At the request of Jameson, I had done the output HAMs on Monday and this morning I completed all the others.  None of the platforms were disturbed so this was completely non-invasive.  In general though, the restarted node switched to EXEC with a request of NONE.  Returning the mode to MANAGED and the request to whatever put things back with no fuss.  The Chamber manager typically lost communication with the subordinate but I always restarted it last and all finished in good shape.  I say "In general...and ...typically..." because the behaviour was not universally consistent.

no restarts reported. First day after memory increase in QFS writers.

Kiwmau, Alexa, Sheila

Tonight we were having difficultly keeping DRMI locked stably, so we decided to spend some time looking into it rather than continuing to try locking the arms +DRMI.

First we had a look at our ASC loops.  We copied the filters from the OMC QPD centering servos for the AS WFS centering servo, this keeps the beam centerd on the WFS much better.  We also had to use the picomotor to steer it a few times because we ran out of range wth OM2.  Sometimes our 4 DRMI ASC loop (AS A 45 Q to BS, REFL A 9I to PRM) worked, well, sometimes they did not.  We loked again for a signal to use for SRM, (they are using refl B 45 Q at livingston according to 13513)  So, far, all of the 45 signals have a large offset.  We haven't looked at 36, or AS B since we don't have AS B centered. 

We decided to try some TCS CO2 laser on ITMX to see if this would alleviate our mode hopping problem.  We tunred the CO2 laser on at 1 Watt.  We had DRMI locked with our 4 ASC loops working, however the buildup in DRMI degraded.  We then measured the contrast by locking mich on the dark fringe then the bright fringe.  32 minutes after we turned the laser on, the contrast was 97.8%, (worse than what Kiwamu measured 13824) it continued to get worse for the next ten minutes.  We then turned off the laser, and watched the contrast improve (kiwamu has the screenshot). 

We then looked at G1401119, to gues that we need about 370/572 of the laser power that livingston uses, ( 14673), so we set the power to 180 mW, according to H1:TCS-ITMX_CO2_LSRPWR_MTR_OUTPUT, which is a requested power of 0.12 and an angle of 45 degrees on the rotation stage.  (we set this at 8:09 UTC on october 16)

Here are some lockloss times for DRMI 2:51:29 UTC 2:57:07 (arms were locked with ALS)

DIFF 2:34:40 2and 2:37:20 UTC all of these times are october 16

Rick, Filiburto, Richard, Jim, Dave

During the PCAL install yesterday Rick was having problems driving DAC outputs through the 8 channel 18bit AI chassis. Today we put this chassis onto the DAQ Test Stand and verified that signals were indeed coming out of the front panel. However when we reinstalled the chassis at EX we discovered that channel 1 was being output as channel 5, 2 as 6 etc and channel 5 was outputing as channel 1 (basically the lower and upper blocks of four channels were reversed). Internally the filter board has two DB9 connectors, so this is where the 8 channels are divided into two sets of four. It would appear that the ribbon cables connecting the filter board to the input board are reversed judging by the cable lengths. We reversed the cables and this unit is ready for reinstall at EX.

We will discuss this issue tomorrow with Richard to see how we can proceed on getting the fix to all the 8 channel PEM/PCAL AI chassis. Note these are different from the SUS AI chassis which have 16 output channels and are driven by two DAC cards.

SudarshanK, TravisS, RickS

We moved the ETMY camera from the viewport above the Pcal input viewport to the viewport adjacent to the optical lever input port down at the bottom of the A1 adapter.

This location gives a more complete view of the ETM (less occluded by the Arm Cavity Baffle).

Fitting the camera can in that location required rotating it about 10 deg. due to interference with the OptLev sheet metal cover. The GigE camera was rotated to roughly orient the view such that the flat on the ETM is vertical.

An image of the ETM with the new camera view is attached below. 

Worked continued with installation of PCAL electronics at EX. All long field cabling were pulled in yesterday morning. This afternoon, we continued with dressing of cables and started installing DC power supplies.

Whitening chassis S1101631 was removed from the ISC-R1 rack this morning. Unit was found to have missing positive rail. Unit was replaced with new unit (Need to get serial number).

This aLog is a little postdated as this issue happened on October 11th. I was attempting to get calibration values for the rotation stage on the ITMx CO2 table, but I was seeing hardly any power from the laser. I should have been getting ~5w by the periscope and was only seeing ~1w. Power output directly out of the laser was reading ~20w during continuous wave operation but should have been >50w. Luckily the problem was found fairly quickly. The power cable on the outside of the table enclosure was not screwed in and the Connec connector had come partially out. Interestingly this had the effect of only partially supplying the RF driver and so the laser ran at a reduced capacity.

Day Shift Summary
LVEA is Laser Hazard
Observation Bit: Commissioning

09:15 Transition LVEA to Laser Safe. 
09:30 General LVEA post installation cleanup
09:55 US Linen on site to meet with Bubba G.
10:01 Ron - On site to visit Kyle for leak detector repair
10:25 Kyle – going to End-Y
10:39 Paradise Water on site
11:10 Filiberto – End-X top swap whiten chassis, and cleanup end station
11:30 LVEA cleanup completed
11:47 LVEA transitioned to Laser Hazard
13:25 Filiberto – End-X to work on PCal cabling
14:28 Rick – Going to End-X
14:55 Rich – Going to End-Y to mount camera
15:10 Dave & Jim – Going to End-X to check ISC chassis problem

With this valve open, only a single NW blank seal separates the VE (and beam tube with 44" gate valves open like current state) from atmosphere - Ouch!  Closing this valve after rough pumping is in the procedure but was missed, apparently.

Continuing from my previous  measurements Z/RZ, I took more measurements on ITMX, this time looking at X to Z and RZ. I don't have a lot to say, but I did notice an interesting feature, that may or may not be related to something Krishna has been noting. If you look at the X to Z transfer functions there is a bump at just above .1 hz. Every sensor sees ths bump, and it is there regardless of whether I am driving with HEPI or the ISI. I haven't had a chance to run this measurement on Y on this particular chamber yet, so I don't know if you see this when driving in all horizontal DOFs. The X to X and Y (last png) also look strange, especially the X to Y when driving on HEPI (solid blue), not sure what to make of it.

I've updated the OS on some of the PSL workstations to the latest CDS image - pslws0 and pslws3.  I tried to do pslws1,2 as well, but when I restarted them as a test, they decided to shutdown instead.  So they need to be booted the next time someone is in the PSL enclosure, then I can try again for those two.

J. Warner, K. Venkateswara

Using Jeff K.'s model modifications, we were able to incorporate BRS tilt-subtraction to the GND_STS which was then output to STS_C channel (which was empty previously). This was then used for sensor correction by changing the cartesian conversion matrix. The tilt subtraction filter uses a simple acceleration to velocity converter, a gain matching and a high-pass filter.

Rich M. wrote for us a neat IIR filter to try out for the sensor correction filter bank. After the first attempt doubled the ground signal, we used this with a gain of -1.0 which worked well :)

We wanted to try out this sensor correction yesterday, but there was a lot of activity at ETMX which was disturbing the BRS as shown in the attached .png file. The good news is that immediately after the activity ceased, the BRS output settled down so the damper continues to work as expected.

This morning we had some time to try it out before EX activity resumed. The file NoSensCorr45mHzblnd.pdf shows the current ISI stage 1 performance with the 45 mHz blend filter. As I've mentioned before, notice the nice coherence with the GND_STS_X and ST1 T240_X between 0.1 to 0.6 Hz. The Y-axis is in counts (velocity).

For the uninitiated, sensor correction adds the ground sensor signal to the position sensor, thus it is effective only below the onboard inertial sensor blend frequency. In this case, since we wanted to do sensor correction in the 0.1-0.5 Hz band, we shifted the inertial sensor blend to 250 mHz. The two files NoSensCorr250mHzblnd.pdf and SensCorrOn250mHzblnd.pdf shows the Stage 1 motion without and with sensor correction respectively. Even with sensor correction on, this configuration seems to be a factor 2-5 worse in the 0.1 to 0.5 Hz band, but it is very interesting that the coherence with GND_STS_X is much smaller. And there is significant coherence with ST1_T240_Z at the microseismic peak. This might be related to what I mentioned before in 14426.

But to our surprise we were injecting noise below 0.1 Hz. I then rechecked our tilt-subtraction filter and it turns out we had one filter gain wrong. I've corrected it and I verified that the tilt-subtracted super-sensor was indeed smaller than the ordinary ground sensor. Unfortunately, EX activity resumed just then and we couldn't verify that the sensor correction was lowering the noise below 0.1 Hz. The ISIs were restored to the 45 mHz blends for commissioning activity.

Summary: Our first attempt at trying sensor correction with the ground 'super-sensor' was not terrible! :) We will do a more refined attempt tomorrow. We will also try doing sensor correction using HEPI which may give slightly different results.

re my 14425 aLOG Monday, this morning I indeed found the STS2 B misoriented; this is the unit in the beer garden.  Just as I suspected given the individual HEPI sensors' coherence with the X & Y signals, the X axis of the STS2 was ~-45degrees from our desired X axis.  I say ~ because we don't have a mess of X Y grid lines all over the floor.

I also found the level of the STS2 to be quite poor--the bubble was railed.  This might have been leveled upon installation, not sure when that was, but maybe the heavy instruments (55lbs) slowly differentially sinks into the vinyl floor.  Maybe the floor should be accessed to put the feet directly onto the concrete.  At least, I should look at it again in a week or something to check for tilting.

So I rotated the STS2 to align its X alignment point to be parallel with the X arm and then leveled the bubble.

I 'autoz'd the machine now several times but some axes still have relatively large values.  It may be suffering now from some thermal drift as the igloo must be removed to do the level and alignment.  We may need to rezero daily for a few or even several days.

Attached is a repeat of the measurement I posted log 14425 and as expected, now the X & Y conputed signals are strangly coherent with the STS2 X & Y outputs.  And, I think it makes sense, the 4 local HEPI sensors all have about the same marginal coherence to the ground sensor signals.

Now back where I started Monday, looking at the coherence between the ground STS2 and the HEPI L4Cs.  It is very strong between 0.15 and 4hz.  It falls pretty rapidly starting about 0.15hz and above 4hz.

model restarts logged for Tue 14/Oct/2014
2014_10_14 09:29 h1isietmx
2014_10_14 09:35 h1broadcast0
2014_10_14 09:35 h1dc0
2014_10_14 09:35 h1fw0
2014_10_14 09:35 h1fw1
2014_10_14 09:35 h1nds0
2014_10_14 09:35 h1nds1
2014_10_14 09:42 h1calex
2014_10_14 09:53 h1pemex
2014_10_14 09:54 h1calex
2014_10_14 09:58 h1pemey
2014_10_14 10:01 h1caley
2014_10_14 10:01 h1pemey
2014_10_14 10:03 h1broadcast0
2014_10_14 10:03 h1dc0
2014_10_14 10:03 h1fw0
2014_10_14 10:03 h1fw1
2014_10_14 10:03 h1nds0
2014_10_14 10:03 h1nds1
2014_10_14 11:49 h1fw0
2014_10_14 11:49 h1nds0
2014_10_14 11:54 h1calex
2014_10_14 11:54 h1pemex
2014_10_14 12:05 h1caley
2014_10_14 12:06 h1pemey
2014_10_14 12:31 h1fw1
2014_10_14 12:32 h1nds1
2014_10_14 12:35 h1broadcast0
2014_10_14 12:35 h1dc0
2014_10_14 12:35 h1fw0
2014_10_14 12:35 h1fw1
2014_10_14 12:35 h1nds0
2014_10_14 12:35 h1nds1

no unexpected restarts. Maintenance day. ISI ETMX, PCAL and DAQ work. Some DAQ restarts to support model work.

model restarts logged for Mon 13/Oct/2014
2014_10_13 02:52 h1fw1
2014_10_13 11:12 h1iopsush56
2014_10_13 11:12 h1susomc
2014_10_13 11:12 h1sussr3
2014_10_13 11:12 h1sussrm

unexpected restart of fw1. Power cycle of h1sush56 for 70Hz noise hunting.

Seismic: Would like to do a Guardian restart. Continuing seismic commissioning
Commissioning: Stand down in morning during Laser safe in LVEA during cleanup 
TCS: Packing up 3IFO parts
PCal: Wiring at End-X 
3IFO: Inventory work at both Mid-Stations
All: General post installation cleanup in LVEA 

For the records, and in order for us to define new threshold values, I am posting here the pressure fluctuations for all the BSC-ISI pods (L4C, GS13 and T240), for all units on both sites (I will link this to the LLO log).

The first table attached shows the variations of pressure and the average leak rates for LHO. The L4C varies more than the GS13. The T240 pressure readout is pretty much the same than six months ago.

In this sample of data, we observe larger fluctuations at LLO than LHO, in all pods. The variations are however very similar within all the pods of a given chamber. So it is likely temperature related.

The last table compares the average variations and apparent leak rate for both sites.

With the microseism being elevated over the weekend--looked at the floor seismo wrt the HEPI L4Cs.  We'd really like to help with microseism noise but it is a tough problem.  However, something just doesn't seem right.

Looked at coherence between the floor sts2 and BS HEPI X Y Z Blend inputs.  Strong coherence with Z but X & Y pretty poor.  Looking at the locally oriented sensors and whoa, strong coherence with the diagonally oriented HEPI L4Cs split between the X & Y...  See attached.

The upper left panel has the coherence with the cartesian basis blend inputs.  Strong in Z but oor in X & Y.  The lower left panel  has the local basis horizontals with the X ground signal: Strong in H1 and H3, the sensors oriented NE to SW (building crane basis.)  The H2 & H4 sensors, oriented Nw to SE show little to no coherence.  The upper right panel looks at the horizontal local sensors wrt the Y ground motion and the result is the opposite: strong signal with the H2 & H4 L4C but little to none in the H1 & H3 signals.  The lower right shows the strong coherence in all the Z local L4C signals with the Z signal from the floor seismometer.

Since the Z signal has good coherence, I don't think there is any problem with the model path, maybe?

Since the Local to Cartesian transformation has equal magnitudes (the local sensors are oriented at 45 degrees to the LIGO referencef frame, I don't believe the matrices are to blame. These values are correct based on T1000388.

This leads me to conclude the the ground STS2 must be oriented incorrecty or its internal U V W transformation to X Y Z is messed up.  This will certainly cause issues with sensor correction etc.