(Alexa, Daniel, Sheila)

We measured the WFS sensing matrix for both PIT and YAW. The matrices were computed by exciting ITMX/ETMX PIT/YAW at 1.5Hz with 0.3 amplitude, and looking at the WFS transfer function. The results can be found in the following DTTs saved in /ligo/home/sheila.dwyer/ALS/HIFOX/WFS/:

• WFS_sensing_matrix_ETMX_PIT_march28_2.xml
• WFS_sensing_matrix_ETMX_YAW_March28.xml
• WFS_sensing_matrix_ITMX_PIT_March28_2.xml
• WFS_sensing_matrix_ITMX_YAW_March282014.xml

Inverting the results gives...

YAW input sensing matrix:

-2.294    -3.155

0.529     -2.604

PIT input sensing matrix:

-0.494    -0.239

0.302    -0.489

These values are in microradians; however the factor of 1e-3 is taken care of in the gain of the filter module. We also adjusted the signs as follows:

• H1:ALS_X_WFS_DOF1_Y_GAIN = -0.001
• H1:ALS_X_WFS_DOF2_Y_GAIN = -0.001
• H1:ALS_X_WFS_DOF1_P_GAIN = -0.001
• H1:ALS_X_WFS_DOF2_P_GAIN = 0.001

Under this configuration, with all four DOFs engaged (DOF 1,2 P,Y) the WFS_A/B_I_YAW/PIT_OUTMON all converge to zero. The lock appears to be stable with a transmission betweeen 950 to 1050 counts. Futher investigation needs to be done...

Aidan. Dave H. Greg G. Thomas V.

We have, basically, finished installing all the electronics and cabling on the TCSX table. There are a few outstanding issues (summarized in the attached PDF). The ones that are preventing us from turning on the laser are listed below.

1. For some reason, the flow meter is not outputting a sense current (current proportional to the measured flow). This means that the CO2 controller, D1200745, is registering low flow and preventing the laser from being turned on. We're not sure if this is a faulty connection at the terminal block in the meter or if there is a deeper problem. We will continue investigating on Monday. The connections are shown in photo 1.
2. The TCS Beckhoff unit is, apparently, running but is not connecting to EPICS. We need to be able to access the software on/off switch to turn the laser on.
3. We don't currently have the viewport IR sensor that plugs into the CO2 laser controller, D1200745. We can bypass this input by changing a jumper on the board.

We hope to address all these early on Monday to get the laser running to check the output power.

Chiller settings:

We adjusted the bypass valve on the back of the TCSX chiller to achieve the following settings (to mimic what's at LLO)

Flow rate: 3.4GPM

Pressure: 60.5PSI

Laser housing leak.

The replacement laser installed on the TCSX table also has a slow leak from the laser housing (in the same place as the first one) - about 1 drip every 5 minutes. We will check the output power of this laser before we pull it. See photos 3 & 4

This trip happened around the time of a beckhoff restart.  A beckhoff restart causes a crash of the IMC guardian, which causes it to stop.  Its not clear to me why this should cause MC2 to get a large signal, but it seems to.  This causes a cascade of trips.  Even though I don't know why this happends, creating a safe state in the IMC guardian so that it handels missing channels better could help with the problem. 

Another solution is to have the SUS WDs not trip HEPI.  Can we get that fix soon?

HAM2 also tripped at the same time, Jeff and Hugh brought that back. 

Please mind the signs here at HAM4, there is an Optic suspended here.  Commissioning to commence shortly.

Day Shift Summary
LVEA Laser Safe

Apollo - Bolting dome on BSC10, working on view ports at End-Y
Mitch – Check ACB at End-Y
Hugh – Working on HAM5 HEPI
Richard – Y-Arm TCS cabling

08:35 Mitch – Going to End-Y
08:53 Dave – LVEA working on TCS cabling
09:00 Justin – Moving laser barriers around the HAM4 TCS table area
09:18 Andres – Working on dog clamp shelves next to HAM2
09:20 Hugh & Jim – Working on HAM5 HEPI 
09:29 Betsy & Margo – Going to End-Y for BSC10 closeout
11:26 Filiberto – Going to Mid-Y to pick up TCS panels
13:00 Justin – Transition LVEA to laser hazard
13:20 Dave & Thomas – Turning on TCS chillers
14:00 Filiberto – Going to End-Y to check ACB feed through
14:05 Andres – Working on dog clamps shelves next to HAM2
15:30 Jax – Briefly transitioning End-Y to laser hazard to make a PZT check
15:36 Michael – Going to End-Y to check chamber close status 

At Richard's request I disabled the End Y picomotors, so that they will not be used durring the pumpdown.

Tested the forward voltage for the ACB diodes. 
BSC10 Flange F1-3C1 (air side).

Pin 1&2
PD forward voltage: 0.431V


Pin 4&5
PD forward voltage: 0.423V


Pin 7&8
PD forward voltage: 0.431V


Pin 10&11
PD forward voltage: 0.423V

All results within spec.

Margot and I performed all of BSC10 closeout tasks listed in my previous alog regarding this closeout.  We pulled the FC from the ETMy optic a little after 11am, and the door was going on at ~1:30.  It took "so long" (ha) because we ended up having to spend some extra time calling in the troops about one of the ISC viewports having what appeared to be a scratch on it's inside surface.  More details to come as needed.

Jim locked the HAM5 ISI and then we floated the platform on HEPI.  A couple of Spring adjustments and we are level on the Optical Table to +-0.1mm.  Not sure about the elevation yet but it is likely close to Spec.  This will be good enough for continuing the ISI commissioning which we may get started before days end.

Please mind the signs--There are no optics here but HEPI is unlocked & floating; also please mind the Dial Indicators--Thanks--H

ITMY HEPI tripped. Reset.  

I've created a new folder on the desktop for WD trip plots, if operators could help us to plot and post these each time there is a trip it would be greatly appreciated.

You can create the plot by opening the WD screen, before untripping idenify the type of trip by looking for a red box in the First Trig column.  Use the blue buttons labaled Plot ACT trip to make the plots (it will pop up after a while).  Use the magnifying glass in the plot window to zoom the plot to the relevant time scale, then take a screen shot.  You can store this in the WDTrip folder on the desktop, and then post it in the alog. 

Jamie, Fabrice,

I am posting for the records and for discussion the WD trips we observe while tuning the turn on procedure for the guardian.

no restarts reported.

Here is an update on the instruction for untripping seismic, with some new tips from Fabrice, especially for ETMX. 

Untrip HEPI WD, use Commands2 window to isolate level 1 on all chambers except BS which is level2

Untrip ISI WD (you may need to raise T240 Threshold)

reset CPS offsets,

• go into stage 1 bias screen hit reset CPS offsets, then hit store targets.  
• Repeat in stage 2 bias screen. 

Check that everything is in high gain: (this is also good to check if you are already isolated but have a lot of motion)

• Click on the three T240 screens, check that the filter modules labeled gain are ON
• In the L4C screen check that the filter modules labeled gain are OFF
• in the GS13 screen check that the filter modules labeled gain are OFF

If you have been struggling with switching the blend filters, you may want to zero the T240s.  You can do this in the three T240 screens by tuning on the AutoZ filter module in the X filter module, then turning it off.  

Use commands, isolate level 3 for most chambers. For ETMX start with Commands, Isolate Stage 1 Level 2.  Once this script is finished, isolate stage 2 level 3.  

Switch Blends:

• Go to stage 2 bleds switch all to Tcrappy.   If this failed you can 1st switch Z from Start to Tcrappy, once it has switched RY, RZ, RX, Y, and X.
• Wait a long time......until the T240s are have hundreds of counts. 
• Repeat for stage 2.
• There is a switch all button, that might save you from having to do one at a time, but can often trip the ISIs.   

good luck...

Aidan, Dave H, Thomas

More cabling and plumbing.  The leaky laser from ALOG 11019 was replaced with a new one and a matching RF driver. We're in a position to be able to turn on the laser mid-morning tomorrow.

The new ITMx monolithic welding has been successfully completed and was left suspended overnight last night.  The majority of the modal measurements have also been completed today, with the exception of the violin modes, which are proving to be trickier to measure than in previous suspensions.  We will continue with these measurements tomorrow with some different equipment.  Stay tuned for subsequent posts with IAS and modal measurement numbers.