Weekly Report for Week Ending December 20, 2007

LSC	Administration	Hanford Observatory	Livingston Observatory
Optical & Mechanical	Controls and Data Systems	40 Meter Facility	TNI
LASTI	CIT Science Group	Laboratory Computing	Adv. LIGO Development

Past Weekly Reports

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LSC Issues (Reitze)

No report this week.

LIGO Laboratory Administration (Lindquist)

STATUS OF LSC MOUs (Lloyd)

MOU status remains as reported last reporting period (see below).

• The table below shows the MOUs and their attachments that have been approved and signed off to date by both the LSC Spokesperson and the LIGO Laboratory Director.

  MOU	Attachment
  Andrews University	DAT, OPS, Z
  Carleton College	DAT, OPS, OUT, Z
  Embry-Riddle University	DAT, OPT, SUS, Z
  Eotvos University	DAT, OPS, OUT, Z
  Florida, University of	ACF, DAT, LAS, OPS, OPT, OUT, SUS, Z
  Goddard	DAT, OPS, Z
  Hobart and William Smith Colleges	DAT, OPS, Z
  Institute of Applied Physics	OPT, OUT, Z
  IUCAA	DAT, Z
  Louisiana Tech University	DAT, OPS, OUT, Z
  Loyola University	DAT, OPS, Z
  Maryland, University of	ACF, DAT, OPS, Z
  Montana State University	DAT, Z
  Oregon, University of	DAT, OPS, OUT, Z
  Rochester, University of	DAT, Z
  Southeastern Louisiana University	ACF, DAT, OPS, Z
  Stanford University	ACF, DAT, LAS, OPS, OPT, OUT, SUS, Z
  Texas-Austin, University of	DAT, OPS, Z
  Texas-Brownsville, University of	DAT, OPS, OUT, Z

  • ACIGA is still under review.
  • Northwestern, Sannio and Washington State are pending, requiring changes requested by the review panel.

PROPERTY MANAGEMENT (Luna)

>From: Rod Luna <rluna@ligo.caltech.edu>

• Writing exports and imports procedures.
• Assisted Ken Mason at MIT in making shipping arrangements for three crates for AstroPak in Downey, CA to LLO.
• Assisted J. Heefner with packing, shipping, and preparing a commercial invoice for five Switches and five Connectors to the Birmingham University in the UK.
• Assisted D. Sigg at LHO with packing, shipping, and preparing a commercial invoice for two prototype boards to the Debrecen University in Hungary.
• Assisted S. Anderson in shipping a Sun Server to Syracuse University, NY.

DOCUMENT CONTROL CENTER (Turner, Mak)

>From: Cleveland Mak <mak_c@ligo.caltech.edu>

• Processing of talks from the recent LSC/Virgo Collaborations Meeting for the most part is complete. I'm waiting to hear from the meeting organizers to determine how close we are to 100% completion.
• Processed talks from last week's GWDAW Meeting at MIT.  The majority of the talks have been processed but talks continue to trickle in.

FINANCIAL SYSTEMS (Funaro, Brambila, Oracion)

>From: "Funaro, Catherine" <Catherine.Funaro@caltech.edu>

• For ACCOUNTS PAYABLE HISTORY Press Here.

>From: Karl Oracion <koracion@ligo.caltech.edu>

• Submitted cost transfer to project accounting to closeout old Low Noise account.
• Requested travel expenditure type reclassification and labor distribution adjustments.
• Sent out reports for discretionary accounts, Low Noise, MIT.GRID and U.Wisconsin awards.
• Submitted budget allocations to OSR for first half of FY2008.
• Met with task force to discuss enhancements/improvements to the monthly OPS report.
• Attended Prism Software presentation.
• Continued to meet with project accounting/IMSS personnel to discuss possible enhancements to operations report (on-going).
• Financial reports can be found at: http://docuserv.ligo.caltech.edu/~fireport. (For passwords contact Karl)

SUBCONTRACTS MANAGEMENT (Jasnow, Salone)

>From: Gina Salone <gsalone@ligo.caltech.edu>

• Efforts are underway to more clearly separate the multiple contracts with LSU by the different campuses that are appropriate for each contract.
• We are still working to adjust the new invoice system to better accommodate LIGO's needs.  Two possibilities now being explored are the addition of the LIGO mail code, 18-34, on all invoices, so they come directly to LIGO; and, having Accounts Payable send all LIGO invoices directly here before being scanned.

>From: Ed Jasnow <jasnow@ligo.caltech.edu>

• The contract with third contractor for the Pathfinder optical polishing effort for Advanced LIGO, is being assembled and prepared for submission to the NSF for review and approval.

PROPOSALS and REPORTS (Lindquist)

The monthly report for the end of November was sent to the NSF last Friday.  I will put out a notice regarding the end of December report soon now.

CHANGE CONTROL/CONTINGENCY MANAGEMENT (Lindquist)

• There are no open change requests.

HUMAN RESOURCES (Akutagawa)

>From: Cindy Akutagawa <cindy@ligo.caltech.edu>

• The next Staffing Committee meeting is scheduled for Monday, January 14.

Quality/Safety (Tyler)

IMPORTANT SAFETY NOTICE: Personnel at the LIGO 40M lab have identified a safety hazard involving the 1064nm laser safety glasses purchased from LaserVision. The dielectric laser safety coating applied to the lens surface appears to be degrading/damaged and no longer provides adequate eye protection.

The particular type of LaserVision glasses should be removed from use immediately (do not throw-away, retain in "secured" storage pending further discussions with the vendor regarding replacement or ?).

For additional information, please contact either Steve Vass or Bill Tyler.

It is also recommended that LIGO should plan to test laser safety glasses at least once a year to verify that adequate/safe eye protection is maintained.

The LIGO All-Hands safety meeting has been postponed to mid or late January 2008.  The postponement was considered necessary due to the limited time availability of personnel involved with completing Enhanced LIGO tasks before the extended Caltech holiday period.

LIGO Hanford Observatory (LHO) and Interferometer Operations (Raab)

Summary of Activities at LIGO Hanford Observatory (compiled by K. Kawabe)

Enhanced LIGO commissioning

• This week the bias currents of H1 and H2 ITMX were relieved by adjusting PAMs and rotating the cage. The Y-arm baffle was removed.
• The UFL team reports very good isolation ratio and high transmission of their newly assembled Faraday isolator. They're going to be back in the new year for the installation.
• Dust measurements inside the vacuum enclosure.
• Visual inspection of the ITM and FM surfaces.

Post-S5 measurements and other activities

• PEM injection study of high frequency AS_Q channel.
• A snake caused the Mid X station power outage on Sunday.

Outreach (D. Ingram)

• Evan Goetz spent a few minutes answering Granger Middle School questions about black holes on Dec/4/2007.
• Intern Antonio Trevino shared some comments about engineering with Stevens Middle School on Dec/12/2007 (he attended Stevens as a youngster).
• Mike Landry, Rick Savage and Josh Myers have spoken to recent visiting groups as well.

LIGO Livingston Observatory (LLO) and Interferometer Operations (Giaime)

IO Work

• IO work largely done, all tables inspected and photographically documented (see Wednesday LLO ilog).  Once a good vacuum is obtained, we will be able to recheck alignment of the non-OMC beams.

VE Work

• Installed a blank cover in place of the window assembly on the septum so that the assembly could be reworked.  All doors are back on, and we are pumping the main volume to keep it clean and out-gassed for the holidays.  Pressure was a few mbar on Friday morning.

SEI Work

• Preparations underway for January 2nd start of SEI test stand installation.  Bolts are now being epoxied in the floor so that the slight stink can dissipate before critical hardware is brought in.

Summary

• An amazing and successful several weeks of hard work and great care from the LLO/ U of Fl/ Enhanced LIGO team.

LIGO computing and network security (Roddy)

Reported under General Computing, see below

General computing and LDAS admin (Giardina)

Reported under General Computing, see below

Reported under LDAS System Administration, see below

Data analysis & computing (Yakushin)

Storage/Condor/LDAS admin:

Reported under LDAS System Administration, see below

Data analysis:

Reported under Data Analysis activities, see below

Mechanical and Optical Systems (Coyne)

See Advanced LIGO

Controls and Data Systems (Bork)

See Advanced LIGO

40-Meter Interferometer (Weinstein)

• Rob submitted a final draft of the DC Readout Amaldi paper with responses to referee's comments.
• Tobin continues to study the PSL RIN with the instensity stabilization servo on and off.
• Alberto continues to test different designs for his broad-band MC RFAM monitor circuit.
• Andrey continues to optimize the suspension damping gains of ITMX and ITMY by minimizing the XARM rms noise.
• Steve and Tobin have discovered that a particular kind of laser safety glasses that we have been using for 2 years at the 40m (LaserVision glasses with uvex T93 Filter reflective dielectric coatings for IR) are defective. They have very good visibility in comparison with our absorptive glasses, so we have been favoring them. But the dielectric coating degrades (for unknown reasons), thereby providing no protection from laser light. We have collected all 6 of our glasses and gave them to Bill Tyler for disposal. We have notified all site safety officers at CIT, MIT, LHO, LLO, GEO, and ACIGA.
• Steve has measured the IR transmission of all of our other (absorptive) glasses; they were all immeasurable with a 170mW Crystal Laser 1064nm laser.

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Thermal Noise Interferometer (Black)

• This week we measured the seismic noise at the old and new TNI locations. We have been having trouble keeping the instrument locked long enough to take data, and one suggestion was that the new location might have more seismic noise than the old one. It seemed unlikely, given that we only moved about twenty-four feet inside the high bay, but we did move from one concrete slab to another. All indications are that the seismic noise is the same in the new location as in the old.
• We also did some cleaning up and housekeeping in preparation for PMA safety walkthroughs.

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LASTI (Mittleman)

BSC-ISI

• We have started the in-air testing phase of the ISI.
• It looks like stage 1 has some rubbing, since this is the “easier” stage to debug (mechanically) we have moved on to stage 2 testing, which includes the ISI/Quad interaction tests. Most of the last week has been taken up in shaking down the new software; we are using the multi-frequency comb excitation software that has been developed at Stanford. It seems to be working nicely now, so I’m hoping for rapid progress (ever the optimist).
• We had some minor issues with the coil drivers and had to remove one stage of whitening (could get enough drive at high frequencies (>5Hz) otherwise).

Noise Prototype Quad

• Brett been trying to work around the ISI schedule and has been able to make some progress he is estimating 2 weeks more work is needed to get it ready for vacuum insertion. We have scheduled the next SUS-Quad working week/party for January 14-18.

Monolithic Preparations

• We have had two separate groups at Lasti in the last 2 weeks. Helena led another bonding effort in which Marielle, Karen Haughain van Veggel(Glasgow), Danny Sellers(LLO) and Bob LaLiberte(MIT) glued the ears onto the Noise prototype penultimate mass.
• There has also been a group here led by Alistair Heptonstall(Glasgow), including Russell Jones, Mark Barton and Colin Craig building up the welding and fiber pulling machine. They have been slowed somewhat by shipping and custom issues, but yesterday they did briefly test the CO2 laser.
• There are some pictures of the welding intallation on today Lasti ilog

CIT Science Group (Weinstein)

________________

Kipp Cannon:

• Began code review for SGR burst paper.
• Worked in finishing likelihood ratio based coincidence paper.

________________

Joseph Betzwieser:

• For the Crab Frequency domain search, went over new larger parameter space with reviewers.
• Editing Crab Paper.
• Modified targeted search scripts to setup a coherent followup for Powerflux candidate.

________________

Diego Fazi:

• Running a bank-simulation to test the efficiency of the PTF template bank.
• Running a 3-IFO coincident search on the first month of S5 playground data using the PTF filter.
• Implementing a prototype metric for the PTF parameter space.

________________

Igor Yakushin:

• Working on simulations for the first year of S5 for 2-detector networks (3-detector analysis was completed before the LSC meeting; waiting for vetoes and final cat 3,4 DQs to open the box).
• Working on the full S5 H1H2L1-network analysis with the coherent waveburst to get a better estimate of the significance of the equinox trigger.
• Last week attended burst f2f, LSC-Virgo and GWDAW-12 meetings. Gave a presentation at f2f on the status of the first year S5 analysis.

________________

Gregory Mendell:

• Besides attending the GWDAW meeting, my data analysis time for the past week has been spent doing some checks for the calibration team and the CW group.  I am also reading recent papers from the CBC group.

Laboratory Computing (Anderson)

LDAS Software Systems (Maros)

• Work is starting on several optimizations for the diskcacheAPI. The first of these optimizations is the detection of changes to a file system using the statvfs system call (PR#3188). With this optimization, a deep scan of a mount point can be eliminated by the detection that the file system has not changed.
• Also in the diskcacheAPI, the TCL code responsible for the prestaging of frame files has been removed (PR#3232). This functionality is now part of the frameAPI where it uses the SAM API for frame files located on samfs file systems instead of an external system call.
• A resource variable controlling the length of time for the frameAPI to wait for data from the diskcacheAPI has been added (PR#3230). This modification supersedes a static timeout limit.
• Work continues on generating nightly reports from within cmonClient.
• The weekly system testing used version 1.9.144 of LDAS.
• The week long run on ldas-test yielded 7 failed jobs. All were in the datacondAPI not being able to find symbols because data was received too late.

LDAS System Administration (Anderson)

Caltech

(Dan Kozak)

• Checked all frames in the CIT cluster--still only the 5 bad Burst-MDC frames.
• Installed replacement 3510-11 disk.
• Copied Hann windowed SFTs from cluster storage to /archive (CIT) (still need to be published).
• Started configuring LDR to transfer A5 L0 data, but so far haven't gotten it working.
• Configured archiver.cmd for A5 data (LHO/LLO).
• Finished moving tapes & cabinets in Booth with the not inconsiderable help of Jim Covington.
• Reconfigured RAID sets on all 3510s (other than 3510-11) (all as a single RAID 5 with 32K stripe size).
• Checked that it looks like SAM-QFS can handle multiple ACSLS instances.
• Did some work to get the /home1 & /home2 usage statistics plotted again (ongoing).
• Reconfigured the lag plot for A5.
• Ingested last of LHO S5 tapes.
• Pinged Sun again about the morbo crash case (no answer).

(Phil Ehrens)

• Removed "galloping" fans from nodes 64, 99, 109, and 247.  In all cases the diagnosis was made after numerous disk errors were reported. The fans were found to have significant wear to their ferrite rotor elements, causing them to become unbalanced. The vibrating fan induced errors on the drives.
• Replaced failing hard drives in nodes 64 and 247.
• Applied requested patches to Travel Application Request form.
• Applied requested patches to GWIC Wiki.
• A single Data Cache ECC error was logged from node287.
• 5 fans have failed since the fan speed was reduced. Of these, all failed by wear of the ferrite rotor, with no broken blades noted. 

MIT

(Fred Donovan)

• All quiet this week.

Livingston

(Igor Yakushin)

• Made changes to x4500-1 /etc/system to get rid of sata disks disconnect problems, rebooted and reran rsync. There were no more disconnect errors.
• Fixed a few problems with the new version of LSCdqInsert discovered by Keith.
• Working on inserting John's segments.
• Resyncing databases in another effort to revive replication.
• Writing a proposal how to change the segment replication database in the preparation for S6 in light of the problems we experienced during S5: a) when replication breaks (and it happens periodically), to fix it one must often suspend segment publishing at all the sites for several days while repairing the replication; b) poor performance of LSCsegFind; c) scalability issues as the database grows.

Hanford

(Greg Mendell)

• I am working on planning for space for a potential new tape library system for LHO, and the storage of S6 data.

General Computing (Wallace)

MIT

(Fred)

• Optics lab pc install.
• Labview quotes.
• Installed laptop for sf trip to lho.
• Parts return penguin, packing up material from conference.
• Misc gwdaw12 cleanup tasks.
• Misc printer, xp issues. lsc/gwdaw12 conference went well.

Livingston

(Dwayne)

• Kantech upgrade postponed until January 12.
• Ongoing upgrades of Solaris workstations to Sol 10 U 4 and LDAP client, and migration to the new subnet.
• Received another replacement PC, installed software.
• More SEC air handler controls problems.
• Created two new GC accounts.
• Replaced toner cartridges in a printer.
• Updated firmware on the printer in Bonnie's office to fix a problem with PDFs printing with a red background.
• Submitted a ticket with Dell to have an LCD kit replaced on a Latitude D620.
• Other usual/unusual user support requests.
• Cleared spam trap.

Hanford

(Christine)

• Moved more people over to the new mail server.  Still have 4 holdouts that have not moved to the new server so I will not be able to shut down the old server before the long holiday.
• Moved to the new web server.  That seems to be working fine.
• Installed latest updates and patches on computers that were recently upgraded to Solaris 10U4.  Mounted all the remote drives for home directories, ldas data and application server.
• Next week I will be collecting all the old computers from people who received new computers this last FY.  Will also be removing the old disk system and some old computers from the server rack.
• Set up accounts for a new hire.  Loaned him a laptop from the loaner pool until I can buy his computer.
• Helped a user with a problem of jpeg files not associating with the desired viewer software.
• Purchased a Sun V125 to be the new application server.

Caltech

(Mike)

• Worked most of this week switching users over to our new mail server.
• Loaded Ansys 11 and fixed other problems on an Engineering Workstation for Calum Torrie.
• Setup Bert Cresta with VPN accounts for Caltech & LHO, plus installed PRISMPM software to give him access to both site database servers.
• DCC: Rebuilt the nightly process workstation. I had an identical box that I used to swap out the bad parts I needed. Between both computers I now have a decent workstation up and running.
• Working on a procurement issue.
• Other misc. user support and sysadmin tasks.

(Christian)

• 40 Meter: Installed Matlab and Mahematica on visitors’ workstation.
• Migrating users to new email server this week.
• Did an inventory on printing supplies.
• Testing Microsoft latest security patches.
• Updating E. Bridge display case.
• Other misc.: Continued onsite software/phone support.

(Veronica)

• LIGO:  Installed new web content at the gateway page and homepage. The new pages have received positive feedback.  The redo of the internal bulletin board.  Other web updates.
• LSC:  Installed a webpage of presentations of the last meeting, posting the talks as processed by DCC.  Working on the redo of the website.

(Larry)

• Finally, wrapped up couple of the old P-card reconciliations. Also, finished up this month's P-Cards. Getting quotes for new laptops, desktops and working on a new server configuration for the DCC. Finalized a license renewal and working on two more for different groups.
• Installed some more h/w in the server room -- mostly to get ready for a swap out of equipment between racks.
• Working on an edge switch setup. It is now ready for testing.
• Still working out logistics for the all hands meeting for next month.
• Assisted a number of users in getting their mail service moved over to another server.
• Worked some minor printer issues. Worked with Mike in installing another new printer.
• Spending more time going over reports/logs.
• Regular user assistance, mostly with 3rd party applications.

(Melody)

• LAAC: working on Nergis' wiki requests. Working on the thesis topics table using the modified data entry screen.

Advanced LIGO and Supporting R&D (Shoemaker)

Advanced LIGO Management

• No report.

Advanced LIGO Systems

Modeling and Simulation

From: Hiroaki Yamamoto

Static IFO simulation (Hiro, John)

• John completed the first version of the mapping function to convert the phasemap data to the format FFT uses with proper low pass filtering. Hiro is working to integrate the code in SIS to analyze if the effect of the orange peel with spacial frequency is problematic or not.
• Hiro reworked the effect of the curvature mismatch (ITM and RM) effect on the performance, Now the analysis uses the new (may be already obsolete) design of the stable recycling cavity and the low finesse optics parameters.
  The results were presented at the weekly COC meeting.
  Regarding the signal itself, the merit of the stable cavity is compensated by other factors, like the change of the diffractive loss in the arm or the diffractive loss in the Michelson cavity. As to the SB, the the mode resonating in the Michelson cavity is much more stable than the mode in marginally (LIGO I like) stable cavity.
• It was concluded that the wedge effect would not be included in the SIS, because the effect calculable using SIS is O ( (difference of thickness from one edge and other / optics aperture)^2 ) ~ ( (6mm / 37cm)^2 ) = 3 x 10^-4.
• SIS got various code improvements and the new codes were deposited to CVS, and the documentation was updated.

Mechanical Simulation for advanced LIGO (Sany and SLU team)

• Of (MC1+MC3) and MC2 pos DAQ OSEM signals (recorded previously at LLO). The computed coherence was fairly high (>0.9) in dc to ~2 Hz, and then gradually decreased to ~0.7 at 3.5 Hz (except for the small optic's resonant frequencies and their harmonics). At frequency above 4.5 Hz, the coherence was substantially zero. As a continuation of this study, this week I looked at the phases of (MC1+MC3) and MC2 pos DAQ OSEM signals. The observed phase difference has the following features. (1) dc to 0.7 Hz: the phase difference starts off with zero at dc, increases linearly to 10 deg at 0.5 Hz, and stays at the same level till 0.7 Hz. (2) 0.7 – 2.3 Hz it is noisy (most likely due to the small optic’s and HAM stack resonances) around the same level as 0.5 – 0.7 Hz. (3) at 2.3 Hz it sharply increases to about 30 deg, decrease linearly to zero at 4.5 Hz, and keep increasing at the same slope till 5.5 Hz where it becomes totally noisy (most likely because the coherence is very low). The feature at 2.3 Hz seems to be due to the stack’s second U-U transfer resonance.

Prestabilized Laser

From: Peter King

• The 35-W laser for LHO is ready.  A quick measurement made with a
  pre-modecleaner yielded 92% in the fundamental.  The measurement could be
  improved upon with better mode matching.
• There is some concern with the lifetime of the 2-W NPRO master oscillator;
  one laser was observed over three and a half months to degrade by the
  annualised rate of 20%.  InnoLight suggested derating the NPRO.  As far as
  InnoLight knows, we are the only customer that runs their lasers
  continuously.
• The high power stage performance has unexpectedly changed.  The
  laser that was producing 180 W just before and for a month after the LSC
  Meeting is now only producing 165 W.  Various components have been checked
  and replaced.  The cause is still unknown.  The injection locking
  electronics are also being worked on.
• An high power pre-modecleaner was tested (finesse of about 50).  With 165 W
  in, somewhere between 120 - 130 W throughput.  Measurements of the RF
  intensity noise suggest that the finesse is about right.
• Work for the FDA accession number, allowing the observatory lasers into the
  country, has started.  I received some information about applying for an
  exemption and when the paperwork has to be submitted for next year.

Control and Data Systems

• No report.

Seismic Isolation

From: Ken Mason

Single Stage HAM Seismic Isolation Assembly and Test

• Corey, Myron and Stephany will be traveling to LLO on January 2nd to assist in the assembly of the Enhanced Ligo isolation system.
• The packaging of the bellows for shipment was torn when it arrived at Livingston and Hanford. Kyle and Brian O'Reilly are working on a plan to clean the bellows prior to bake.
• Fabrice has redesigned the installation fixture so that it is made of steel weldment. instead of Bosch tooling. This has cut the cost by 30% and delivery time by 1 week.

Suspensions

From: Janeen Romie

Advanced & Enhanced LIGO

• Output Mode Cleaner: The top blade bake fixture parts are with Southern Enterprises and will be picked up Jan 2nd. Connector brackets and other EQ stop brackets were sent to Bob Taylor for cleaning and baking last week. He has the OMC parts for cleaning and baking now. Norna reported that room 056 has been cleaned and is ready for clean re-build of the OMC in January. The structure should be done with it's chemical cleaning, called Brite-Dip, by tomorrow and will be shipped back to Caltech next week. Bob confirms that he can clean and air bake the structure. He has the Birmingham osems for this assembly and is cleaning and baking them. Chris has submitted the OMC structure drawing for review.
• Recycling Mirror Suspension: Greer has submitted a preliminary draft of the RM structure for review.
• Input Mode Cleaner: We are working on a document list for the IMC PDR. Mike M is looking at the IMC structure with respect to stiffening it up.
• HAM Aux Suspensions: Derek has received the Matlab code for a single pendulum suspension.
• Quad: Working with Norna on coordinating personnel support of quad work at LASTI.

From: k mailand kmailand@ligo.caltech.edu

Adv. LIGO

• Assembly frame and for Sam's OMC bench is complete, the shipping container for carry on transportation to the site,  is in the CIT shop.
• The aluminum OMC frame structure is in process at the Brite dip vendor,
  we should receive it next week.
• The FTIR test of the etch cleaning process sample of the Brite Dip process for Calum / Janeen re. welded aluminum structure cleaning, are complete  and show no problem contaminates.
• The RGA test is completed and the results will be in today.
• I have done two suspended manifold baffle designs for Mike Smith, for e and a LIGO.
• I have two samples from local water jet cutters for the baffle and beam dump black glass cutting they will do a sample part this week.
• Testing the faraday 4 wire style damper is in Phil Willems lab, is in progress.S

Core Optics

From: Helena Armandula ahelena@ligo.caltech.edu

Advanced LIGO Coatings

CSIRO - Hafnium Oxide Coatings

• In order to prevent damage to the HfO, they have limited the annealing to 300 C for samples with this material. We received:
  • For Glasgow:
    • 3  silicon cantilevers with 0.5 micron of HfO2 on them annealed to 300C for 24 hours
    • 1x 3" thick, with 30 layers of HfO2/SiO2 annealed to 300 C for 24 hours
    • 1 x 3" thick,  with 30 layers of 70%HfO230%SiO2 - SiO2 annealed to 550 C for 24 hours

Also, a set of silicon cantilevers with 0.5 micron of TaO on them and 4 different annealing steps applied to them.

• For Caltech:
  • 1 x 3" thin and 4 x 1" witness samples with 30 layers of HfO2/SiO2 annealed to 300 C for 24 hours
  • 1 x 3" thin and 4 x 1" witness samples with 30 layers of 70%HfO230%SiO2 - SiO2 annealed to 550 C for 24 hours

These substrates are being inspected at Caltech at this time.

Auxiliary Optics

From: Michael Smith

ADLIGO

• IFO LAYOUT: Mike is compiling the available ranges of mounting locations for the recycling cavity optics to assist in determining the power and signal recycling cavity lengths.
• SLC: Mike has begun to update the SLC Conceptual Design doc by adding the new drawings showing the locations of the ghost beams and beam dumps and baffles based on the new ZEMAX IFO layouts.
• CRYOBAFFLE/MANIFOLD BAFFLE: Mike and Ken developed a concept for combining the suspended cryopump baffle within the manifold baffle.

Input Optics

From: David Tanner

LLO team - Dave, Guido, Muzammil, Antonio, Kate, others:

• The eLIGO Faraday is installed and the doors are on HAMS-1 and -2. The beam seems to be going where is should go.

LHO team - David, Volker, Kate:

• The eLIGO Faraday is installed in the optics lab. Measured parameters:

  isolation: 52 +/- 2 dB

  s trans   -36 +/- 2 dB

  transmission: 96.8% +/- 0.8%

  double transmission (input - mirror - refl port) = 93.7% +/- 1.2%

It's nice that the double transmission is the square of the transmission....

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For additional information about this report, contact Albert Lazzarini or Phil Lindquist