CDS model and DAQ restart report, Thursday-Sunday 18th-28th February 2016

Friday 26th - Sunday 28th No restarts reported

model restarts logged for Thu 25/Feb/2016
2016_02_25 12:41 h1iopsusauxh2
2016_02_25 12:41 h1susauxh2

Following h1boot NFS problems, rebooted one system to verify front ends could boot.

Tuesday 23rd - Wednesday 24th No restarts reported

model restarts logged for Mon 22/Feb/2016
2016_02_22 13:23 h1ascimc
2016_02_22 13:23 h1lsc
2016_02_22 13:28 h1broadcast0
2016_02_22 13:28 h1dc0
2016_02_22 13:28 h1nds0
2016_02_22 13:28 h1nds1
2016_02_22 13:28 h1tw1
2016_02_22 13:29 h1nds0

Early maintenance day. ASC and LSC code change and associated DAQ restart.

Thursday 18th - Sunday 21st No restarts reported

XARM IR locking slightly better

Matt, Sheila, Cheryl

This morning the XARM wouldn't lock in IR, this is a pesky problem that has come and gone.  It seems like the problem was that both the bounce and roll modes of MC2 were rung up.  We added resonant gains in MC2 MS ISCINF that will be used durring arm IR locking only (there are already notches in M2 that are always on).  We also turned up the gain a bit to put us near the high side of the gain bubble when well aligned.  

IM2 (PMMT1) oscillating after Satellite module fix

IM2 position is now oscillating by 5urad in pitch and yaw after satellite module fix on Feb. 23.

Three plots attached:

• Time series showing it working briefly then going into oscillation
• power spectrum of all IM2 OSEM inputs - high res, 0-7000Hz
• power spectrum of all IM2 OSEM slow channels - 0-100Hz, showing a 10Hz comb

Start copy of trend files from h1tw1, restart h1nds1 with new configuration

WP 5747

I have started copying raw minute trend files from h1tw1:/trend to h1fw1:/frames.  This is a period maintenance task that is performed every 5 to 6 months.

I also reconfigured h1nds1 to read the trend files for the last 5 months which were moved temporarily to allow copying.  The h1nds1 has been restarted to allow access to the complete set of trend files.

IFO_ALIGN.adl

I've finished adding  yellow boxes around the DC sliders on the IFO_ALIGN SCREEN for all the suspensions to indicate when values are ramping as per Sheila's request. I tested some of it successfully. Please take note of any weirdness and report it to me.

Thanks

PSL Weekly 10 day trends

Listed below are the past 10 day trends. For further in-depth analysis, please refer to Jason O., Pete K. or Rick S. 

Optical Lever 7 Day Trends

Attached are 7 day pitch, yaw, and sum trends for all active H1 optical levers.

Monday Morning: status and plans for Maintenance

H1 status:

- CP3 short is gone, final configuration ongoing

- no crane work in the LVEA scheduled for Tuesday

- beam tube enclosure sealing continues

- staging building alarm is coming in on the fire panel

    ---feel free to acknowledge, not a fire concern

 

Tomorrow's Maintenance:

- Richard - ITMs and BS satellite amp upgrades, possibly more

- Richard - CPS timing RF cables at end stations

- JeffB - monthly envi. checks

- Kyle - VEA laser safe for soldering, 

- JeffK - commit models to SVN

- Hugh - HAM4 and HAM5 model corrections

- TJ - bounce and roll guardian roll state

- TJ - psl guardian

Looking for SRC back-reflected beams on ETMY baffles.

Still chasing the SRC gouy phase.  On Saturday I was looking for the beam reflected back from the SRM through the SRC, transmitted through the ITM towards the ETM.  I was trying to see the beams on the ETM baffles.  The bottom line is that after trying to move multiple optics including BS, ITMY, SR3, SRM, I was not able to see any beam on the ETM baffle PDs except for the propt reflection from the BS towards ETMY (which doesnt travel through the SRC).

Method:

ITMx, ETMx, ETMy, PRM were misaligned for this measurement.  To split the beams travelling through the SRC an optic in the SRC must be misaligned.  I could look at the beams on gige cameras ASair and cam17 and the analogue camera looking at  Ham 5.  I saw no beams on the ETMy gige camera, is this working currently?The baffle Pds are 35cm or 3 beam diameters apart, so was aiming the split the prompt reflection from the BS to ETMy from the beam that travels once through the SRC by at least 1.5 beam diameters.

First tried moving single optic, eg BS or SR3, by applying excitaions of different frequencies in pitch and yaw, and then looking for a signal on the baffle PDs.  I saw no signal that was not the prompt reflection, which was present whther or not the SRM was aligned. ThenI tried moving BS to center the prompt reflected beam onto a baffle PD, moving it slightly off to the side and then moving the and moving SRC optics with an excitaion in pitch and yaw, one at a time.

  Then tried moving SRC/ITMY optics, with no BS misalignment.  I saw no beams on the baffle PDs when moving the SRC optics, anr only the prompt reflection when moving the ITM and the BS.

 

I could see a beam inside the SRC on the SR3 baffle, which I think was the second trip around the SRC.  So I think the first trip around the SRC was making it through the ITM and it wasn't clipped, but I couldn't get it on the ETMy baffle.

 

As a side note:

Funnily enough, while doing this misalignment business I noticed three beams on the gige camera 'cam_17'  on ISCT_6.  I think these is the straight shot, the one round-trip and two-round trip beams through the SRC. The angle between these beams also tells us the SRC gouy phase.  Stefan and I tried to look at these beams last year on the AS_air camera with no success, and we concluded that we couldn't split these beams without clipping on an optic.  But the cam_17 is a new camera in a different part of the AS_air beam waist.  And it looks like we are seeing all three beams.  Interesting.

0.5Hz Comb Investigation Update

Vinny, Brynley

Over the past 2 weeks, we used a temporary magnetometer in the CS CER and the EY CER and computer racks. We placed the magnetometer in a range of locations, and created spectra from the magnetometer at each. It had been mentioned that the timing slave card in various chassis might be the cause - as an LED with a 2 second period is fitted on each. To that end, after a first study, our follow up was aimed at those chassis with timing slave cards.

The first spectral plot attached shows spectra from the EY CER.  All of the traces are near the noise floor because we were not using the typical magnetometer filter box, which applies a gain of 100 above 1 Hz.  Despite this the combs are easily and increasingly visible as the magnetometer gets closer to the timing racks.  Each trace is made with 170 averages of .1875 Hz resolution FFTs.

The second plot shows spectra from the corner station CER.  This time we used an SR560 pre-amplifier to get our gain of 100 above 1 Hz.  Once again the comb was stronger as the magnetometer got closer to the timing racks.  Once again each trace is made from 170 averages of .1875 Hz resolution FFTs.

The third figure shows the spectra taken from the CER at EY. We used the SR560 to apply gain of 100 above 1Hz. For this plot, the magnetometer was placed near to a number of instruments, some with timing slave cards, and some without.  EY's TCS-1 rack RF oscillator source. The 0.5Hz combs are very strongly visible throughout the signal. The trace is made from 15 minutes of data, with 0.03125Hz resolution

The fourth plot is a short segment of the magnetometer's time series associated with the spectrum in the third plot. The magnetometer was placed near to the  Timing Slave card on EY's TSC-TRF Oscillator source. The time series shows that on second boundaries, the magnetometer sees a large field, quickly dieing away. No post-processing or filtering has been performed on this time series.

There has been no "Observing" data during these investigations, but the detector had "DC Lock" from Feb. 20 04:00 - Feb 20 12:00 .  The last image is a oherence plot (between H1:LSC-DARM_IN1_DQ and H1:PEM-CS_ADC_4_28_OUT_DQ) made from those 8 hours of data.  64 second FFTs, 899 averages.  The comb is clearly visible, confirming that this is the comb appearing in DARM.

NOTE: To clarify, at EY, we temporarily usurped on the PEM TILT X channel for our magnetometer. The plots which show the TILT are in fact our temporary magnetometer. BP 02/29/2016

Manually over-filled CP3 at 23:20 utc

1/2 open LLCV bypass valve, and the exhaust bypass valve fully open. Flow was noted after 2.5 minutes, closed LLCV valve, and 3 minutes later the exhaust bypass valve was closed. Next over-fill on Tuesday, March 1st before 23:59 utc.

preliminary results from OMC DCPD cross spectrum analysis for entire O1 run

I have extended the cross spectrum analysis (see 25009 and its comments) to the entire O1 run.

Preliminary conclusions are that:

• Noise in 80 -160 Hz seem to have fluctuated by about +/- 20%.
• Noise in 80 -160 Hz seem to have kept the same spectral color.

I will dig into some interesting days or periods and study how different things were.

---

[Setting up band limited rms]

To analyze the cross spectrum as a function of time, I decide not to do spectrogram type analysis which may contain too much information. Rather I wanted to study the time evolution of the band limited rms. This approach is very similar to what Gabriele does (e.g. 22514).

I selected eight interesting bands in which I avoided tall peaks in the spectrum because I am not interested in their amplitudes in this study. The attached below shows the eight selected frequency bands.

The frequency bands are chosen as follows,  Band 1 = [20 25], Band 2 = [30 35], Band 3 = [50 55], Band 4 = [81 95], Band 5 = [101 110], Band 6 = [121 126], Band 7 = [130 140] and Band 8 =[150 156].

[Time-varying calibration parameters are corrected]

I have corrected for all kappas, the time varying calibration parameters, by applying them to the H1 DARM model of the calibration group. Since one cross spectrum is produced from a twelve minutes integration, kappas are also averaged for twelve minutes. Therefore, the data sets that I analyzed here must be less sensitive to calibration errors due to the time varying parameters which can deviate roughly by 10% from the reference values.

[Glitches and transients are removed]

I have removed data segments that were contaminated by some glitches or transients because I am not interested in their characteristics. This was done by computing an average Rayleigh static over the frequency range from 60 to 100 Hz and rejecting the segment which had a Rayleigh statistic deviating from unity by more than 10%. So the data set I analyze here has more or less good Gaussianity.

[Result 1: time evolution]

The attached plot below shows the band limited rms of the selected eight frequency bands as a function of time in days starting from Sep-01 00:00:00 UTC.

Typically, the two lowest bands (band 1 and band 2) vary more than the others presumably due to the fact that they can be easily degraded by seismic activities, alignment loop and LSC feedforward. In contrast, the rest of high frequency bands (bands 3 -8) are more stable but still do fluctuate. Notice that the high frequency bands decreased their rms at t = 50 days or so. I believe that this is due to Robert's improvement of reducing the PSL jitter coupling (22497). Also, one can find many interesting periods where one of the bands increased the displacement while the rest stayed unchanged and so on. I will try to check those interesting days later.

The fluctuation of the four highest bands (bands 5 -8) are at 15-20 % level (or 30-40 % in peak to peak) with high sigma data points excluded.

By they way, I forgot to multiply sqrt(df) with df being the frequency resolution to all the band limited rms . The frequency resolution df is currently 0.1 and therefore all the data shown in the above plot should be lowered by a factor of sqrt(0.1) = 0.3. This does not change the main conlusions.

[Result 2: behavior of the high frequency bands]

Now, the plot below shows a primitive correlation plot.

where the horizontal axis represents the displacement of band 8 and the vertical axis is for the rest of the bands in order to show correlation with band 8. I have excluded the first 50 days in which the high frequency noise was higher due to the PSL jitter coupling. By the way, the x-axis is in log scale although it may look linear to some people. As seen in the plot, bands 4-7 show a positive correlation with band 8. Also their slopes seem to be identical. These indicate that noise level above 80 Hz fluctuate in such a way that it keeps the same spectral color. As mentioned above, the size of fluctuation is about 15-20% for bands 4-8.

All the data in the above plot should be lowered by a factor of 0.3 for the same reason as the time series plot . This does not change the main conlusions.

OPS Eve Shift Summary

TITLE: 2/27 eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
QUICK SUMMARY: The environment was friendly today, Sheila and Evan are working their magic, and the alarm in the computer users room has only gone off twice since Richard left for the day.
 

Ringdowns of violin-mode first harmonics

reservation system decrementing program running on script0

The program which decrements the open reservations was on a machine which was recently decommissioned. It is now running on script0 as user controls under a screen environment.

Y-arm HWS aligned and new problem with X-arm HWS beam

[Kiwamu, Elli, Nutsinee, Cao]

We attempted to align the SLED beam onto the Y-arm HWS today. We scanned the SR3 in both pitch and yaw and identify three beam spots. Two spots could be obseved while scanning in yaw and in pitch. One of them was a common spot. The two spots were separated by 800 micro-radians.

           PITCH: To identify two spots in PITCH, use wedge angle of ITMY: vertical wedge with angle of .07 degrees.    Thus ITMy causes beams to separate in vertical direction

                  Increasing pitch of ITMY leads to moving both vertically separtated spots move upward, which implies that the beam reflected off the HR surface is vertically below the beam reflected off the R surface.

                  This was re-confirmed by scanning the SR3. We noticed that the beam identified as the HR beam occurs consistently at 800 mico-radians below the AR beam.

           YAW: To identify  two spots in YAW, we turned the CO2 lasr on and apply 4W power to observe change in spherical power measured by the HWS. The spherical power only changes for the beam spot at lower SR3 yaw value. The only issue theat occurs was that when compared to simulation, the changes is in the opposite sign.  But we are sure that this the right beam spot, which is surpringly the beam spot at the beginning

We then walk the SR3 to nominal value and performed fine adjustment of the picometer to centre the beam spot on the y-arm HWS.

We then check the X-arm HWS, this is where new problem arises. After scaning the SR3 both in pitch and yaw, we optimise to centre the X SLED beam on the HWS. Despite this, the image streamed from the X-HWS shows a beam with lower intensity, as compared to Y arm HWS beam. The Gaussian beam profile is also not clearly visible. We performed a CO2 laser test again and observed spherical power measured by the X-HWS. The results shows that the spherical power value is very noisy and doesn't have an apparent trend hat it is supposed to have as the CO2 laser is on.

Moved OMC dither frequency by 0.21 Hz, 16 Hz comb on PZT1

Today Keita and I spent some time thinking about OMC length noise, there will be an update coming soon with more information and a noise projection.  

We spent some time looking at some nonlinear behavoir noise in the drive to PZT1.  Our dither frequency is 4100 Hz, and looking at the low voltage PZT monitor we can see a small 8 Hz and a larger 16 Hz comb.  There is also other non stationary noise in the monitor, and a broad peak at 12.7 kHz.  We have moved the dither line frequency to 4100.21 Hz, so if this was the cause of the 16 Hz comb in DARM we would now expect it to be more like a 16.84 Hz comb.  Evan Goetz tells us that we need 15 minutes or more of data in low noise to evaluate if this has changed any combs in DARM. 

We have just reached nominal low noise at 3:14:34 UTC Feb 25th, although the low frequency noise (below 50 Hz) is worse than normal.  I've temporarily changed the dither frequency in the OMC guardian, so if there is a longer lock later tonight it should also have this changed dither frequency.    (If anyone wants to double check what the dither frequency is, the channel is   H1:OMC-LSC_OSC_FREQ

 

 

To quote Bill Murray in Groundhog Day, "Anything different is good." (at least in this context)

The 16-Hz comb does indeed appear to have changed into a 16.84-Hz comb. 
A DARM spectrum from two hours (400-sec coherence time) last night in the 150-250 Hz band is
attached, along with one from January on a day when the 16-Hz comb
was strong. New lines are seen in this band at

151.56 Hz
168.40 Hz
185.24 Hz
202.08 Hz
218.92 Hz
235.76 Hz

Some 1-Hz zooms are shown for a couple of the new lines.

So...can we fix this problem?

Splendid -- no 16-Hz or 16.84-Hz comb seen in a 2-hour stretch from last night!

See attached spectrum 150-250 Hz spectrum for comparison
with above plots, along with 0-1000 Hz spectra from last night
and from the night before, with the 16.84-comb present.

Many thanks from the CW group as we look ahead to O2.

Sheila pointed out that the noise floor for the 2nd spectrum
is considerably higher than for the 1st and could be hiding
residual lines due to the dither. So I tried shifting the 2-hour 
time window a half hour earlier, to avoid the hellacious glitch
seen in the inspiral range (see 1st figure) near the end of
the original Feb 26 interval. The 2nd figure shows the resulting
spectrum with a noise floor closer to that on Feb 25. The
16.84-Hz comb still does not appear. 

So I think it's safe to say that the 100 times multiplication / divide
trick did indeed suppress the 16.84 Hz (originally 16 Hz) comb a
great deal, but of course, we will need long coherence times and
long integrations to see if what's left causes residual trouble for CW searches.