HughR, MitchR, JimW

Today Team SEI pushed through most of the worst of the seismic optical table payload, but we ran into a couple of known issues. LLO found that these mass stacks somewhat interfere with the BS struts. But where Livingston only had to shift a few 1kg parts around, it looks like we have to move a 5kg mass. In the attached, somewhat cryptic, picture, the mass stack directly under the strut, and closest to the camera, is missing the interfering 5kg mass. We plan on shifting this mass to a neighboring stack, but that does mean the stacks will not be as uniform as on previous units.

For Robert and Keita I have reconfigured H2 DAQ to serve EY data which is archived on the frame writers disks. The ini files were set to acquire=0 before being put back into the h2dc0 master file.

The following systems were restored to the DAQ:

H2SUSETMY, H2SUSTMSY, H2HPIETMY, H2ISIETMY, H2ISCEY

The H2DAQ frame is now 9.2MB per 32 second frame, this is all slow data.

Unfortunately, the course alignment of the ITMy (BSC1 cartridge test stand) was not done last week.  Today, we started the fine alignment and discovered the main chain was mechanically grounding on one of the F3 magnet replacement blocks.  This required that we adjust the entire table cloth to alleviate this, (and then all 12 BOSEMs to follow that - ugh)!  The chain then swung further forward causing a larger yaw error.  So, we're back to yaw and pitch alignment.  Fortunately, Doug just had a crash course on yaw alignment techniques and is slowly working at it (an iterative process).

This morning, Filiberto swapped the SUS/HAUX cables on the outside of the chamber to the correct feedthru port.  However, there are now funny looking signals on MC1 Middle (M2-UL) and MC1 Lower (M3-LL).  Reportedly, there was an external cable switch and the signal stayed with the channel exhonorating the external cable as the problem.  To be continued...

[LukeW and RickS]

For the main input beam, we have assumed the center conflat flange is centered laterally in the HAM 1 door.

Yesterday, while checking the beam path between the IO periscope on the PSL/IO table, we found that the 10" conflat flange on the HAM 1 door is shifted to the left (when viewed from outside the chamber) by about a half an inch.

This impacts the performance of the shutter and beam dump that mounts to the input window housing - too much lateral offset and the beams might miss the silicon carbide dump.

We hoped that we might find another HAM door on which the conflat flange centering would be better.

Here is what we found for the positions of the center conflat flange relative to the HAM door (and HAM chamber flange) centerline (tolerances +,- 1/16"):

HAM1 9/16" to the left
HAM6 9/16" to the left
HAM7 5/16" to the left
HAM12 9/32" to the left

Replacing the HAM1 door with either the HAM7 or HAM12 door would get us 1/4" or so, but not likely enough to be worth the effort.

We will look for other options to better direct the beam through the various apertures.

At approximately 23:00 PST Nov. 8, both network trunk connections between the MSR and the h1 electronics room switch failed.  This caused loss of network access to the PSL enclosure for cameras, alarms, and control workstations.  

The cause of this failure is unknown.  The h1 electronics room switch was power cycled to restore the connection, so the likely failure point was that switch.  

The dust monitor labeled 'R' was put in the OSB bake oven room. It was started in the software around 9:34 AM.

Jeff B & Andres R

  We installed the Upper Structure Stays on the BeamSplitter mounted on BSC2. 

With Giacomo and Paul, we installed the MC3 suspension into HAM2 this morning.  The arm was able to reach the desired placement on the table easily, despite reports of skepticism.  After lunch we removed the cookie cutters and finished placing all of the dog clamps on MC3 and MC1.  There is one outstanding dog clamp due to a missing helicoil in it's spacer (to do tomorrow).  We then plugged in 6 of the 7 OSEM cables for MC3/MC1, placed the table cable brackets as per the layout dwgs, and stowed the loose cable coils.  Note, the SRS cables were a bit tight in the PEEK connectors down on stage 0 (?) of the ISI and I could not pull through any slack so I had to loosen all of them for MC3 in order fo the tablce cable bracket to make it to the appropriate spot on the table***.  Filiberto came out and connected all of the external cables from the feedthru to the satellite boxes, however after he left we noticed that the internal cable connections from the SRS cables are on the flange 180 deg out on the chamber.  Doh!  So, either the external lacing is on the wrong feedthu port, or the internal SRSes are - I have not checked.  Hopefully a quick fix tomorrow such that I can suspend and damp. 

***SEI - please see that I have not made any of the jumping segments too tight and shorted the stack.

I'm also planning to remove the FC tomorrow such that flashing of the MC can commence asap (and while I'm at LLo next week).

Mark B.

Starting TFs on both chains of ITMy. Will get as far as possible this afternoon and then hopefully continue later tonight. Priority is undamped M0 and R0, then damped M0 and R0.

The cleanroom was moved back over the chamber and a C-3 soft roof installed. We try for two cleanings and dome removal tomorrow.

The cleaning crew got two cleanings in early this morning and the Apollo crew staged for door removal. The Apollo crew started working on door removal about 1:30 pm. By 2:30 pm, both the east and west doors had been removed from the chamber.

Summary: We have removed eddy current damper magnets from M0 of the quad in hopes of reducing magnetic coupling. However, investigations show that there is also excess coupling at levels L1 and L2. I suggest removing the blade ECD magnets from L1 and cutting slits to reduce eddy currents in certain L2 parts around the AOSEMs.

We have now removed the eddy current damping magnets from stage M0 of the quad suspensions (Figure 1). This should reduce magnetic coupling, but my investigations at ETMY suggest that M0 is not the only level that has large magnetic coupling. Figure 2 demonstrates that there is also coupling at L1: there are two peaks evident on the BOSEM signals from M0 (top plot), the one on the left is produced by a BOSEM injection, only at M0. The one on the right is produced by a magnetic field generator outside of the ETMY vacuum chamber. The bottom plot shows that the relative amplitude of the two peaks is very different on the level just below, L1: the BOSEM injection peak on the left is relatively more attenuated. If the external magnetic field coupled only at M0, then the two peaks would keep their relative sizes because both would be equally attenuated between M0 and L1 (actually, the slightly higher frequency magnetic peak would be slightly more attenuated). Instead, the magnetic peak is much bigger than would be expected if it coupled mainly to the eddy current dampers on M0. A similar experiment shows that we also have excess coupling at L2, the PUM.

Since it is clear that we will have excess magnetic coupling even after removing the M0 ECDs, I had a look at the suspension to pick out what I thought would be the worst coupling sites. Here are my two favorite sites for easy improvement, that might be possible to accomplish before reinserting ITMY.

L1:  The blade spring eddy current dampers (Figure 3). I have checked with Mark Barton to see if there are any problems removing these eddy current dampers before we reinstall ITMY.

L2: The AOSEM mount base plate should probably have a slit in it so that eddy currents can not make a loop around the AOSEM so near the actuation permanent magnet (Figure 4 and drawings: ETM PUM can, AOSEM base plate. Two secondary candidates for slits would be the AOSEM translation plate and the control ring (Figure 4 and drawings  AOSEM translation plate, control ring). The control ring would simply need a non-conducting screw to tighten it.

Attached are plots of dust counts > .3 microns and > .5 microns in particles per cubic foot for Wednesday November 7, 2012. The data was taken from approximately 6 AM to 6 PM. Also included are plots of the modes to show when the dust monitors were running, and plots of the status to show when the sensor failed for the dust monitor in the bake oven room (H0:PEM-LAB_DUST_LOC_3_STATUS). The sensor failure was reported when the status changed to 1.

The Foton filter files for HAM2-ISI and HAM3-ISI were moved

from:
opt/trtds/lho/h1/chans
to:
opt/rtcds/userapps/release/isi/h1/filterfiles/

Softlink to these filter files were created in:
opt/trtds/lho/h1/chans

Dave made changes to the RCG so the softlinks mentionned above can be preserved during the make process.

Mark B.

Set MC3 to undamped at 08:55 for a 20 minute spectrum series. (We already have a nice damped interval from last night).

PAC meeting
Rick, Cheryl, installation of light pump, alignment of optics between laser enclosure and HAM1.
Sensor failure for dust monitor in Bake Oven Room.
Hugo reported DAC channels not writing correctly for h1seih23, frontend rebooted.
HAM2 viewport installation
Filiberto dressing cables in cable trays around HAM3
Operator station alarm handler moved to H1

Two visible earthquakes on seismic plots:
5.1	54km SW of Champerico, Guatemala	2012-11-07 22:42:48 UTC	13.907°N	92.225°W	35.1 km
7.4	24km S of Champerico, Guatemala	        2012-11-07 16:35:50 UTC	14.083°N	91.916°W	41.6 km

Disconnected SUS SEI field cabling from HAM3 feedthrus to dress cabling inside cable trays around HAM3. All electronics were powered off before cables were disconnected. When reconnecting cables, had Corner 1 and 2 for ISI driver (Coarse and Fine) connected backwards. Hugo is trying to bring HAM3 ISI back up.