Seems like somebody rebooted things and didn't burtrestore h2sustmsyepics.

Left YBM turbo header purge valve cracked open a little -> need to remember to close this before pumping next week

- HAM6 set, dust counts being watched (even as dust monitors are rebooted by Patrick
- Apollo using dirty room for degrouting/drilling of HAM5
- Erecting H1-Electronics Mezzanine Storage
- Instrument Air being used by GV6 and GV8
- Venting Y-Beam Manifold swapping flange out
- EY: Testing to find rubbing
- TMS: Looking for replacement cable, Time Domain Reflectometer
- Ken working on instrument wiring at H1 PSL
- H1 PSL fan units may come today (Friday)
- SEI - set elevations of HAM1 support tubes

Betsy B., Jeff G.

The UIM (L1) LL OSEM flag was suspected of rubbing, so Betsy and I set out to make real-time adjustments/measurements.  The first attachment is the final measurement after about 4 or 5 individual measurements taken between OSEM flag adjustments.  The UIM LL OSEM flag was taken out completely from the LED beam path, remeasured, then re-seated in the beam path.  
 The extra resonances between 1-3Hz in the L to L TF (red trace) have been mostly remedied, although there is still notable Long. to Pitch coupling.  The second attachment is a tuned matlab TF measurement of the Long. to Long. taken a day earlier with added resonances between 1-3Hz on the M0 mass, which was the motivation behind yesterday's investigations. The Long. to Long. measurements are much better after re-seating the flag.  More thorough matlab measurements will be run this afternoon to diagnose the remaining DoFs.

Before commissioning starts on ISI-BSC8 next week, the tests and control work realized so far are reported in:
- E1100845-v3: aLIGO BSC-ISI, LHO Unit #1: Phase II Testing Report (Integration)
- E1100294-v2: aLIGO BSC-ISI, LHO Unit #1: Phase I Testing Report (Assembly Validation)

A previous post detailed the new controls that were added to the BSC-ISI master model. These included feed forward (all DOF) and sensor correction (XYZ) from the HEPI L4Cs to BSC-ISI Stage 1, feed forward (all DOF) from BSC-ISI Stage 1 to Stage 2 using a blend of the Stage 1 T240s and L4Cs, and sensor correction (XYZ) from Stage 1 to Stage 2 using the Stage 1 T240s. 

Other things added to the master model include the GUARD block for guardian development and band-limited RMS filters (BLRMS) that use the Stage 1 T240s and Stage 2 GS13s to calculate the motion of the platform and normalize it on a log scale to the Advanced LIGO requirement. Vincent has wisely added a measurement indicator variable to the top level of the model, so I have added a blinking light to the overview screen to indicate when a measurement is in progress.

I've attached two screenshots of the new overview screens to this post. Some concern has been expressed that the screens are too small for the large monitors in the control room, and I am happy to develop a larger version of the screen if more people echo this sentiment.

We have also changed the macro inheritance variables that the seismic MEDM screens use. The variables should now be as follows: 
SITE=LHO,
site=lho,
IFO=H2,
ifo=h2,
CHAMBER=ITMY,
chamber=itmy,
IOP=H2IOPSEIB8,
iop=h2iopseib8,
USERAPPS_DIR=/opt/rtcds/userapps/release,
DCU_ID=75
From these variables, all necessary paths should be available to the user.

We are continuing to determine why sharing ADCs between models is weird.

While attempting to add the ADC with the HEPI L4Cs into the BSC-ISI model, we discovered that the signals in both models were not the same - that is to say that the signal received on the same channel and on the same ADC was different between the two models. The signals differ by a somewhat constant factor: the transfer function from one signal on the HEPI model to the same signal on the BSC-ISI model is mostly flat, with a light upturn or downturn at much higher frequencies, and with a certain factor difference that is usually a factor of 2.8 or 1/2.8 (that is to say that the signals are highly coherent, but the amplitudes are different, as if the signal from one was scaled by a certain gain relative to the other). Some signals did match, but the transfer function was not EXACTLY one, as it should be for the exact same signal (there were small deviations from 1 at high frequencies).

Since the models are running at different rates, we tried re-compiling the HEPI model at 4k to match the seismic rate. This changed which channels matched  between the two models, but there were still some un-matched channels between the two. 

We are still investigating the source of the problem. In the meantime, the isi2stagemaster model, as well as the individual h2isiitmy and h2hpiitmy models have been checked into the svn should anyone want to look for potential "We've measured the speed of light and it's off by 60 nano-seconds because there's a loose cable" type problems. We've already found one and corrected it, but that certainly doesn't mean there aren't others.

Hoping to get some good quiet time with H2 SUS ITMY after the chamber has finally been pumped down to a few x 10^-7 Torr, I took a quick glance at the OSEM alignment after noticing that M0 Damping loops were not on. Attached are screen shots of the OSEM alignment speedometers; they show that the Vertical/Roll sensors (M0/R0 LF and RT) have either lost their signal, or the flags are occulting the the LED/PD. M0's LF and RT are showing basically ADC noise and "off the radar," R0's LF and RT are at least on the radar (and should still be usable).

As such, I've left the system in a state where 
M0 L, T, P, and Y are damped
R0 L, T, V, R, P, Y are damped
and from my quick glances at BSC 8 ISI and BSC8 HEPI overview screens, I see that
HEPI is OFF
ST1 and ST2 Damping is ON

One can consider this state to be the case starting at
1014738296
Mar 02 2012 15:44:41 UTC

(and should true for at least another hour.)

Attached are plots of dust counts > .5 microns. The counts in the LVEA seem high.

(follow-up on previous mentions) 
Using a "feeler" gauge I measured the "gap" on the feed-through flange previously discussed which I was concerned may eventually leak due to (possible) bottomed-out flange screws.  The gap was 0.004".  These flange bolts seemed bottomed-out in their blind holes and I was concerned that I would strip the threads or break the screws if I continued to torque them -> knowing that we were venting anyway to fix the 2 x 10-7 torr*L/sec leaking triax feed-through, I went ahead and "stood on the wrench" and was able to close the 0.004" gap on this feed-through flange -> I leak tested this flange afterwards and it still didn't leak.  I don't know why this felt sooo... different than normal-perhaps the gasket was full-hard and didn't get tempered for some reason?  Slightly out-of-round?

I "fire hose" sprayed helium on all of the metal joints on the YBM to see if I could get any response other than the known leaking feed-through on BSC8.  I found nothing -> We'll vent tomorrow and replace the leaking triax feed-through flange.  Some evidence suggests that GV1's gate annulus volume might leak into the YBM -> I pumped it with an aux. cart but didn't note the time line unfortunately.  

Also, I soft-closed GV6 and opened GV5 to allow me to leak test the joints between these two valves -> I found a small (1.3 x 10-8 torr*L/sec) leak on GV6's lead-screw nipple CF joint(s) but this size of leak is smaller than I was expecting -> we might "bag" these joints in the future or maybe check the calibration of PT-114 and PT-124 in an attempt to explain their apparent discrepancy in this pumping configuration.

Hunting for the ETMy rubbing source, I removed the UIM (L2) LL Flag from the BOSEM (one of the last suspects).  Garcia ran a quick TF and observed that the mystery peaks were gone.  I replaced the flag, and the peaks still were vacant from a subsequent TF.  We then tweaked the alignment of the UIM UR flag since it was still a bit out and ran another quick TF.  Still no extra peaks.  Garcia is now going to run longer sets - hopefully the mystery peaks were just from the LL UIM flag brushing prior to this afternoon.

The default version of epics for the Mac OS X workstations has been changed to version 3.14.12.2.  This was done to allow more applications to be run on iMac workstations.  

In particular, StripTool now works properly on Mac OS X.  

This does affect medm as well, although no differences in functionality should be seen.

AFter attempting to get ahold of SEI testing people for a while this morning (phone calls, alogs, emails came up empty handed), we finally went to diagnose the ETMy rubbing at 10:15am.  This tripped the watchdogs and apparently the SEI measurements that were running.  Once we did hear word that we had stopped the measurement we stopped our work, waited for more word, then left.  Still waiting to hear what to do.  Is SEI restarting measurements, or now that they are killed should we continue our work??

200W beam

Yesterday Rick and I fixed swapped out a broken fitting on the diode chiller line to fix a water leak. PSL was brought back up after this, but ILS would not lock. Reference value for the PZT was changed from -1.65 to -1.40. The laser locked immediately, and has been running since then.

Fabrice, Hugo,

A GS13 huddle test was performed in order to pursue the investigation of the gain difference observed on the TFs measured on HAM-ISI Unit#2 (alog #2308)

Three horizontal GS13s were tested on the “bench”

• Pod #94, Production

Initially installed on this unit. Gain is half too small. One of its two op-amp could be malfunctioning.

• Pod #71, Production Spare

Response lower by a factor of 100 to 10000 below 20Hz. The seismic mass can be felt/heard when tilting the instrument, hence it is not stuck. The instrument will be opened at LHO for inspection. It will have to go back to LLO to pass the leak-checking-test before being installed on a Unit.   

• Pod #66: Test instrument

Locked test-mass got unlocked after manipulation. Acceptable power-spectrum. Not vacuum-compatible.

Conclusion:

Production GS13s are malfunctioning. The Test GS13 Pod #66 will be used temporarily for this testing phase of HAM-ISI Unit #2 testing. It will be removed before storage of the unit. Later on, a production GS13 will be installed for the side-chamber testing.