ETMY tripped while switching blends on ST2. Attached ST2 plots

This is sheila

ITMX ST2 tripped on GS13 while switching horizontal blends on ST1. Plots of ST1 attached

Yesterday the lower Keel plate was installed.

Today the lower Keel plate was bolted down and torqued, outer gussets added. Up facing Keel has all of the 448 3/8 helicoils installed. The plate needs to be put on blocks to finish additional helicoils. 

Big events: Opening the Y-Arm gate valve to look down with the ALS beam.

- David and Greg in LVEA to fix a cracked pipe on the CO2Y

- Apollo is craning in the west bay and beer garden

- Reset ISIs, watchdogs tripped possibly by earthquake last night

- Aaron to pull cable at EY

- Joe, Justin, Gerardo to replace ALS light pipe at HAM1

- Richard, Keita, Fil, Corey working on cameras at ITMY spool

- Ken and Richard to install weather stations

- 10:19 AM PT the GV-18 opened to look down the Y-Arm

- Patrick restarts H0EPICS2

(Joseph D., John W., Justin B., Sheila D.,  and Gerardo M.)

Shutter installation finished today.

The viewport will need to be pulled sometime later for a close inspection and or possible replacement.

I moved x1boot to a different location in the rack, requiring a power down and restart.  An fsck was run on startup, delaying the boot process by over 30 minutes.

Cyrus R., Richard M., Patrick T.

h0epics2 runs the fmcs, tidal and weather IOCs.

Although the weather and fmcs IOCs appeared to be running fine (I did not check tidal), h0epics2 was nearly unresponsive to log in attempts. When I restarted it, it would not mount /ligo. Cyrus noted that it was trying to mount h2boot, which no longer exists. Fixing this allowed it to mount /ligo. Cyrus took the opportunity to apply the OS updates. Once that was done I restarted the h0fmcs, h0tidal and h0weathercs IOCs. I also started the h0weatherey IOC, which was the reason I had tried to log in to begin with.

Greg / DavidH
At ~0930 we were notified that a cut to one of the TCSY cooling hoses had been observed, and despite there being no leaks, it was decided to remove the affected length of hose near the table enclosure feed-through (cut out). No sharp edges were noticed on this feed-through, however as a preventative measure some clean room tape was applied around this cut out and then also around the two hoses before reconnecting them up. The chiller was operated and no leaks were observed.
The cooling hoses to TCSX were also inspected and no damaged was found. However, as a preventative measure, clean room tape was also applied around these hoses where they passed through the feed-through. It was decided to not disconnect these hoses (to apply tape around the enclosure feed-through) since no damage was observed and disconnection within the enclosure could introduce water leaks.
See attached photos. 

At behest of others -> GV18 will be closed later today

To avoid HEPI tripping on L4Cs, I made a simple script to raise the WD value to 99999 on HAM2 HAM3 ETMX ETMY ITMX ITMY. This task can be automated daily by running crontab on a script machine but this needs a SEI approval !
Script is called ResetL4cwd.sh and lives in /ligo/svncommon/SeiSVN/seismic/BSC-ISI/H1/Common/Misc

no restarts reported.

The pressure is dropping as 1/t^0.87. There is still water diffusing out of
materials. It should be safe to open the gate valve to the trap and the beamtube
for periods of hours. If the pressure drops below 2 x 10^-8 torr when the chamber
is exposed to the trap and the beamtube, the gate valve can be left open permanently.
The plot shows the current trend.

Wanted to check the clipping in Green path at EY. Since EY doesn't have WFS ready, the only thing I can do is to see the QPDs, which is not that interesting, but I asked EX people to do this kind of thing for EX using QPDs and WFSs to check the full green REFL path.

What was done for EY:

• Center the QPDs using QPD servo, and disable the servo (though I could have done this with the servo engaged).
• Hold the SUM output of the QPDs.
• Dither PZT1 or PZT2 in PIT (or YAW), measure the TF from QPD PIT to QPD NSUM.

If there's a clipping there's a linear coupling to NSUM, but it's difficult to get a sense of how large the excitation is. To get that sense, we look at QPD PIT signal itself. Apparently, PIT signal depends on where the QPD is placed (e.g. QPDB is mostly insensitive to PZT1 while QPDA is less sensitive to PZT2 than QPDB is, and this is by design), so we need to pick a good QPD for a given PZT. I didn't mix QPDs as using one QPD looked good enough.

Anyway, this is only with QPDs and thus things are simple, you need to look at QPDB for PZT2 (left top, blue) and QPDA for PZT1 (right top, red). 50dB difference between the beam displacement on the QPD and the NSUM signal. This might be some small clipping or inbalance in the QE or in the transimpedance or maybe some coupling via cable, but the point is, this looks good.

As I wrote above, you should be able to do this using WFS and check the full green REFL path.

In preparation for peeking down the Y arm tomorrow, I checked the video hardware to monitor ITMY (as it turned out that we don't have IY baffle diodes).

Both the spool camera and the BSC camera cans were there and the cables were still coming out of the cans. I asked Filiberto to find if the cables are still routed to the control room.

Something must have happened while I was working on the WFS path, and when I looked at the beat note before returning to the corner station the beat note was -40dbm. (Was -10dbm before).

Changing temperature had almost no effect. Measured the IR power from Prometheus and the fiber, both were good.

Started realigning the path and eventually got back to -16dbm at about 40MHz. Still big, though not as big as before.

Now the laser temperature is 35.6 degree C (was 33.7 before), though to me both of these temperature look perfectly fine.

(Filiberto, Aaron, Thomas, Daniel)

We installed the baffle PD amplifiers for ITMY. This is a new double chassis, so we replaced the old single unit. This should also fix channel 4 for the ITMX diodes. Previously, channel 4 was connected to channel 3, but now is back on channel 4. The TwinCAT system has been reconfigured to recognize the new channels.

Dave H, Alastair, Thomas, Greg

Quick summary of progress:

TCSX:
Laser was operated for a few hours on Monday with an output power of ~58.5W. Optics have been mounted and placed in position on the table. This table is now ready for alignment.

TCSY:
Optics/mounts have been staged, and are ready for table installation. Cabling is almost complete. Attempts were made on Wednesday to operate the laser/test the output power, however this was unable to be performed due to a fault with the paddlewheel flow meter (amongst other interlock/laser controller issues that are still to be tracked down). Some additional cabling is still to be installed. 

TCSX/Y periscopes have been partially assembled, still to track down one last component. Socket head cap screws with lower profile heads have been ordered, as it was observed that the cap screws for the periscope base sit proud. 

A magnitude 8 earthquake coming from Chile tripped all the BSC-ISIs on 04/01/14. Sheila's wd plots show that the ISIs tripped on the actuator watchdogs. We suspected that the servo loops were trying to compensate for the common mode seen by the BSC-ISIs at both ends of the arms, thus saturating the actuators. We studied the ground motion recorded by the ground STS at the corner station (BS-STS) and the ground T240 installed at EX (EX-T240) at the GPS time provided by Sheila, in order to find out.

On the attached document:

• p1:  The time series recorded along X,Y and Z* show the three consecutive waves of the earthquake, coming one after the other: P-wave, S-wave, and then the surface waves.
• p2:  The common motion is highly dominant along the degrees of freedom which are the most affected:
  • Z for P-wave. Amplitude peak corresponds to actuator trip time.
  • X and Y for S-wave
• p3: The ground sensors show a high level of coherence below 0.1Hz, We expect to see most of the common motion there.
• p4: Most of the motion is seen below 0.5Hz. X and Y are affected the most .
• p5-7: The differential motion is smaller than the common motion by up to a factor 6, in the frequency region of interest.

We could considerably reduce the amount of signal sent to the BSC-ISI actuators during a major earthquake (factor as big as 6), and thus reduce the risk of saturating the actuators, by removing the common mode from the signal we feed to the servo loops of the BSC-ISIs.

Data, plots and scripts are commited to the seismic SVN:
/ligo/svncommon/SeiSVN/seismic/Common/Data/2014_04_01__Chile_Earthquake_Data/

Note 1: X and Y had to be swapped on EX data, and a minus sign was also added to the new x-axis EX data. It is likely that EX T240 is mis-oriented.
Note 2: The calibration of EX-T240 was still the one that JeffK made, at the time we looked at. RichM updated it since.

Since Saturday the ODC for the PSL and (obviously) IMC have looked a little odd. They both keeping reporting very short, quick times when both the systems are not 'good'. These happen throughout the day as you can see by the two attached plots which show yesterday's activities (you can see more of these plots on the summary pages - https://ldas-jobs.ligo-wa.caltech.edu/~detchar/summary/). Just wanted to check you knew about this and if so is this nothing to worry about? Thanks!