Attached are plots of dust counts > .5 microns during October 7, 2011.

Attached are plots of dust counts > .5 microns.

H0:PEM-LVEA_DST12_5: > .5 micron counts in the new H2 diode room
H0:PEM-LVEA_DST13_5: > .5 micron counts in the new H2 laser room enclosure

Brushing of the floor was completed this morning. On a positive note, only two drills were required to clean the chamber! First vacuum was finished and wipe down is about 80% done. Some black "crusty" stuff was found on portions of the downstream beamtube nozzle. It required scraping with a razor blade to release from the surface which appeared "pitted" in the areas where "crusties" were found. After I inspected a sample and observed the scraping in action, I consulted with Michael L. We agreed that all areas that had "crusties" should have a post-work FTIR taken. 

For the last month or so, the SEI assembly crew has been trying to figure out the source of a lateral "twist" in our third BSC assembly. When we initially loaded and released the ISI (~ 1 month ago) initially we found an approximately .060" rotation in Stage 1 relative to our nominal position. After replacing the flexures and springs,as well as measuring the Stage 0-1 spring posts for machining errors, we adjusted the springs on their mounts (using available dowel pin slop to rotate the springs to counter the ISI's rotation), we floated the ISI a second time and found a .040" rotation. This is close to what we found on the second assembly (BSC6), but this rotation was enough that we could not connect horizontal actuators. For our 3rd round of releasing the springs, we replaced the flexure brackets and gussets. Measurements of old and new brackets/gussets showed no differences, no off angles on either set. This time when installing flexures, though, we pushed sideways (in the plane of the ISI rotation) on the bottom of the flexure, hoping to offset more of the rotation. It seems to have worked, as we now find ~.007" rotation. 

All the actuators have been installed and they are all connected to the Four-way Valves.  As usual:
*** Don't operate the Valves  *** at the tops of the piers.

This is the first HAM completed at LHO.  A few photos attached to show the routing.  These have not been pressure tested--they can't until the compete main lines are put in place.  Routing has been checked by Worden and McCarthy in regards to Vacuum & Electrical interaction.
The first image is the North end of HAM9--this is the busy end as far as plumbing.  The second photo is  half of the South end and is about as busy as it gets there.

Last week, the ITMy compensator plate (CP09) was transported to the LVEA and installed into the QUAD reaction chain lower structure.  It was suspended from it's loop and found to hang decently.  Apon hanging the CP, RePUM, and ReUIM as a triple unit, we found the CP was hanging at 1.6mRad, so we proceeded to lock it down in prep to reattach it to the main chain.  Pictures are on ResourceSpace:

https://ligoimages.mit.edu/?c=761

Note that in the pictures, the Reaction Chain with the CP (left) is sitting in front of the Main Chain (right) in order to gain access to the IAS equipment to the right of the cleanroom.

Lots of progress made this week with assistance seven colleagues from AEI and LZH in Hannover, Germany (Maik Frede, Mathias Janssen, Raphael Kluzik, Michaela Pickenpack, Oliver Puncken, Benno Willke, Lutz Winkelmann) and Peter King from CIT as well as Michael Rodruck, Dave Barker, Cyrus Reed, Richard McCarthy, Patrick Thomas, Irena Libby, et al. from LHO.

The PSL components were uncrated and moved to the LVEA, then into the Laser Diode Room, Chiller Room, and Laser Area Enclosure.  The high-power oscillator (770 lbs.) was moved into position on the PSL/IO table along with the front end laser, diagnostics breadboard, and pre-modecleaner assembly.  The fibers for the 800 nm pump light were run between the Laser Diode Room and the Laser Room.  Hoses were installed between the chiller and the water piping and the system was charged with water and tested.  The scheme for removing the chiller heat by dumping it into the LVEA return air plenum via an exhaust chimney appears to be working well.  Video cameras are operating and generating Laser Room and Ante-room images that are being displayed in the control room and outside the Laser Room in the LVEA.  Cabling work in the Laser Diode Room and PSL racks adjacent to the Laser Room is ongoing.

On Monday, we plan to begin commissioning of the front-end laser (35-W laser like that used for eLIGO).

After discovering there was an unacceptable amount of twist happening between Stages 0-1 on BSC Unit #3 the springs and flexures were uninstalled and replaced with new ones.  New flexure brackets were installed as well. The new parts are as follows:

	Corner 1
	Spring 0-1 s/n 15
	Flexure 0-1 s/n 138
	Flexure 1-2 s/n 140

	Corner 2
	Spring 0-1 s/n 10
	Flexure 0-1 s/n 131
	Flexure 0-2 s/n 132

	Corner 3
	Spring 0-1 s/n 13
	Flexure 0-1 s/n 150
	Flexure 1-2 s/n 120 

 The twist is now down to less ~.007" but we'll need to re-level to be sure. Regardless, this is much improved over the previous state of affairs.

(Corey, Filiberto, Hugh, Jim, Mitch, Vincent) 

****  This covers Testing & Installation of Cables for BSC8 which covered much of this week.  ****

Swapping Cables & Laying Them Out For Final Configuration

Other than the Capacitive Position Sensors, cabling for the BSC8-ISI had been Class-B.  This week we swapped out these cables for Class-A cables, and  positioned them on the ISI in a "final configuration".  Photographed cable layouts, and posted in ResourceSpace, here.  Below are the serial numbers and locations for all of the cables we installed this week.

Cable Serial Numbers

SUS Viton Cable Clamps Installed

Swapped out Peek cable clamps with newer Viton Cabl Clamps for the SUS cabling strung on the side (at Corner3) of the ISI (we did NOT address any clamps on the Optical Table. (photo of Jim installing a clamp is attached)

Testing Seismometer Cables

Before connecting cables to the Interface Feedthrus and Powering ON the seismometers, we used our Emulator box to test out the cables for the L4C's and GS13's.  (We were not able to test out the Trillium Cables; we tried the STS2 Emulator, but this did not work for us.)

Balancing Stage 2 & Capacitive Position Sensor (CPS) Issues

On Wed night we made an attempt at checking/balancing the ISI because the SUS group wanted to run measurements on a floating ISI.  We were surprised at how much Stage2 was off.  It took a while, but we were able to get all the Vert CPS under 0.5V. 

After this, we locked up Stage2, and unlocked Stage1 to begin balancing, but then we noticed we had a railed (+13V) V3 CPS.  In all liklihood, we are going to have to swap this CPS and board out (we checked it and its cabling several times to no avail).  

I called in Dave Barker to diagnose an issue with the test stand. I wanted to create a DTT job to look at X1:SUS-QUAD_M0_OSEMINF_F1_OUT and 19 other X1:*_OSEMINF_*_OUT channels (with a view to getting the dewhitened noise signal from a batch of AOSEMs which will presently be hooked up and tested for noise). 

The problem that I saw was that only of order 5-6 channels had valid data - the rest had garbage (typically a few non-zero data points and the rest zero) repeating on a 1 second loop.

Jeff K and I tried his new x1susquad model (with the swapped channels to allow for the new OSEM wiring) and saw the same problem. We reverted to the old model and still saw the problem so we put the new model back in place.

After a few reboots of the test stand and much head scratching, we found the problem was a marginal .ini file (  /opt/rtcds/tst/x1/chans/daq/X1SUSQUAD.ini ) which was logging so many channels that there was no processor time left over to look at 20 test points. Dave Barker saved the large version as X1SUSQUAD_verylarge.ini , and put in a minimal one (there's a rule that at least two channels must be uncommented). I made a spare copy of the minimal one at X1SUSQUADminimal.ini . We will need to swap back in the large one before trying to do transfer functions.

A fiber pulled at LHO was shipped to Glasgow in the aluminum tube shipping container design by Doug. On arrival fiber was in one piece and was tested for strength by hanging 15 kg from it for 24 hours. Fiber passed the test, which is good news.

Support table, viewports, and feedthroughs were removed. Condition of chamber was documented. Pre-work wipes and FTIR samples were taken. Compressor trailer was moved into the LEA/High Bay. 

I'm sharing this list as a guide to which alarms I clear on activation, as opposed to those I respond to according to the guidance provided. Operators who are more or less familiar than I am with the status quo of operations on site should communicate with each other and system leads for updated procedures

• 4K_TCS:
  • H1:TCS-ITMX_LSR_HDTEMPDEG: This alarm corresponds to the temperature of the TCS laser head for H1's ITMX. Although the temperature of the laser head was stable (typically +/- 0.01 DegC), it was in a HIGH alarmed state, so Cheryl instructed me to shut down the laser. By Monday, this issue should be resolved.
  • H1:TCS-ITMY_LSR_HDTEMPDEG: This alarm is the same as above. The laser was off but the temperature was below the allowed range, so the range may need to be adjusted.
• FMCS:
  • H0:FMC-CS_LVEA_ZONE4_E_DEGF: This alarm corresponds with the temperature sensor labeled 4-E, in the Northwest part of the East Bay. The thermometer is giving a flat 0 DegF, which converts to a flat -17.7 DegC. RichardM is aware of this problem.
• Temps
  • H0:PEM-LVEA_DST8_TEMP: This alarm corresponds to the temperature readout from Dust Monitor 8 in the South Bay of the LVEA (according to the H0PEM_DUST MEDM). It alarms because there is no signal. Patrick is aware of this.
• H0DUST
  • Assorted alarms with white alarm states: The white alarms indicate no signal to various dust monitors. Patrick is aware of these.
• Vacuum
  • Ion Pump alarms in LVEA northwest of GV3 and GV4, corresponding to vented H2 volumes.
• 4k-PSL
  • H1:PSL-FSS_RCTEMP: This alarm corresponds with the temperature of the Reference Cavity of the H1 PSL, which is also very sensitive to temperature fluctuations. If the temperature, as compared to earlier days, looks cyclical and virtually the same as the previous period, I contact MichaelR to update the alarm values to reflect seasonal changes.

All other alarms are responded to according to the guidance provided by the EPICS Alarm Handler. Stay tuned for door alarms in a different post.

Attached are plots of dust counts > .5 microns.

- H2 PSL work continues with help from Peter King and the visiting group from Germany

- EY: Painting of the VEA floor

- EY: Cyrus heads down to EY to pull a cable

- Patrick installs a dust monitor at the H2 PSL

- ICC in HAM10

- H1 TCS Lasers turned off due to temperature anomalies. Tidal file regenerated. Good duty cycle today, as H1 locked up to OMC locking on its own.

Similar to what I've done for the X1SUSQUAD's model yesterday, H2SUSITMY's model had to have some channels re-arranged given the new M0 / R0 OSEM arrangement shown in T1100327-v3 and D1001725-v7. This update is now complete for H2SUSITMY (only). 

In addition, I've brought the QUAD_MASTER.mdl library part up to the standard we'd finished with the triples at LLO a few weeks ago, in that the M0, L1 and L2 stages now use the SIXOSEM_F_STAGE_MASTER.adl, FOUROSEM_STAGE_MASTER.adl and FOUROSEM_STAGE_MASTER (respectively), and all stages use the sus-subsystem-wide-usable WATCHDOG.c instead of the quad-specific QUAD.c. Because their control schemes are unique to the QUAD, R0 and L3 do not have their own stage master, but are left as part of the overall QUAD_MASTER.mdl library part. Finally, the BIO interaction has been brought up to the "RCG2p3 Strategy" referenced in T1100507.

J. O'Dell, J. Garcia

Continuing with the diagonalization of the FMY M1 OSEMs, mechanical adjustments to the FMY top mass (M1) were made to further decouple the "F1" and "SD" OSEMs from the Yaw DoF.  The same sine wave excitation at 1.4Hz was injected to the "H2:SUS-FMY_M1_TEST_Y_EXC" channel with a 100ct amplitude. The expected contributions to the "Yaw" transfer function should be the "F2" and "F3" OSEMs with desired isolation of the other OSEMs ("F1", "RT","LF", "SD") at ~30dB or less.

Initial measurements indicated the "F1" OSEM to be ~10dB isolated from Yaw, with the other OSEMs at ~30dB isolation. Our reasoning was the "F2" and "F3" OSEMs were not in line with the center-of-mass of M1, causing a slight Pitch that would manifest itself in the "F1" OSEM response.  To lower the COM of M1, a 300g mass was added to the top of M1.  The OSEMs were then realigned to center the flags and the first pdf is the same measurement with this configuration.  The "F1" response is roughly ~20dB lower than "F2" and "F3" and the "SD" response about ~17dB lower.

"fmy_osem_diag_yaw_add_mass_300g_f1align_111005.pdf"

This promising result encouraged us to add more mass to lower the COM further.  A 100g mass was then added to M1. At this time, it was noticed the flag of the M2 LL OSEM was twisted and possibly rubbing against the OSEM photodiode sensor and/or LED source.  The M2 LL OSEM housing was removed, and the subsequent measurement is displayed on the second pdf.  The "F1" isolation is now at ~25dB and the "SD" OSEM now at ~29dB.  

pdf #2 - "fmy_osem_diag_yaw_add_topmass_400g_f1alignm2llosemoff_111005.pdf"

The flag for the M2 LR OSEM was noticed to be twisted as well, and it's OSEM housing was removed.  The current configuration of the FMY is the M2 LL and LR OSEM housings are removed, there is now 400g added mass to the M1, and the M1 LF and RT flags are out of range of their respective OSEM beam paths due to the added mass.

Since we've moved forward with the suggested clean up of the TOP stage of a QUAD's cable routing (see T1100327-v3, D080273-v2), this change needed to be accounted for in the test stand's simulink model, given that the order of the analog inputs have changed as a part of the clean up. I've edited, compiled, and installed the simulink model
/opt/rtcds/tst/x1/cds_user_apps/trunk/sus/x1/models/x1susquad.mdl,
to reflect the new input order as defined on D080273-v2:

ADC Channel     Signal
0               M0 F1
1               M0 F2
2               M0 F3
3               M0 SD

4               M0 LF
5               M0 RT
6               R0 LF
7               R0 RT

8               R0 F1
9               R0 F2
10              R0 F3
11              R0 SD