LVEA: Laser Safe

Gerardo and Kyle at working EY VEA
Mike R working in H2-PSL
Cyrus testing cables and install wireless AP at EX
Pablo working with Mike R. in H1-PSL. They are switching in and out of Laser Hazard inside the H1-PSL
Gerardo and Kyle working on GV-5
Hugh and Greg working on HEPI on BSC1 and BCS2
Jax at EY gathering up circuit boards for modifications
Apollo working on Op-Lev Pier anchors at EY
Mike R working in H1-PSL
Dave & Jim replacing pump controller at EY
16:04 Shelia transition EY to Laser Hazard  

Ear Bonding of ETM08 was aborted after finding precipitates inside Sodium Silicate Solution bottles, I contacted manufacturer and was told items had expired.  Norna was notified and bonding was suspended, new solution is on its way to LHO, bonding will resume next week.

(Danny S, Gerardo M)

ETM08 cake tin was opened  this week, Danny and I inspected the optic, and we found it very dirty, lots of particulate and some sort of "water spots/marks" are present on the optic's barrel.  Attached are some photos of the ETM08.  Water like "spots/marks" are present only on the barrel, more pronounced towards the bottom of the optic.

I performed a port scan on the H1 FE network, and at the same time the DAQ-DMT broadcaster program died and restarted. The other DAQ systems (frame writer, etc.) did not stop running. I will test this again next Tuesday.

(Kyle, Gerardo)

Removed and replaced the ion pump body from the annulus system at GV5.  Aux vacuum cart is pumping down the annulus system now.

The path to atmosphere via the broken weld in the regeneration circuit allowed a parallel path of exhaust to flow in this circuit (plumbing path).  The most recent fill of CP5's dewar combined with the PID reaction to this fill resulted in excessive vapor pressure above the pump liquid level which was sufficient to raise the liquid level in the regeneration line above its highest elevation.  This established a siphon of liquid which spilled out through the broken weld.  This is the only scenario where the indicated LN2 level in the pump could be < over full and for LN2 to be spewing onto the ground (another missed clue was the fact that LN2 was not evident in the exhaust line as would be required for my initial theory of the overall system being "over full".  

Gerardo and I removed a section of plumbing from the regeneration circuit which allowed as to "cap" this circuit and prevent future incidents of the this type.  

NOTE: 
All of the ambient air vaporizers on the X-arm are broken in this same place and will need to either be capped or re-welded (i.e., fixed) at some point.
 

I have changed the DC biases on M1s of MC2 and MC3 yesterday for getting a good alignment of the IMC.

Since the IMC was needed to be locked for a short period I just tweaked the two suspensions as this is relatively easy and quick to get a good alignment.

Here are the suspension biases on M1 of MC2 and MC3 before and after my adjustment:

/****   BEFORE  (PAST VALUES) *****************************************/

H1:SUS-MC2_M1_OPTICALIGN_Y_OFFSET  =  239

H1:SUS-MC2_M1_OPTICALIGN_P_OFFSET  =  407

H1:SUS-MC3_M1_OPTICALIGN_Y_OFFSET  =  -1024

H1:SUS-MC3_M1_OPTICALIGN_P_OFFSET  =  287

/****  AFTER (CURRENT VALUES)   *****************************************/

H1:SUS-MC2_M1_OPTICALIGN_Y_OFFSET  =  240

H1:SUS-MC2_M1_OPTICALIGN_P_OFFSET  =  447

H1:SUS-MC3_M1_OPTICALIGN_Y_OFFSET  =  -1006

H1:SUS-MC3_M1_OPTICALIGN_P_OFFSET  =  224

Had to break for a meeting.  Got the first IPS changed(Horiz) on the Actuator.  Will replace the Vert and the Pod after lunch.  Meanwhile Pier4 is also offline as the power to it comes from Pier3.

I have renamed several old versions of software to end with the name "to_be_removed".  Hopefully this will cause any software packages that are linked against them, or paths that point to them, to be exposed over the next week or so.  If nothing breaks, these will be removed in about a week.  If some other software does depend on them, we will recompile to use current versions.

Applied Clean all (don't save configuration) and rebuild all to all PLC project.

Rescaned all PLC projects.

Activated new system configuration.

Created new boot projects.

Reactivated system configuration.

Open OPC configurator and saved/activated it.

Restarted iocShells.

All OPC channels now connect.

0510 hrs. local -> 
Arrived at site an found LN2 dripping on ground at the broken weld joint on the ambient air vaporizer -> piping from CP5 to ambient air vaporizer frosted -> piping from dewar to ambient air vaporizer was warm (not frosted) -> GN2 exhausting out exhaust piping and exhaust check-valve bypass valve closed -> closing then opening instrument air to LLCV confirmed that LLCV was, in fact, stroked fully open as indicated by CDS (100% open) -> magnehelic diff pres level gauge at 36" = 87% which agreed with CDS indication of 86% full -> discrepancy between observed pump level (LN2 present in regen line and pressure difference between vapor volume and liquid volume in pump(????))

Conclusion: 
Actual pump level is "over full" -> PID response was correct for the incorrect level indication -> I don't have an explanation (yet-still waiting for the coffee to kick in) as to why the magnehelic and CDS source pressure transducer indicated levels don't indicate an over full condition ???? -> For now, I'll ignore the indicated pump level and set the LLCV at 75% open (manual) and let the actual pump level fall off -> indicated pump level may correct when over full condition is absent????

(Late Post)

The new edge switches at EX and EY were connected to the core today.  The wireless AP at EY has been moved to the VEA and attached to the new switch - also verified that the signal is still strong in the entry area, so most (all) of the building that needs wireless coverage should have it.  The wireless AP for EX will be installed tomorrow.  Once we have a couple days running experience with the new switches, we will start moving the vacuum and FMCS systems to the new switches in advance of decommissioning the old switches.

(Jumbo frames enabled, IOS 15.0.2SE2 at install.)

I modified the BSC-ISI master model to introduce the sensor correction path from the ground instrument (STS-2) to the stage 1 of the ISI. I added the 9 STS-2 inputs (3 signals per STS-2 and 3 STS-2s at the corner station). Now, 50 sensors signals feed to the BSC-ISI models.

The input filters of the STS are named: IFO:ISI-CHAMBER_ST1_GNDSTSINF_Group_DOF. In the existing stage 1 sensor correction block (the block was created to perform the sensor correction using the L4Cs of the HEPI), I added to the filters names dealing with the HEPI L4C the prefix HPI_L4C.
In this block, I also added filters (FIR and IIR) for the sensor correction path using the STS-2s. The prefix used for these filters is GND_STS. I integrated in the Master overview screen the STS and modified the stage 1 sensor correction path. A dozen of the screens were also created. While I was modifying the model, I also increased the sample rate of the excitation channels to 4K. I only installed the new model on ISI-BSC6.

I started to work on the Version 3 of the commissioning scripts to consider these changes in the models. For the moment, I have upgraded the “Routine 0” of the scripts to introduce the calibration filters of the STS-2. The STS-2 signals are added to the CPS after passing through a series of filters. I created a routine to load the IIR and FIR filters used to create the high pass filter. The companion filters ISI_4k_FIR_companion_filters_GND_STS_20130509.mat in userapps/release/isi/common/filterfiles. These filters are only usable for the ground path sensor correction (Different names for HEPI L4C)

I also created a routine to compute and load the “Match” filters used to correct the calibration errors between the STS-s2s, the T240s and the CPSs. The CPSs are used as reference. The reference is the simulated Cartesian transfer functions with the ISI damped.

In attachment, you can find the new overview screen (BSC-ISI_Overview.png). The modifications are visible are in the red box.

After measuring transfer functions from the STS-2 to the T240s (ISI damped) and using the damped transfer functions, I computed the match filters for the ground path sensor correction. The match filters are just gains close to 1 (+/- 3% correction).

I measured some spectra (calibrated in nm/s for the T240 and nm/s for the GS13 above 1Hz) with and without the sensor correction (STS-2). In the figure H1_ISI_ETMY_Sensor_Correction_20130509_155200.png, spectra are measured in the following configuration:
- High gain on L4Cs and GS13s
- On stage 1, blend at 250mHz with the T240s in the super sensor in X, Y and 750mhz without the T240s in Z, Rx, Ry, Rz.
- On stage 2, blend at 250mHz in X, Y and 750mHz on Z, Rx, Ry, Rz.
- UGF: 15Hz for all DOFs
- The plots with the "ref" label indicates that the sensor correction was engaged.

Results are pretty good especially in the Z direction (the blend frequency is 750mHz whereas it is 250mHz in the X and Y directions). Tomorrow, I will increase the UGFs of the isolation filters on the 2 stages.

We leveled the optical path from the laser to the first MCL PZT mirror, but things didn't improve much.

The first Faraday transmission is fine (first picture, EOM and the second Faraday removed from the path, picture taken in front of the second lens).

EOM transmission is ugly when the beam passes through the middle of the input and output aperture (second picture).

After fiddling around with the EOM alignment using 4 DOF stage, we always ended up with the beam very high on the input side. (no picture).

After the EOM, when the second Faraday was inserted, it makes many ghost beams /halo  in PIT (third picture). This vertical pattern doesn't change much with alignment.

Using an iris, we can get rid of most of the ghost beams (last picture). The central part of the beam is not totally round, this comes from the EOM. This looks somewhat better than OAT days (sadly).

Anyway, since it is convenient to open up the iris to see the retro reflected beam from ETMY, we left all irises wide open.

The Faraday makes many ghost beams for the refl beam too, but all of these seem to fall on the PD.

We measured the power level right at the laser, downstream of the first Faraday, downstream of the EOM and downstream of the second Faraday. Jax will post the numbers.

With approval from Keita to proceed, Kiwamu got the Mode Cleaner locked and tuned up a bit.  We then moved the ISI-in-a-can to as close as possible to WHAM4.  It now sits north of HAM4, I say the center of the load is about 5m away from the center of the chamber.  We monitored the lock state of the IMC and it remained locked through the duration.  The load was lifted and started moving toward WHAM4 at 1456PDT(2156utc) and was set down at the above location at 2201utc.

Damping loops were turned on for the ISIs of the IMC to support locking effort.

HAM2-HEPI was using BSC-HEPI coordinate transform matrices. HAM-HEPI commissioning will be starting soon. These matrices are needed to track HEPI's potential shift(s) (e.g. initial release, pumps restarted, ...).