H1 noise with just shot noise, coating thermal noise, a 1/f mystery noise, and a 1/f^4 "other noises" curve.  This is a much poorer version of the real noise budget, but it is enough to help with the mystery noise search.

Images attached to this report
Non-image files attached to this report
H1 General
cheryl.vorvick@LIGO.ORG - posted 22:49, Monday 07 March 2016 (25926)
Ops Eve Summary:

State of H1: locking well, and made it to Low Noise multiple times

Commissioning:

Site activities:

Current Status:

H1 General
lisa.barsotti@LIGO.ORG - posted 22:43, Monday 07 March 2016 (25925)
SensMon Range is back
Even if H1 had been brought back to low noise before the week-end, the SensMon was not properly showing the range. This was due to a change in the whitening filters in CAL_DELTAL_EXTERNAL_DQ that happened last week (see  Sheila's entry ). John Z updated SensMon to take the new filters into account (thanks John), so the range monitor is back, and the summary pages show it correctly. 
H1 SEI (SUS)
hugh.radkins@LIGO.ORG - posted 17:10, Monday 07 March 2016 (25913)
LHO BSC ISI Model Updates

WP 5765  See T1600062 for details of all updates.

SVN UP'd:

hugh.radkins@operator3:models 0$ svn up
U    isi2stagemaster.mdl
A    ISI_to_SUS_library.mdl
Updated to revision 12797.
hugh.radkins@operator3:models 0$ pwd
/opt/rtcds/userapps/release/isi/common/models
 

hugh.radkins@operator3:src 0$ pwd
/opt/rtcds/userapps/release/isi/common/src
hugh.radkins@operator3:src 0$ svn up
A    WD_SATCOUNT_vb.c
Updated to revision 12797.

Top Level Model edits:

Added Paths to all BSC top level models to calculate the SUSPOINT motion in the ISI.  Once these are working in the ISI model, the calc done in the SUS model and the IPC to the SUS will be removed.  See the attached for a before (left) and after (right) look at the model changes.
 

Images attached to this report
H1 AOS
sheila.dwyer@LIGO.ORG - posted 16:56, Monday 07 March 2016 (25920)
ALS DIFF a bit better

This morning we had a combination of moderately high winds (gusts up tp 30-35 mph) and microseism above the 90% percentile, this is a combination of ground motion conditions where we had trouble durring O1.

We attempted to lock several times, and probably would have been able to if we had just kept trying, although we had random locklosses at diffrent stages of the CARM  offset reduction. 

One thing that we know is a weak point in our acquisition now is the ALS DIFF loop, so Matt and I had a look at improving that loop.  We saw that our UIM control filter, which has some modest plant inversion to make the crossover between the ESD and UIM stable, was not quite right.  We had features just above 2 Hz which were causing us to nearly have a second UGF there, and gain peaking was clearly visible in our control signals.  This was predicted by the sus model and our filters, although reality was a little worse than what was predicted.  

The first attached screnshot is the OLG before (blue) and after (red).  You can see that there was a small dip that nearly had multiple ugfs just above 2 Hz, which is improved a little.  THe second screenshot shows the crossover measured by injecting at L1, the third one shows the change to the filter. 

With this filter, we were no longer able to engage the 1 Hz resonant gain in the DARM filter bank.  From our model it isn't clear why that would be, but we also don't see any reason why we need such an aggressive ResG at the moment, so we are leaving it out.  

Images attached to this report
LHO VE (VE)
gerardo.moreno@LIGO.ORG - posted 16:33, Monday 07 March 2016 (25921)
Manually over-filled CP3 at 00:05 utc

1/2 open LLCV bypass valve, and the exhaust bypass valve fully open.

Flow was noted after 95 seconds, closed LLCV valve, and 3 minutes later the exhaust bypass valve was closed.

Next over-fill on Thursday, March 9th before 23:59 utc.

LHO VE
kyle.ryan@LIGO.ORG - posted 16:11, Monday 07 March 2016 (25919)
Kyle & Gerardo -> Greased CS QDP80 rotor bearings using new AR555 grease


			
			
H1 ISC
kiwamu.izumi@LIGO.ORG - posted 15:17, Monday 07 March 2016 - last comment - 19:21, Monday 07 March 2016(25918)
cross spectrum analysis: now optical gain included

It turned out that all my previous analysis did not correct for the time-varying optical gain when calibrating the cross spectra into displacement even though I thought I have done it. I have recalibrated all the O1 data with the optical gain properly corrected.

Fortunately, the conclusions I have arrived so far qualitatively did not change.

Related alogs: 25847, 25768


Here are some plots with the newly calibrated cross spectra, mainly to show there is no drastic changes.

Fig.1 Band limited rms of the cross spectra in time series for the entireO1 run. The old data (without the optical gain correction) are show as "+" symbols while the recalibrated data are shown as dots.

Fig.2 Ratio of the band limited rms, (new data) / (old data). Notice that the high frequency bands (bands 3-8) tend to have larger displacement now. The low frequencies do not fluctuate as big as those for high frequencies as expected.

Fig.3 A naive correlation diagram in which the linear dependency between high frequency bands (bands 5-8) is still visible.

Fig.4 Time series plot of scaled band 8 BLRMS, LVEA temperature and scaled vertical sensors of various suspended optics.

Images attached to this report
Comments related to this report
kiwamu.izumi@LIGO.ORG - 18:21, Monday 07 March 2016 (25922)

A report on correlation with the optical gain.

It seems that the overall behavior of the optical gain shows correlation with the band limited rms. Is this calibration artefacts or something real ??

Darkhan provided me with kappa_c which was averaged over every 128 sec. In order for us to become less sensitive to glitches or some discontinuity in the Pcal line, we used kappa_c from the C02 frame that are smoothed by a median filter.  In the second figure, I overlaid the old rms data which I did not correct for kappa_c by accident (as described in the above entry). Both corrected and uncorrected rms show somewhat good correlation with the rms.

Images attached to this comment
Non-image files attached to this comment
kiwamu.izumi@LIGO.ORG - 18:38, Monday 07 March 2016 (25923)

The same analysis for the DARM cavity pole. Maybe correlated as well ?

Images attached to this comment
Non-image files attached to this comment
kiwamu.izumi@LIGO.ORG - 19:21, Monday 07 March 2016 (25924)

The attached is the DARM model that I have used for calibrating the cross spectra. OLGTF = sensing * (atst + apum ) * userd.

Non-image files attached to this comment
H1 General (OpsInfo, PSL)
edmond.merilh@LIGO.ORG - posted 14:24, Monday 07 March 2016 (25917)
PSL Weekly 10 day trends and Status
Laser Status:
SysStat is good
Front End power is 32.01W (should be around 30 W)
Frontend Watch is GREEN
HPO Watch is RED

PMC:
It has been locked 12.0 days, 22.0 hr 9.0 minutes (should be days/weeks)
Reflected power is 3.078Watts and PowerSum = 25.24Watts.

FSS:
It has been locked for 0.0 days 0.0 h and 15.0 min (should be days/weeks)
TPD[V] = 1.466V (min 0.9V)

ISS:
The diffracted power is around 8.465% (should be 5-9%)
Last saturation event was 0.0 days 0.0 hours and 15.0 minutes ago (should be days/weeks)

For further in-depth analysis of the trends, please refer to Jason O., Pete K. or Rick S.
Images attached to this report
H1 General (OpsInfo, PSL)
edmond.merilh@LIGO.ORG - posted 14:08, Monday 07 March 2016 (25916)
PSL Chiller Water
FAMIS#4140  closed
H1 CDS
james.batch@LIGO.ORG - posted 14:05, Monday 07 March 2016 (25915)
Restarted h1cam18 (Camera 18)
I have power-cycled camera 18 and restarted it's server. It appears to be working again.  My first try at just restarting the server didn't work, only after power cycling the camera did it appear to be working.
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