In my previous entry 23283 I only reported results for 3rd and 4th harmonic because for the 21 hours of data analysed there the damping filters of the fundamental and second harmonics for the test masses were activated.

As described in 23085 on 2015-11-04 we were allowed to turn off the damping filters for the fundamental and 2nd harmonics of ITMX and ITMY and we managed to get a 10 hours continuois lock of the detector. This happened from (UTC) 2015-11-04 06:35:00 to (UTC) 2015-11-04 16:15:00. (See attached plots of the damping filter GAINs nulling during the interval of interest and a detector state graph showing lock during the time of interest).

I looked at channel H1:OMC-DCPD_SUM_OUT_DQ downsampled to 8192Hz in order to be able to handle the considerable amount of data.

The attached spectrum of the 10 hours of data on a 0.5mHz resolution and 33 averages identifies (in red) the dominant peaks at the fundamental violin mode frequencies corresponding to the violin modes previously assigned to ITMX and ITMY (as per 17610).

Like in 23283 I used a line tracker (iWave) to track the frequency and amplitude of each fundamental mode of the violin modes of ITMX and ITMY. Attached are the summary plots for the locked modes at the top is the frequency as a function of time and at the bottom is the Log of the amplitude as a function of time. A first order polynomial is fitted to Log(Amp) in order to obtain the Q of that mode.

Looking at the iWave plot results we observe that very few modes show a clear ringdown (these are highlighted in bold on the table below), also some modes show actually an amplitude increase:

            Frequency                       Q                Delta_Q

   1.0e+09 *

   0.000000500053540                   0                   0

   0.000000500211188                   0                   0

   0.000000501090622   1.099263893173578   0.001406678163595

   0.000000501206991   0.387149689289317   0.000525686495200

   0.000000501255024                   0                   0

   0.000000501451642   0.836253670431456   0.000578382636001

   0.000000501607755                   0                   0

   0.000000501684000                   0                   0

   0.000000501748284                   0                   0

   0.000000501811170   0.672273711595517   0.000373649058032

   0.000000502622036                   0                   0

   0.000000502745387   0.287935668815574   0.000095512884649

   0.000000503007120   0.296739931868312   0.000046580713516

   0.000000503119439                   0                   0

   0.000000504805141                   0                   0

   0.000000504871717                   0                   0

NOTE: The Q of the trustworthiest ringdowns in this analysis are between 0.3 and 0.8 e9, in comparison with the 3rd and 4th harmonic measurements in 23283 which range 0.6 and 1.5 e9.

O1 days 53,54

model restarts logged for Tue 10/Nov/2015
2015_11_10 11:55 h1susauxex
2015_11_10 11:55 h1susauxey
2015_11_10 12:00 h1broadcast0
2015_11_10 12:00 h1dc0
2015_11_10 12:00 h1nds0
2015_11_10 12:00 h1nds1
2015_11_10 12:00 h1tw0
2015_11_10 12:00 h1tw1

Maintenance day, susaux model changes. DAQ restart: resync to susaux, add sdf chans to edcu.

model restarts logged for Mon 09/Nov/2015

no restarts reported

This is a belated report on comparing DARMOLGTF and PCAL2DARMTF measurements taken on Oct 28, 2015 (LHO alog 22928) vs. DARM model.

The comparison showed that measured sensing function residual have reduced to under 1% in a band [~30 ~500] Hz when comparing to a κtst and κC corrected DARM model. Also κ_pu is close to unity and cc pole frequency calculated from cal lines just before we started taking the TF measurements is 10 Hz higher than the one around October 15 TF measurements, and closer to 341 Hz, a value in the canonical DARM model. For previous kappa values see reports from previous similar analysis: LHO alog 22571, LHO alog 22552, LHO alog 22071.

Kappas used in the kappa corrected parameter file H1DARMparams_1130094627_kappa_corr are given below (notice that at this point we only apply κ_tst and κ_C). These are 60 minute mean kappas calculated from 60 s FFT SLM data starting at GPS 1130091000.

κ_tst = 1.012713
κ_pu = 1.003557
κ_A = 1.015523
κ_C = 0.980036
f_c = 344.154643 [Hz]

An updated comparison script and parameter files for the most recent measurements were committed to calibration SVN (r1759):

/trunk/Runs/O1/H1/Scripts/DARMOLGTFs/H1DARMparams_1130094627.m (r1751)
/trunk/Runs/O1/H1/Scripts/DARMOLGTFs/H1DARMparams_1130094627_kappa_corr.m
/trunk/Runs/O1/H1/Scripts/DARMOLGTFs/CompareDARMOLGTFs_O1.m
/trunk/Runs/O1/H1/Scripts/CAL_PARAM/plotCalparameterFromSLMData.m

Comparison plots were committed to CalSVN (r1779):

/trunk/Runs/O1/H1/Results/DARMOLGTFs/2015-10-28_H1DARM_O1_cmp_*.pdf

Title:  11/11/2015, Evening Shift 00:00 – 08:00 (16:00 – 00:00) All times in UTC (PT)
	
State of H1: 00:00 (16:00), The IFO locked at NOMINAL_LOW_NOISE, 22.1w, 77Mpc.  

Outgoing Operator: TJ

Quick Summary:  IFO is in Observing mode. Seismic activity is below 0.1 um/s. Microseism is centered around 0.4 um/s, however the slope is upward. Wind is calm to a gentle breeze (0 – 10 mph). 

yesterday I commited all outstanding svn local modifications to the userapps repository. This mainly covered filter files and observe.snap files, plus yesterday's susaux model files.

yesterday evening the observe.snap files for lsc,asc, omc,iscex and iscey were modified to accept the changes made when the dark offset script was ran. I have just checked these into SVN. Perhaps channels which are changed via MEDM or scripts should not be monitored by SDF, even though they are changed infrequently.

My first LSC fellow shift, and it didn't disappoint.

Arrived at 8am PST with IFO coming up to ~78 Mpc. Quiet running until a couple of ETMY DAC saturations. The GPS times of saturations are:
1131299869
1131301016
My understanding is that this is a frequently observed glitch, but the mechanism is not well understood.

After LLO lost lock, Chris was doing some opportunistic injections requested by the CW group. Unfortunately, not all of the injections were completed when H1 lost lock.

During the next lock stretch, while there were no observed ETMY DAC saturations, an unfortunate oscillation developed at 13:48 PST (21:48 UTC), observed strongly in H1:ISI-ETMX_ST1_CPS_X_LOCATION and also observed in H1:ASC-DHARD_Y_OUTMON/H1:ASC-DHARD_P_OUTMON. This continued for several minutes, looked to be settling down, but then increased to the point that we decided to try a test increase on the DHARD gain (we took H1 out of observing mode before this test). This was unsuccessful and H1 fell out of lock.

Following the lock loss, H1:ISI-ETMX_ST1_CPS_X_LOCATION continued to oscillate for ~10 more minutes before suddenly settling down without input from the operator. Investigations are ongoing by local site experts.

H1 has now resumed operating at ~78 Mpc.

• TITLE: "11/11 DAY Shift: 16:00-00:00UTC (08:00-16:00 PDT), all times posted in UTC"

• STATE Of H1: Observing at 79Mpc for almost an hour

• SUPPORT: Keita, Evan G, Jim W, Nutsinee, Cheryl

• SHIFT SUMMARY: Had a few issues with the ETMX ISI  swinging around. This seemed to also have been my problem with relocking yesterday. After lockloss, I would just wait for it to settle and then begin the normal relocking efforts.

• INCOMING OPERATOR: Jeff B

• ACTIVITY LOG:

• 16:08 Joe - To Xarm beam sealing
• 17:50 Karen - To mech room
• 18:04 Karen - Out
• 18:51 Odd 100Hz hump in DARM, and the RF45 noise seemed to pick up very slightly. This lasted only about 30 sec.
• 19:22 Lockloss - See alog
• 20:22 Observing
• 21:15 - Joe to Xarm beam sealing
• 21:54 - Start of odd ISI movement, this will later cause a lockloss
• 22:01 - Control signals look as though it will break lock at any moment so we added 3dB to the DHARD gains (suggested by Nutsinee)
• 22:02 - Lockloss
• 23:23 - Joe - back
• 22:31 - PRMI to DRMI transition Failed
• 23:18 - Observing

Observing at 79Mpc

After the last lockloss, I let the IFO sit in DOWN and waited for the ETMX ISI relax back to normal. I then resumed locking, and only had one hiccup where I had to adjust the recycling gain by hand during ENGAGE_ASC_PART1. This went well and after waiting for violin modes to damp a bit, we are at Nominal Low Noise and Observing.

An investigation on teh reason for the last lockloss is still ongoing.

As the IFO went into oscillations that have historically indicated it's headed for lockloss, I noticed a peak in MICH and some increased noise in PRCL around 15Hz.

I ran the DRMI_FOM template with 150 averages starting when the oscillations appeared until lock loss, 21:50UTC to 22:01:55UTC (Lockloss was at 22:02:24UTC).

DRMI displacements plot attached.

Jim W. pointed out that there was an oscillation in the control loops. ETMX ISI seemed to be moving quite a bit as well. This grew to the point that we knew we were about to lose lock. Nutsinee suggested an increase in DHARD gain by 3dB (based on a previous experience she had, and advice from Jenne and Sheila then). I changed their gain and after about 10 seconds or so it dropped.

The ETMX ISI is still has large movement in it, and not showing signs of relaxing at all. The control room is working on it, we will try to relock again as soon as we can.

came in today to find ISI HAM2,3 models each have a single CRC DAQ error as reported by the data concentrator (this is calculated 16 times a second). I found that these numbers are not trended anywhere, so I'll open an ECR to add them to the DAQ. I know that all the CRCs were zero when I left at 18:00 last night.

Note to operators, if you see CRC errors on the new CDS O1 Detail screen not related to restarts please alog this. TJ tested the new "!DAQ Clear Accumulated CRC" button when H1 was not in observation mode to clear them.

Observing at 78MPc.

Environment:

• Winds < 15mph
• Seismic: 0.03-0.1Hz = 0.04 um/s, 0.1-0.3Hz = 0.8 um/s
• Outside Temp: 56.4F/13.6C
• Inside temps: Good

Lockloss @ 19:22

LLO is down with some "high" winds. Chris Biwer will run a swept sine while there is an opportunity.

Beginning swept-sine test for CAL-INJ while LLO is down.

Activity Log: All Times in UTC (PT)

00:00 (16:00) Take over from TJ
02:40 (18:40) First of four large (mag 6.9 to 4.9) EQs in Chile. All four arrived within 30 minutes.
05:00 (21:00) Start initial alignment
06:19 (22:19) IFO locked at NOMINAL_LOW_NOISE, 22.1w, 78Mpc
06:24 (22:24) Cleared SDF and set intent bit to Observing
06:56 (22:56) Lockloss – mag 5.2 EQ on Mid-Pacific Ridge
07:30 (23:30) Relocked at NOMINAL_LOW_NOISE, 22.2w, 78mpc
	      No SDF differences flagged – Set Intent bit to Observing
08:00 (00:00) Hand off to Travis


End of Shift Summary:

Title: 11/10/2015, Evening Shift 00:00 – 08:00 (16:00 – 00:00) All times in UTC (PT)

Support: Keita, Betsy, Hugh, Vern, Marissa 

Incoming Operator: Travis

Shift Summary: Had problems locking the ALS green, mostly in X. Keita found the BSC-9 ISI had a large swing on the X platform location. (See #23293). The motion slowed down, and I was able to realign the ALS green for both arms. Tried relocking. Made it to DARM_1F before 4 large EQs hit Chile. Seismic motion is very high right now (See #23296). Waiting for things to settle and will try relocking. 

After seismic activities settled down to below 0.1 um/s and microseism dropped to 0.3 – 0.2 um/s, ran initial alignment. The IFO was locked at NOMINAL_LOW_NOISE. Cleared up several SDF issues, and set the intent bit Observing. Wind at the CS is a moderate breeze (13 – 18 mph) and light to gentle (4 – 12) at the ends and mids. 

Lockloss due to Mid-Pacific Ridge Earthquake. Seismic activity has rung up a bit, but is quickly coming down. Microseism did not change from 0.3 um/s. Wind is up to a fresh breeze (19 – 24 mph) in the CS. The wind at the ends and mids is still light to gentle breeze (4 – 12 mph). Will attempt to relock without doing an initial alignment.

IFO relocked easily without the need for a realignment. Back to Observing
   

 

This entry follows upon the entry 23167 where the frequency of the 3rd and 4th harmonic for the QUAD suspensions violin modes were identified. This entry is also complementary to Evan Hall's entry 22847 where similar Q's were measured with a different technique.

In this analysis, a line tracker (iWave) was applied over each of the identified 3rd and 4th harmonic frequencies (23167) on 21 hours of data during which the detector was continuously in Observing mode and with the damping filters turned off, data analysed started from 2015-10-21 21:30:00. The channel I used is H1:OMC-DCPD_SUM_OUT_DQ downsampled to 8192Hz in order to be able to handle the considerable ammount of data.

The line tracker was set to lock, on an automated way, to each of the monitored frequencies of interest. The tracker provides the frequency value which it is following and the amplitude of that frequency as a function of time. This information is provided in real time with the data being analysed. Although I automated the process the line tracker could not always lock to the mode of interest, in a few cases it locked to the wrong mode of higher amplitude and/or was not able to separate modes of high amplitude and close proximity. Therefore a targetted run had to follow the automated one.

The result of the analysis is summarised on the attached 'png' plots which shows; in each column the mode monitored with the top plot being the frequency tracked as a function of time and the bottom plot the 'log(Amplitude)' (Napierian or natural logarithm of the mode's amplitude). The red dashed lines are respectively the median of the tracked frequency and the fitted first order polynomial to the 'log' of the mode's ringdown.

Notice that monitoring 21 hours at 8192Hz resolution of 50 modes provide a huge ammount of data so here I only present a summary of the results, and this is also the reason why the plots shown are .png files.

The first order polynomial fitting of the ringdown was done using Matlab's 'polyfit' function which implements a least-squares minimization fitting. This function also provides an estimate of the covariance matrix of the fitted coeficients which is used to calculate the standard error or variance of the estimated coeficients for the linear fit of the log(Amp) ringdown. In particular only the slope of the fitted line is used to estimate Q = Pi * f0 / abs(slope_fit), where f0 is the median of the frequency tracked. The median of the tracked frequency has an observed uncertainty smaller than 1mHz which makes the Q relative uncertainty to be dominated by the slope fitting uncertainty as given by the covariance matrix of the fitted coefficients. Therefore the reported error on Q will be given by the uncertainty of the slope of the fit as:

(Delta(Q) / Q)^2 = (Delta(slope_fit) / abs(slope_fit))^2

Next I summarise the results in 4 columns (also on attached .txt files labelled 'Q_results_3Harm_1stFreq_2ndQ_3rdDeltaQ_4thEHresults' and ''Q_results_4Harm_1stFreq_2ndQ_3rdDeltaQ_4thEHresults); first is the mode frequency, second is my estimated Q, third is the estimated Q error, and 4th is Evan Hall's results from 22847 for comparison:

Mode frequency (Hz)          Q (line tracker)                Delta(Q)                Q_from_22847

1.0e+09 *
   0.000001456177151   1.055261277139490   0.000021679047341   1.060000000000000
   0.000001456842619   1.011674961643711   0.000024977780728   1.020000000000000
   0.000001461409317   0.547106388691582   0.000007012695846   0.550000000000000
   0.000001461732469   1.000243995219630   0.000121822842175   1.000000000000000
   0.000001461859533   0.673721968942594   0.000056781365996   0.644000000000000
   0.000001462031866   1.015448724742734   0.000039055044799   1.030000000000000
   0.000001462313302   1.109264503070151   0.000020406518349   1.120000000000000
   0.000001462596624   0.879503445780186   0.000090574514768   0.921000000000000
   0.000001463096689   0.881010088452959   0.000383879344618   0.995000000000000
   0.000001463100039   0.990987050813072   0.000431799209313                   0
   0.000001467475846   1.089361798635816   0.000107769329936   1.130000000000000
   0.000001467964869   0.979770107952095   0.000024671825593   1.000000000000000
   0.000001470380790   0.886560854120574   0.000042794470546   0.894000000000000
   0.000001470826225   1.046162403099169   0.000070957888675   1.040000000000000
   0.000001471928631   1.433692732321030   0.000246428147278   1.280000000000000
   0.000001472216373   1.036874013551553   0.000319968824557   1.070000000000000
   0.000001472450299   1.116249774693906   0.000012761989599   1.130000000000000
   0.000001474079863   1.178125176004288   0.000086507667346   1.170000000000000
   0.000001475097416   1.001120432026481   0.000377881305540   0.935000000000000
   0.000001475251394   1.148066981481587   0.000155330486516   1.160000000000000
   0.000001478169574   0.781717093501666   0.000095725814070   0.830000000000000
   0.000001482585386   0.865266831531971   0.000049369138115   0.879000000000000
   0.000001484077440   0.912365853159565   0.000100741959112   0.914000000000000
   0.000001484430000                                   0                                 0   0.796000000000000
   0.000001484525699   0.821953404180692   0.000053588794283   0.836000000000000
   0.000001484668763   1.396430023353472   0.000359948050123   1.270000000000000

   0.000001922925589   0.806732893457201   0.000050155023271   0.812000000000000
   0.000001923612098   0.904079503131098   0.000101465317927   0.856000000000000
   0.000001923854589   0.730146274074320   0.000057632970265   0.741000000000000
   0.000001923861257   1.045943198261562   0.000286910927180   1.000000000000000
   0.000001924673359   0.656777206317145   0.000037377872702   0.675000000000000
   0.000001924914736   0.822610665784300   0.000055143089987   0.845000000000000
   0.000001926240582   0.877913538609440   0.000041733066792   0.888000000000000
   0.000001927465534   1.193131464187697   0.000196087122798   1.080000000000000
   0.000001928461859   0.491982285283618   0.000060799517584                   0
   0.000001929312799   1.014511076625149   0.000491391979504   0.742000000000000
   0.000001931573475   0.770986524485489   0.000120874236513   0.778000000000000
   0.000001932139817   0.721080850064806   0.000077175334498   0.739000000000000
   0.000001932335653   0.723984558093199   0.000083370684684   0.713000000000000
   0.000001932612502   0.802178526483954   0.000016727734773   0.806000000000000
   0.000001940322842   0.727877169848855   0.000210139484624   0.778000000000000
   0.000001940663844   0.923330707711907   0.000027923601820   0.941000000000000
   0.000001941349656   0.922491569137019   0.000274707300452   0.906000000000000
   0.000001942174877   1.171274720414585   0.000377051759607   1.050000000000000
   0.000001942390477   1.094325186350570   0.000475289691312                   0
   0.000001943777687   0.914373092200222   0.000483429769721                   0
   0.000001946732789   0.732800137163962   0.000093031972218   0.677000000000000
   0.000001954459289   0.803950536039718   0.000153319383649                   0
   0.000001955921818   0.684755442755530   0.000143761779921                   0
   0.000001957335075   0.651607142944878   0.000091322052084                   0
   0.000001959023577   0.785016144699797   0.000093723756453                   0

NOTE: Although there are not big differences in results with entry 22847 for the 3rd harmonics, however some difference is observed on the Q's of 4th harmonics, also 7 more modes are reported here for the 4th harmonics.

I have turned off the violin mode damping filters for IX and IY by zeroing their gains. Patrick accepted these into SDF so that we can go to observing.

This is meant to be temporary, i.e., for this one lock only.

The next time the interferometer comes into lock, the Guardian will turn on the normal violin mode damping settings. These settings will appear as SDF diffs (two on IX, and six on IY). These should be accepted into SDF.

We do not expect these modes to ring up during the course of the lock. However, if the mode height on the control room DARM spectrum around 500 Hz rises above 10⁻¹⁶ m/rtHz, the damping should be turned back on:

1. Make sure the ramp times for the damping filter modules are at least a few seconds (currently they seem to be set to 10 s).
2. The filters should already be configured to provide the right damping phase, so changing the filters should not be necessary.
3. Start typing in gain settings. Refer to the values listed below. If the violin mode amplitude is much much higher than usual (e.g., it's off the scale on the control room DARM spectrum), it is wise to start with a small gain (e.g, gain of ±1) in order to make sure the suspension drive does not saturate. Then you can increase the gain in several steps, until the nominal setting is achieved.

A screenshot of the nominal IY damping settings is attached (I didn't take one for IX).

ITMX:

• MODE3 gain: −100
• MODE6 gain: +200
• all others zero

ITMY

• MODE1 gain: −200
• MODE2 gain: −200
• MODE3 gain: +100
• MODE4 gain: −50
• MODE5 gain: +400
• MODE6 gain: +50
• all others zero