Weekly Report for Week Ending May 29, 2008

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 & Project

Past Weekly Reports

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LSC Issues (Reitze)

• The second S5 paper, "Beating the spin-down limit on gravitational wave emission from the Crab pulsar", was submitted to the ArXiv today.  It will appear on astro-ph on Sunday evening.  This is a 'highlight' result for the LSC, and several LSC groups will issue a press release on Monday to accompany the submission.
• The second L-V meeting of the year will take place June 9-12 in Orsay, France.  The focus of the meeting is data analysis.  The entire meeting (main session and f2fs) will have EVO connectivity for remote participants.
• The LSC Education and Public Outreach group presented a poster on LSC outreach activities at the International Year of Astronomy Symposium at the AAS meeting in St. Louis last week.

LIGO Laboratory Administration (Lindquist)

FINANCIAL SYSTEMS (Oracion)

• Created blank template for OPs monthly financial report for the month of May 2008. Started expenditure and budget review for report.
• Submitted five cost transfers to project accounting, two of which are for Advanced LIGO "pre-award" costs per ACR-080002.  The cost transfers were pre-approved by project accounting prior to submission.
• Requested various expenditure type corrections.
• Provided data/charts for End of April 2008 report.
• Financial reports can be found at: http://docuserv.ligo.caltech.edu/~fireport. (For passwords contact Karl).

Quality/Safety (Tyler)

AL:The annual safety audit of LLO took place this week on 29, 30 May. No serious issues uncovered. The LLO team is to be commended for a good job.

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

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

Enhanced LIGO commissioning

• IOO work continues. People worked hard to understand what seems to be a smaller-than-expected power throughput from the PSL table to the bottom of ISCT1 (REFL) periscope. Many measurements were made but nothing conclusive yet. The best value measured so far is about 58 %. Due to this, we still haven't operated the MC with full 35W power.
• The above performance is despite the fact that the mode cleaner has an excellent visibility of 97%, and the mode cleaner pole was measured to be slightly better than it was in March 2008.
• The 35 Watt laser was accidentally shut down when a 5 amp 24 volt fuse blew.
• New modulation depth etc. were posted due to the change in the laser/EOM/ electronics.
• Though much of the heavy assembly work has already been done, ISI work continues. Table was leveled and some electronics work started.

Astrowatch

• It was found that H2 is suffering from acoustic peaks in AS3. Expect acoustic tuning of the beam position on the table.

Outreach (D. Ingram)

• The quantum for a LIGO field trip is the school bus. During the last week LHO has received three 3-bus visits, one 2-bus visit and three 1-bus visits. This represents about 500 visitors.

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

General Operations (Rusyl Wooley):

• We put the 84" covers back on HAM6 and began pumping down that chamber as well as opening GV1 & GV2 in order to begin commissioning exercises again.
• We are also going through our annual safety audit this week.

LLO Outreach (Deborah Muhammad):

• Developed "snack" materials for teacher workshops.
• Developed programs and made preparations for 3 teacher PDs week of June 2-7.
• Conducted 1 school field trip.
• Preparations & scheduling for summer teacher workshops.
• Scheduled and conducted public tours for Friday.
• Uploaded student field trip pictures to share folder for website use.
• Purchased supplies for teacher PD.
• Reported final count for docent visits (Cohort 1).
• Managed SEC documents: Archived folder from (shared) Active File.
• Prepared PowerPoint Slides for LSC presentation.
• Conducted safety walk-through in SEC.

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)

• Youichi Aso has arrived, and will be working on the new 40m upgrade. Please welcome him!
• Caltech undergrad Caryn is developing MISO filters of different orders, with various sampling rates, for adaptive noise cancellation.
• The mode cleaner alignment has been a bit off since the computers went down last week. Rana worked on the alignment, and then John fiddled with the input periscope, to maximize transmission, minimize reflection, and get the beam back on to the WFSs.
• Rana has been working on improving the PMC mode matching and transmission.
• Joe and Andrey installed new GigE 24 port switches on our electronics racks, in preparation for rebuilding the whole ethernet network.
• Tobin is visiting. He set up an EPICS gateway server on our new gateway computer, and moved the NDS Proxy program onto it.
• Steve completed the installation, alignment, and centering of the new ETMY oplev after the old laser died.

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Thermal Noise Interferometer (Black)

• Tara continues to work on optical levers, and Greg is designing the next iteration of the photothermal experiment.

From Akira:

• This week I made some measurements of the seismic noise around the vacuum chamber and on the optics table of the TNI. I discovered and fixed a problem with the wiring of the motorized mirror mounts. I also did some work on the alignment.

---

LASTI (Mittleman)

BSC-ISI

• We are working to seal up the BSC and pump down. Everything on the ISI appears to be working (YEAH!) and the Quad is hanging free with the local damping running. Six witness L4C geophones have been installed on the optics table. We have fixed up a preamp for them, we still need to make up some special cables before they can be plugged in.
• I think that we have found a minor problem in the anti-aliasing chassis that appears to be associated with overheating on the board.

Fiber Pulling and Welding

• Further work has been done on shaping the CO2 beam prior to putting it down the articulated arm.  An automated setup to measure beam shape has been made with a beam blocker on a motorized translation stage. Positional information is fed back to labview from an encoder and measurements are taken from a power meter by a labview script.  It has been shown that the beam diameter can be controlled and reduced along a path length greater than the articulated arm length.  Some graphs may be found here (requires pasword).

CIT Science Group (Weinstein)

______________________

Pinkesh Patel:

• Preparing to go visit Xavier for a week in Milwaukee.
• Wrote an Auto-Damping Script for H2.
• Hunted noise sources in H2 for astrowatch.

______________________

Antony Searle:

• Continued reimplementing parts of WIMPORTANCE in C++.
• Worked on Orsay presentation.
• Finalising major Bayesian paper with Patrick and Massimo.

______________________

Chad Hanna:

• With Amber, Joe and the Calibrators, I have been preparing for an h(t) review call next week. We have made progress at automating the identification of times when h(t) and h(f) disagree. We will use this to make a data quality list.
• I have committed a host of changes to pipeline code in glue and lalapps to integrate grid submission with pegasus into inspiral work flows.
• Britta, Kent and I have been working with the USC/ISI Pegasus team to add features to Pegasus which should finalize the first stages of integration.

______________________

Diego Fazi:

• Investigated and tracked down the bug in the head of LAL that caused injections not to be made when an external injection file was specified.
• Wrote a fix for the code which is still under discussion.
• Followed up missed injections at low effective distance for the 1-month PTF injection run.

______________________

Kent Blackburn for the Grid Computing R&D Group:

GRID APPLICATION DEVELOPMENT

• Wrote agenda and led LIGO-Pegasus and OSG-USERS telecon. Wrote up and distributed minutes for LIGO-Pegasus telecon.
• Attended DASWG, Inspiral Coding, OSG-USERS and INTEGRATION telecons.
• Einstein@Home Activities on the OSG (E@OSG):
  • Currently running E@H application at TTU, BNL_ATLAS_1
  • Trobleshooting issues at UCSDT2, UWMilwaukee with support from site administrators and E@H developers
• Binary Inspiral IHOPE Activity:
  • Testing Chad's test script SPEW on ldg (Pass on cit), CIT_CMS_T2 - (fail at data transfer) will debug
  • Ran ihope on ldg with playground via pegasus-->fail
  • Ran ihope on ldg with playground run on OSG (CIT_CMS_T2) fail (troubleshooting with Chad)
• Working with ISI Pegasus developers to enable them to run LIGO similified workflows based on the binary inspiral workflow on  the LIGO Data Grid and the Open Science Grid.

OSG INTEGRATION AND VALIDATION TESTBED

• Completed OSG 1.0 software stack testing against LIGO applications on the Integration and Validation Testbeds.
• Documented results for participated VOs on the OSG Twiki.

GRID MANAGEMENT

• As a result of positive results on all OSG Testbed sites, signed off as the LIGO VO contact that LIGO approved going forward with the 1.0 software stack for deployment on the OSG Production Grid.
• Held meeting with ISI Pegasus developers to prioritize and define schedule for several functional enhancements that would facilitate the development of new binary inspiral applications, while also simplifying the complexity exposed to end users, e.g., scientists.
• Drafted revised job description for Grid Application Developers.
• Reviewed new pool of Grid System Administrator applicants. Contacted top candidate but learned that the circumstances of the position did not match up. Have a few more to go through and contact.
• Worked with the CompComm to prepare for tomorrow's telecon with the OSG. Topics will very likely include running E@H on the OSG and request to OSG to place Britta in leadership role for the E@OSG effort.
• Continued to work within the SCAT subcommittee on issues of weak user certs and issues with those CAs that were victims to the openssl vulnerability. Currently no word from GermanGrid CA on impact to their user community AND the issues with UK eScience CA users not being able to gsissh onto the LDG after UK eScience replaced their weak root certificate. Reported status to the CompComm in weekly telecon.

______________________

Drew Keppel:

• Working on the review for the S5 1Yr Low Mass CBC search.
• Running / posting information on all the post-processing that is done associated with the search.
• Preparing to compute the final upper limits for the search.

______________________

Amber L. Stuver:

LIGO Research

• Continued working on the h(t) validation.  All of the infrastructure for applying SLOPE is in place and I am starting to run it over the entire S5 data set.  There will be a time domain calibration meeting with the reviewers next week.
• My follow-up work on candidate GW events being physical was brought up at the burst group telecon and they are also interested in this work.  I will be giving a talk on this to them at the Orsay meeting.

SEC Work

• Gave control room tours to about ~15 students.

Other

• The FGSA voted unanimously to propose a partnership with the AAPT Committee on Graduate Education in Physics and I've have sent out the proposals.

______________________

Anand Sengupta:

• The condor job for the last month of s5 2nd year with high mass EOB templates finished. Generated plots and preparing an entry.
• The condor job for band pass templates has finished. Many plots are now available <http://ldas-jobs.ligo.caltech.edu/~anandss/testTaperFunctionEOB/>.
• Modified code to inject band-pass signals. Baby sitting condor job for EOB injection run.

______________________

Gregory Mendell:

• My data analysis time at the moment involves reviewing and discussing aspects of various searches with members of the CBC and CW groups.

______________________

Kipp Cannon:

• Working on some calculations related to gravitational wave detection through radio interferometry.
• Continued with on-going S4 string search review.
• Mostly wrapped up S5 1st year SGR flare review.
• Telecons:  daswg, inspiral coding.

Laboratory Computing (Anderson)

LDAS Software Systems (Maros)

• The new frameCPP code introduced some errors. It was known at the time of the commit that there was no support for frame files written to the version 3 or version 4 frame specification. This resulted in many of the System tests failing. These tests have been flagged so they can be skipped while efforts are under way to once again support these versions of the frame specification. Also, a large memory leak was introduced. It was isolated to the createRDS command. Work is underway to solve this.
• Efforts also continue on parsing of test report responses.
• No formal System testing of LDAS was done this week. Instead, efforts focused on identifying which system tests still require version 4 frame files and identifying which jobs caused memory leaks in the frameAPI.
• The system ldas-test has now resumed with running week long tests. With the jobs known to be incompatible with the current version of framecpp removed, the system performed as expected.
• The latest version of DB2 is being tested on ldas-suntest1. After several reconfigurations of the system, it appears to be running jobs stably.

LDAS System Administration (Anderson)

Caltech

(Dan Kozak)

• Rearchiving data in /backup to T10KA tapes at CIT (ongoing).
• Working Sun cases pertaining to opterondata-cit: ssum, a panic and mpxio failovers.
• Filed case with Sun regarding raidctl's infinite loop.  Got instructions to take the machine down and look at the hardware RAID from the BIOS level--still waiting on a good time to do that.
• Did lots of work moving LLO's /archive to a 6140 and it's SAM-QFS MDS box to opterondata-llo and then restarting services.
• Updated grid-mapfile for Scott Koranda.
• Gave Lisa instructions on how to fsck /fb0_frames at LLO.
• Relabelling tapes at LLO.

MIT

(Fred Donovan)

• All stable; morel.mit.edu (einstein@home mirror) disk full, needs another one; a bit more work on monitoring scripts - (smartd bash scripts used with gmetric).

Livingston

(Igor Yakushin)

• SAM/QFS was upgraded on dataserver and gateway.
• Opterondata-llo is upgraded to Solaris 10 update 4.
• Moved a dual port 2Gb HBA from dataserver to thumper1.
• /archive migrated from T3s to 6140 [with Dan's and Stuart's help]; no T3s are in use at LLO now!
• /home migrated from 3511s to x4500 [with Dan's and Stuart's help].
• Fixed nodes 3 and 6; node 4 appears to have more serious problems than a failed disk; there are still several nodes with bad disks.
• Requested GC address for thumper1; for now temporary reusing ldas-pcdev2 address.

Hanford

(Greg Mendell)

• I am continuing to work on a number of tasks, including the planned LDAS disk upgrades at LHO, a special S5 RDS rerun, Condor test DAGs for the pulsar group, h(t) generation, and the next release of the LDG Client/Server packages.

General Computing (Wallace)

MIT

(Fred)

• Set up two computers (xp/linux dual boot) for summer students.
• More mac address (arp) issues on lan.
• Some licensing issues.
• Server 2003 install (backup for enoki)
• Added second disk to Ken's pc.

Livingston

(Dwayne)

• Kantech controller installations last Saturday, to be continued this Saturday.
• Reboot kantech server.
• Setup EVO meetings for "face-to-face" interviews of Safety Engineer candidates.
• Received new laptops for Mech. Engineers, various installs. One was incorrect system, RMA'd that one.  New one received today.
• Various patching on different systems.
• LLO VPN appears to be working well.  I have been using it at home with only a few noticeable glitches.
• Created a couple Inventory Control Systems accounts for test users.
• Returned some failed disks to vendors.
• Other usual/unusual user support requests
• Cleared spam trap.

Hanford

(Larry)

• Ordered more EVO equipment for the Observatory.
• Working on spam filters.
• Misc. end user support.

(Mike)

• Continued work on freeing up expired DHCP numbers.
• Clearing up spam/undeliverable that is trapped in the spool on bepex.

Caltech

(Veronica)

• LIGO: GWIC website -- Assisted Stan with web issues. Ongoing support of PAC meeting website. More work on the LIGO Travel website. Other web updates/user support.
• LSC: Work on the ligo.org redo picking up. Updates of the database of technical papers, other web updates.
• CaJAGWR: Taped and processed for streaming the video of the last talk.  Set up an EVO broadcast. Website updates /user support.

(Mike)

• M79: Transferred old NTSRV backups to an archive backup drive to get ready for end of month backups.
• Continued work on ligo.org's replacement server. I almost have this server wrapped up.
• Loaded an additional server to replace cheetah. This is an on going project.
• Rack mounted some equipment on our server room 18 B/A.
• Worked on becrux which was one of mail servers. Larry has eliminated most of the mail services to get this server out of the loop and retire this server.
• Some user support getting the last users off becrux, and moving them over to gacrux.
• Worked with Christian on setting up a EVO workstation in ECR.
• Other misc. user support and sysadmin tasks.

(Melody)

• New DCC: Continuing with answering the committee's questions regarding DocDB. Continuing with trying to use google (customized search) to search through the DocDB document contents. So far, the documents are not being found (by google's search) even if the access logs show that their crawler have indexed the documents. This doesn't seem like a solution for the new DCC's content search because the time lag is too long. Installed TRUC and XOOPS to see if either can be used for tracking the requirements.
• Testing EVO with the Mac laptop: the audio isn't working.

(Christian)

• Marilyn Wright - working on transferring all of Marilyn’s software and data file to new laptop.
• Configured new workstation to be use with the EVO system in the ECR conference room.
• Working on configuring new Windows XP 64 bit system.
• Minor tweaks on the WSUS backup server.
• Other misc.: Continued onsite software/phone support.

(Larry)

• Working and worked a number of procurements. Tracked down a number of items that are still in transit. So far it doesn't appear anything has been lost, just delayed. Delivered a number of items and still working on getting items received put in their permanent locations. Still a number of workstations to be ordered for different users. Started work on getting information for the network upgrade scheduled for this fall. Working on a couple of s/w licensing contracts.
• The EVO testing continues. Still no luck in finding a solid solution for the Mac units other than the Phoenix Solo setup, but we are still trying. The clearone and phoenix units we have been using for the conference systems have worked well on the PC's. It has been decided to install a PC with a phoenix or clearone unit in each of the conference rooms. Just one room left to install, however we are having an issue with the computer in the SCR. Hopefully, some training will resolve the problem. The loaner EVO system has been getting quite a bit of use for meetings being held at other locations here on campus.
• Finally, killed most of the mail services on the old servers. Working on the logistics to get the last unit completely out of the loop to where the new servers will not have any dependency on the old h/w.
• Worked a number of web service issues. The gwic.ligo.org server is now on-line.
• Worked a couple of different issues for the DCC.
• Usual end-user support, meetings and paperwork.

Advanced LIGO and Supporting R&D (Shoemaker)

Advanced LIGO Management

Advanced LIGO Project Management

From Carol Wilkinson

Project Controls

• Project controls has collected information on corrections needed for the project’s first six weeks of reported time. A request for a cost transfer from operations to project accounts will be sumitted.

Procurements

• A meeting with the NSF financial officers for grants and awards was held on Friday, May 29 to discuss the terms and conditions of the project Acquisition Plan. The NSF has accepted the plan and is working through the various procurements in order to grant pre-approval for purchase.
• The contract for MIT sub-award is close to being awarded. It has already been approved by NSF.
• Contract for the University of Florida Advanced LIGO effort is being processed. It needs NSF approval before it can be awarded.
• RFQ’s for several HEPI mechanical items are nearly complete and will be released.
• Ed Jasnow has worked with the NSF on a standard set of terms and conditions that will be part of each RFQ/contract.

Progress Updates

• Schedule progress updates were due on May 28. Status reports will be available on June 3, with variance reports from subsystem leaders due by COB June 4.

Meetings & Reviews

• The next monthly status meeting will be on Thursday, June 5 at 8:30 AM PT.

Advanced LIGO Systems

From: Dennis Coyne <coyne@ligo.caltech.edu>

From: Peter Fritschel <pf@ligo.mit.edu>

Operations Activities

• Thermo-optic noise calculation: Matt Evans included a thick-coating correction factor to his Bench functions for thermo-optic noise (a small correction). The finite-mirror correction factor for the coating thermo-elastic term is being coded up by summer undergrad Sam Wald.

AdL Project-Funded Activities

Reviews:

• Review committee participation in the FMP fabrication readiness review for facilities and clean rooms.

    For a list of reviews, see the main AdL wiki page

Technical Review Board (TRB):

• Gold coated TM TRB:
  • working on calculation of modal damping to compare to UWA calculations: resurrected model used in Hans Bantilan's and Bill Kell's PI study, refined the mesh, checking convergence and difference between FEA generated strain energy and strain energy calculated from strain field. Extended the matlab code uffread.m to read stress and strain output from the universal file format generated from I-Deas finite element analysis.
• see the TRB log

Vacuum Review Board (VRB):

• Nothing significant to report.

Configuration Control:

• Nothing significant to report.

Design:

• AOS/SYS issued optic coordinates and cavity lengths for the small wedge angle (~0.08 deg) layout for the H1/L1 interferometer. The small wedge angle layout for the H2 interferometer will be released soon for review.

Interfaces:

• Nothing significant to report.
• See the RODA status page and the Interface Control page.

Modeling and Simulation

From: Hiroaki Yamamoto hiro@ligo.caltech.edu

Static IFO Simulation (Hiro)

• Hiro setup a Wiki (http://ilog.ligo-wa.caltech.edu:7285/advligo/MITFFT08) for the people who want to use the FFT program to simulate the LIGO I or eLIGO mode matching. A getting started document (T080131) and a starter kit are provided. The fortran source code is also downloadable. 
• This is based on the B. Bachner's FFT program. It has been modified to work with thermal effects and to accommodate LIGO realities. The new FFT program, SIS, is not yet capable of simulating the entire IFO yet, so this old FFT is made available.
• A simple case result is shown in the web page showing the effect of the mode mismatching on the reflected power shape. The result is compared with the measured shape observed at LLO.
• SIS code modification still going...

Mechanical Simulation for Advanced LIGO (Sany and SLU team)

• Made some progress in the e2e AdvLIGO Input Mode Cleaner (IMC) model. Our recent modification on the frequency servo filter reduced the frequency noise of the IMC transmitted light as expected above the crossover frequency (60 Hz), but increased the frequency noise at f<1 Hz. This week, by increasing the IMC length control gain, we succeeded in reducing this frequency noise at f<1Hz to the expected level. However, this modification has increased the frequency noise near the crossover frequency. Will continue the servo filter modification to suppress this problem.

Facilities Modifications and Preparations

From: John Worden <worden_j@ligo-wa.caltech.edu>

• The first meeting of the review committee was held this week. Renovation plans, clean room plans, and associated budgets were discussed.

Prestabilized Laser

From: Peter King <pking@ligo.caltech.edu>

Operations

• I am working on the laser incident threshold document, having decided to back track on setting one number for all wavelengths.  This is proving to be a bit impractical.  However I have the numbers for 1064nm.  I think I will sort out the other wavelengths if the LSSC agrees to the proposed limit for 1064nm.

Project

• With help from Rich and Chub, I have been gathering pricing information for the various components for the intensity stabilisation photodetector. Some mechanical parts for a prototype photodetector have been fabricated at the AEI.

Control and Data Systems

From: Rolf Bork rolf@ligo.caltech.edu

AdvLigo Development Phase

Timing System (Szabi):

• Ongoing work on documentation, tests plans and coding.
• Paper draft on radiation pressure calibrator based timing/phase calibration performance is under team review.
• Timing distribution system's Master/Fanout FPGA programming is converging.
• Timing distribution system's Slave revB hardware is getting assembled, I/O daughter board is being manufactured, and the timing comparator daughter board revB shall be sent out to manufacturing soon.

DAQ / CDS Infrastructure:

• All but one of the DC power prototype solutions are in house and a testing program has started. During Richard McCarthy's visit to CIT, we will work more on this.
• Loaded and ran realtime code on new Sun 4600 computer with 16 CPU cores. Initial testing looks good and will continue to load it up over the next week.
• Working on docs for DAQ PDR. I have asked Vern to set up a review for July 16.
• Realtime code generator user's guide - 90%
• Realtime software sysadmin guide - 40%
• I/O Chassis design and testing - 60%
• Software Development Plan - only started
• ADC issues: digital output locking at zero when analog input was overdriven. General Standards has analyzed the problem, has a proposed repair, and is in process of producing a test ADC for evaluation. A competitive ADC board from the SemiValley company is expected after June 16, for comparison and evaluation.

ISC:

• RFPD for AdLIGO is being prepared for prototype evaluation at one of the observatories. This has taken a back seat to preparations for the LHO OMC.

PSL:

• I/O chassis, timing and AA/AI chassis delivered to AEI to support PSL work.
• Assembled a distributed CDS for AEI with 2 FE computers and 1 Framebuilder. System is up and running, with code running on two cores of the first FE computer and one core of the second. Models will continue to be developed by AEI staff for PSL and Diagnostic Bread Board controls/monitoring.

SUS:

• Finishing requirements document for UK Triple Suspension Electronics.

AdvLigo Construction Activities

SUS:

• Continue work on satellite box amplifiers and whitening filters test stand definitions and designs, parts selection.

ELIGO Activities

• QPD Whitening Module has been sent back to LLO for field testing after bench testing revealed a sensitivity to low supply voltages.
• Hardware shutter has been constructed for the LLO OMC. Testing is underway and we will be shipping the unit to LLO this week barring any difficulty.
• Alex is continuing to work on the ELigo DAQ configuration, with testing on going at the 40m lab. Target is to try and install at LHO around June 26.
• Working with Brian Lantz to get polyphase FIR filters running for ISI controls.
• Finishing design and testing of TCS preamplifier circuits and development.

Seismic Isolation

From: Ken Mason kmason@ligo.mit.edu

• The apparent rubbing that was holding up the start of characterization of the BSC LASTI ISI turned out to be spurious signals from the position sensors – they may be damaged, TBD. At any rate, work can now progress.
• Project:  HEPI procurements can start, specifically for the Maraging double-helix springs. The procurement readiness review team has asked for some additional information on some of the other long-lead items before procurement can proceed; those are being addressed.

Suspensions

From Janeen Romie and Norna Robertson

(romie_j@ligo-la.caltech.edu, nroberts@ligo.caltech.edu)

Operations Work

HAM Suspensions for Advanced & Enhanced LIGO:

• OMC: We are still experiencing problems with blade delivery. The company is not able to keep to the tolerance required on the radius of curvature. We have asked them to go ahead and produce them and we will characterize them. We are getting spares made and hopefully within the total number received we will be able to pick suitable ones for use. However it is possible that some rework will be needed which could delay us further.
• RM: Nothing significant to report.

BSC Suspensions for Advanced LIGO

• We are gearing up to get things ready for the monolithic suspension. Alastair is continuing work on developing the welding system at MIT, in particular getting the optics and associated parts sorted out for delivering the right size of beam through the articulated arm. Extra parts are being made at Glasgow. Justin has put together a list of items which will/might be needed at LASTI for the monolithic assembly and has called a brainstorming meeting for next week to go over this. Garilynn has informed us that the compensator plate will not be ready to install before August due to getting a gold coating on its barrel. It is therefore not clear whether we will do an ETM (with end reaction mass in the reaction chain) or ITM ( with CP in the reaction chain) style installation as the first one. We will look closely at the schedule after we have tried a test monolithic suspension (metal masses with glass inserts) in a few weeks time, when we will have a better idea when the first full monolithic suspension will take place. Last week we also discussed the procedure and timing for installing the upper intermediate mass (UIM) in the lower assembly - basically should we do this before or after the monolithic parts are put together. We agreed that we would stick to original plan to have the UIM in place before the assembly of the penultimate and test mass to gain experience of the baseline procedure. (The alternative had been suggested as a way to work in parallel to allow more time with the ISI +quad before pulling out the lower section of the quad from the tank.)
• Norna talked to Giles Hammond (Glasgow) and Clive Speake (Birmingham) on hysteresis effects while in the UK. Giles has lined up a summer student to carry out some investigations starting with looking at stress/strain relationship for the type of wires we have been using, and this student may continue with further investigations during the next academic year.

Project-Funded Activities

• Norna has just returned from the UK. During her visit she met with colleagues at Glasgow, Rutherford Appleton Lab and Birmingham to review progress on various aspects of the UK funded suspensions program and related topics.
• At Glasgow she met with Ken Strain. Among the topics covered were:
  • Training on monolithic assembly: Ken noted that the masses with glass inserts makes a good training facility and should be kept together.
  • The second CO2 laser which UK agreed to supply for separate welding facility (the first one will be used for pulling): this will be forthcoming.
  • Hysteresis investigations: see above.
• At Birmingham she met with Alberto Vecchio, Stuart Aston and Ron Cutler.
  • She discussed the schedule on electronics delivery with Alberto. The next delivery will be the electronics ("pre-production" version) for the two test stands for BSC assembly (for LHO and LLO) and they have in place a schedule aimed at an autumn delivery. Timing of reviews which are needed before start of final production was also discussed.
  • Stuart showed her the facilities for making the BOSEMs and discussed the recent work to track down some variability seen in the photodiode current of assembled units, probably an alignment issue.
  • Ron showed her examples of the top mass, upper intermediate mass and penultimate mass electronics units, the designs of which he is modifying in response to Jay Heefner's reports.
• At RAL she met with Justin Greenhalgh and Joe O'Dell and covered several topics including:
  • Modifications to the design of the sleeve and associated parts so that it can be mated to Ken Mailand's 5-axis installation tooling. (Calum Torrie joined in by telecon.) This will allow for moving the whole quad within a BSC chamber for small movements, and also could serve to help install the sleeve.
  • Beamsplitter. She saw the prototype which is partly assembled at RAL. Several items are still outstanding. One is the design of stays for stiffening the structure. A second is the redesign of suitable clamps in the light of increasing one of the "d' distances to raise the pitch frequency (in the same way as has been agreed for the quad suspension). Training on the beamsplitter suspension at RAL was also discussed and it was agreed that Norna would make a formal request that RAL provide training of LIGO staff on assembly and alignment of the prototype beamsplitter suspension at RAL, details to be worked out later.

Core Optics

From: GariLynn Billingsley <Billingsley_G@ligo.caltech.edu>

Project

• The NSF meeting is the only progress we've had on project.

Development

• Possibly the lowest scatter we have measured on a LIGO optic http://www.ligo. caltech.edu/~lzhang/LLO/sm1_tis_1.pdf.
• This is a 2" steering mirror taken out of LLO, with ~ 30ppm nearly uniform absorption.  We had it annealed. We have NOT been able to re-measure absorption (no chilled water).  We did not measure scatter before the annealing.  As a shot in the dark we are going to try re-annealing a well-known 1" sample.

Auxiliary Optics

From:   Michael Smith <smith@ligo.caltech.edu>

ADLIGO

Work under Project budget:

• IFO Layout: Mike revised the layout of the folded IFO by lowering the MC mirrors to the minimum height above the HAM table, with the MC plane being oriented in the local horizontal plane at LHO; and by lowering the signal recycling optics to their minimum level above the HAM table. The COC coordinates will be published shortly.

Work under Operations budget:

• ETM Telescope Suspension: Chris has a preliminary design for the magnetic eddy current damping structure for the ETM Telescope suspension.
• TCS: Aidan and Phil are analyzing the requirements imposed on the ETM telescope by the Hartmann sensor.

ELIGO

SLC:

• Ken has initiated manufacturing of the Eligo flat manifold baffle parts by CES and by outside vendors.
• The stainless disc (4) is scheduled to be finished 6-2-08 and delivered to CIT. The mounting brackets are scheduled to be finished by 6-5-08.
• The bevel on the edge of the ring support is scheduled to begin on 5-30-08; subsequently, the ring will be sent to an outside vendor and rolled to form, then returned to CIT for final machining. All parts for the flat baffle will be ready for oven oxidizing on 6-19-08.
• Luke expects to finish the drawings for the ETM baffle and the HAM5 baffle by 6-2-08. We are awaiting the scaterometer results by Steve Vass to determine if there are significant polishing striations in the surface of the polished stainless steel baffle mateial to cause a preferred orientation of the baffle material in the louver baffles. Ken and Luke are coordinating the baffle material source and fabrication vendors.
  
• Ken and Mike are in the process of estimating the magnitude of the expected vibrations of the manifold baffle. If the vibration amplitudes are deemed excessive, stiffening rings will be added to the inside diameter and the outside diameter of the baffle.  

Input Optics

From: David tanner@phys.ufl.edu

Adv LIGO Input Optics Development

• We are researching heater and insulator materials and geometries for DKDP segmented ring heater. (Luke)
• We are working on the mechanical design for the Mach-Zehnder modulator.  (Luke)
• Aanalysis of scattering and stray light in the IO optics is being carried out.(Rodica)

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For additional information about this report, contact Albert Lazzarini