Weekly Report for Week Ending February 28, 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

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LSC Issues (Reitze)

• Nothing significant from the LSC this week.

LIGO Laboratory Administration (Lindquist)

STATUS OF LSC MOUs (Lloyd)

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.

• GEO600, Louisiana State University, University of Massachusetts at Amherst and the University of Minnesota are being processed for signatures and will then be posted and submitted to the DCC.

FINANCIAL SYSTEMS (Funaro, Brambila, Oracion)

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

• For ACCOUNTS PAYABLE HISTORY Press Here.

>From: "Brambila, Ruth" <Ruth.Brambila@caltech.edu>

• No report

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

• Submitted three cost transfers to project accounting for approval and processing.
• Continued to work with IMSS to reconcile FY2007 carry forward amount to Oracle
• Created blank template for OPs monthly financial report for the month of February 2008.
• Started work with OSR and project accounting to determine total participant support committed on current LIGO coop agreement PHY-0107417.
• Met with monthly report revision task force to discuss enhancements/improvements to the monthly OPS report.
• 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>

• Three bids were received for the erosion control task at Livingston.

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

• The Tinsley contract is in the final stages of Caltech review before signature.  The kickoff meeting has been scheduled for Friday, March 7, at the Tinsley facility in Richmond, CA.
• Evaluation of video conferencing hardware and software is continuing.  The committee is now studying several options presented by Intercall utilizing Polycom equipment.  A demonstration of this equipment at Caltech and MIT is continuing with very positive results.  A presentation to the Executive Committee on the selected set of equipment is scheduled for March 31.

PROPOSALS and REPORTS (Lindquist)

This week we will be issuing requests for contributions for the monthly report to be sent to the NSF for the end of February.  The report is due to the NSF by Friday, March 14, 2008.

Quality/Safety (Tyler)

>From: Bill Tyler tyler@ligo.caltech.edu

• Nothing significant to report this week. Annual safety walk through of CIT labs taking place this week and next.

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

Summary of activities at LIGO Hanford Observatory (compiled by M. Landry)

• Large components of the HAM6 ISI were uncrated and found to be contaminated by meltwater. Stages 0 and 1, plus the stage 1 floor are being shipped back to Astropak for a phosphoric acid bath recleaning, then onto LLO for rebaking. We'll attempt to minimize impact on the schedule by front loading assembly, cleaning and buildups with parts in hand. Astropak estimates 4 days to turnaround the cleaning. Given reasonable times for shipping and the LLO bakeout, the parts are scheduled to return Mar 26.
• 4k IO alignments, for example, here, were studied in order to bring beams out the REFL and AS ports. First the simple Michelson, and then the PRM were locked. The goal is to have a set of alignments to use for the peek down the arms scheduled for Monday Mar 3.
• a rework of the REFL table was made - given the returned REFL beam no longer sees MMT1, two new optics were required to restore Gouy phase in the WFS3 and WFS4 paths, and work was done so that beamspots on ASC and REFL photodiodes were mostly unchanged
• the 2k is running smoothly in Astrowatch mode, with some acoustic tuning yielding small improvements in the noise at low frequencies, below 100Hz

Outreach (D. Ingram)

• Outreach visited the remaining three of six Central Washington University GEAR UP school sites in northern Washington between 2/20 and 2/22. The other three sites had hosted LIGO earlier in the month. On this trip, ~550 mid school students in Omak, Tonasket and Oroville sampled EOC Ingram's demonstrations on force, pressure and vacuum behavior.

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

No report received.

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)

• DR Locking: Continued problems with switching from single to double demod with just the DRM. Hopefully, the new RFAM monitor will shed light on this.
• Aux Beam Arm Locking: More RFAM. The fringe gotten from locking from the backside is very weak and can be totally swamped by a time varying RFAM. We now suspect the fiber of converting PM to AM. Next move will be to move the EOM to the ETM side of the fiber. There's also an analysis done by Lisa Barsotti (not on the Wiki !!) on this type of locking.
• Beam Dumps: We have measurements of BRDF from mirror polished steel and copper for making of a low scatter, high power dump. Key in getting low scatter with metals is to align the grain of the polish parallel to the incident beam direction. A preliminary mockup of the steel dump looks near as good as a black glass wedge (to the limits of our scatterometer setup). Plots to follow in the elog as soon as Steve gets back from skiing.
• GigE Cameras & Image Processing: We now have 1 CMOS and 1 CCD camera. We're putting them into a dedicated GigE backbone to test network capabilities as regards frame rate, resolution, etc. We are surveying vendors and will purchase from 1 more before getting back to software development (fitting, centroid tracking, diff detection, etc.). We are interested to see if network hardware will let us get rid of the analog MUX's and go to a completely GigE camera solution for the sites.

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Thermal Noise Interferometer (Black)

• This week we continued to work on what we started last week. Akira is working on improving the shot noise by rotating the polarization at the in-vacuo Pockels cell, and Greg is making progress on analyzing the ellipsometry data to extract dn/dT. Eric has been putting together orders for new optics, and Helena placed an order for the substrates for the doped-optimized coatings.

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LASTI (Mittleman)

BSC-ISI

• We have installed and tested damping loops on 6 degrees of freedom on stage 2 (hopefully we can get results posted on the Lasti ilog soon. We are now finishing up the MEDM/Simulink for stage one and should be able to start driving this weekend.

Noise Prototype

• Brett was in the BSC this week working on the controls prototype. He verified that the hysteresis exists in that suspension also. He is now reinstalling the OSEMs (which had to be removed to make the large angle tests) inorder to make small angle tests using the auto collimator.

LASTI Vacuum

• The septum plates have arrived and been moved into the highbay. We are in the process of testing the installation procurers and are hoping to do the installation next week.

Monolithic Development

• We have received the fiber strength tester and profiler from Glasgow this week. Russell is coming over next week to help Alastair install them. Alastair has been doing some welding test runs, with he will post his results in the Lasti ilog soon.

CIT Science Group (Weinstein)

_______________

Antony Searle:

• Attended Bursts face to face meeting at UMD.
• Presented http://www.ligo.caltech.edu/~acsearle/searle250208.pdf on Bayesian interpretation of some current bursts analysis practices.
• Visited and worked with Jonah Kanner and Doichin Denchev (a UMDundergraduate working on X-Pipeline).

_______________

Kent Blackburn for the Grid R&D group:

GRID APPLICATION DEVELOPMENT

• Wrote agenda of weekly LIGO-Pegasus telecon.
• Attended DASWG, CBC Code development, OSG-USERS and OSG-INTEGRATION telecons.
• Attended third ihope meeting with LIGO scientists.
• Troubleshooting TTU-ANTAEUS.
• Installed ihope software.
• Add -- nosubmit option to ldg_submit_dax.
• Studied ihope Python Code.
• Attempted to generate dag with ihope -FAIL (.ini file needs to fixed by LIGO scientist with ownership of file).
• Started making changes to ihope and other software to enable OSG dag creation with ihope by incorporating code changes into  ldg_submit_dax.
• Installed Linux OS as a dual boot option on laptop in preparation for trip to OSG All-Hands meeting and to Germany next week.

OSG INTEGRATION TESTBED

• Through discussions with VDT developers, learned of a package called STORK that can be used to replace the need for gsiftp, globus gatekeeper, and host certs on submit machines. Will need to discuss the ability of Pegausus to support this package as part of LIGO workflows.

OSG MANAGEMENT

• Attended OSG Executive committee telecon and reported on draft document on possible strategy for efficiently managing overly subscripted computing resources. The area of storage resources was also discussed. The was some agreement on the strategy but some committee members felt it needed to address other resource management issues. Further discussion will be needed before a revision to draft is made.
• Reviewed presentation materials addressing resource and project management of the OSG to be presented to the OSG Council next week.
• Attended OSG Area Coordinators telecon to discuss status of "troubleshooting", "engagement", "campus grids", "education and training", and "storage management".
• Received full set of letters of recommendation for candidate for the Grid Administrator position opening here at Caltech. Constructed a package of resume and letters and forwarded to staffing committee for review.
• Hosted Zhihui Du for two days here at Caltech. Prof Du is a leading researcher in high performance computing and grid computing at China's Tsinghua University. He is currently a visiting scholar at Georgia Tech. Through his collaborative efforts with Junwei Cao, also at Tsinghua, he has developed an interest in LIGO's grid computing challenges and the Open Science Grid. We discussed several areas for collaboration. Zhihui will be visiting MIT later this week.

_______________

Gregory Mendell:

• Nothing significant to report this week. I have been busy with system administration work and reviews, though I am spending a little bit of time discussing data analysis with grad students on astrowatch duty at LHO.

_______________

Pinkesh Patel:

• Wrapping up implementation of Resampling in the lalapps code.
• Taking some Astrowatch shifts.
• Reading up on SEI installation docs.

_______________

Amber L. Stuver:

LIGO Research

• Presented a few results (regarding the PSDs of the factors used in the generation of h(f) and h(t)) at an h(t)/calibration telecon and started expanding the initial investigation from comparing the one second factors to looking at the 60 second factors.  I expect to have results for this early next week.

SEC Work

• Gave control room tours to ~125 students.
• Presented the public tour to a group of ~25 senior citizens.efficacy of teacher professional development workshops.

_______________

Diego Fazi:

• Running a bank simulation to test the efficiency of the PTF template b.
• Working on the implementation of a distance for the PTF intrinsic parameter space.

_______________

Anand Sengupta:

• Finished review of trigScan codebase - some action items followed up.
• h(t) calibration telecon - working with Keita et all to understand what work has been done in the past regarding CBC hardware injections.
• Finshed another set of EOB injections using band-pass templates.

_______________

Kipp Cannon:

• SGR flare review work.
• Completed excess power galactic core pipeline and upper limit script.
• Began re-running S4 string search in preparation for paper/code review.
• Attended burst f2f by phone.

_______________

Drew Keppel:

• Working on calculating the false alarm rate for the S5 1Yr Low Mass CBC Search to be used as a loudest event statistic.
• Following up nearby missed software injections in EOB and SpinTaylor injection runs.
• Work associated with the review of the S5 1Yr Low Mass CBC Search.

Laboratory Computing (Anderson)

LDAS Software Systems (Maros)

• In the past week the use of valgrand has been instrumental in locating and fixing several race conditions in the diskcacheAPI. These changes are going to be installed on ldas-dev for multi-day testing.
• The cntmonAPI's test report tool has been modified to eliminated duplicate and triplicate usage report messages.
• The manager has been modified to use two variables to control the time allowed for an API to start.
• System testing was done using version 1.9.206 of LDAS. The dbperformance test continues to core dump when run from SystemTest.tcl. The week long testing on ldas-test used version 1.9.210 of LDAS. The only errors were from the datacondAPI reporting no such symbol.
• Work continues on integrating the datasock test into SystemTest format. Most of the work has been in merging the multiple script files previously used for this test into just two scripts.

LDAS System Administration (Anderson)

Caltech

(Dan Kozak)

• More 6140 benchmarking.
• Unstuck archiving for /home1 at CIT.
• Got A5 RDS data archiving to tape at CIT.
• Set up ldas-sunbox2/ldas-suntest2 to access /data/nodeX for Ed Maros' testing.
• Gave Larry Wallace some Solaris install on thumper advice.
• Fixed archiver.cmd at LHO so that the tape space monitor would work again.
• Did some work with the arrival of new Sun equipment, but handed off a lot of it due to illness.
• Set up testing situation for Scott Koranda with a bunch of files that will block forever rather than stage from tape.
• Did a little work with an LDRTransfer problem (cut short by illness).

(Phil Ehrens)

• One possible new fan failure occurred this week.  The fan was vibrating at fairly low amplitude, but was inducing ~ 20 correctable HD errors per day on the nearest drive. Within 12 hours after the fan was replaced, the drive stopped generating errors.
• 5 MCE errors, each on a seperate node, have been logged this week after more than 2 weeks with no errors at all.
• Discovered an intermittent problem with the second NIC on ldasbox2. This NIC sometimes drops out entirely for hours at a time, and spontaneously comes back online. I found a PCI NIC to replace it with, but haven't installed it yet.
• Documented NIS+ configuration for CentOS desktops in the wiki.  There may be an issue with the CentOS XScreensaver configuration and NIS+ authentication or user home automounting as done here.
• The desktop machine Kitalpha has been upgraded to CentOS 5.1. I also installed a dvd burner and an additional Gb of memory. Kitalpha is a 3.4GHz system with a fast memory bus, and it now has 2Gb of ram. The version of xorg shipped with CentOS was able to sync a monitor at 1900x1200 using the GPU on the motherboard, which is good news indeed.
• Ongoing work on the 2008-2009 MOu review website.  I have not been able to retire the 2007-2008 website yet because some groups are still updating their documents, but I have made good progress modularizing the cgi scripts that the site runs on.

MIT

(Fred Donovan)

• Remaining power issues from outage: some surge protectors bad, new ones ordered. two circuits blown, reset by electrician (some rewiring done).

Hanford

(Greg Mendell)

• I fixed a few minor problems with the archiving of raw conlog "Up" astrowatch data and implemented automated "Gap Checker" monitoring of this data.  I have verified that all of the raw conlog "Up" astrowatch data produced so far at LHO has been archived and successfully transfered to Caltech.  Gap Checker will send emails to the relevant LDAS system administrators if further problems occur, and I will continue to make routine checks by hand on a regular basis.

General Computing (Wallace)

MIT

(Fred)

• Set up opteron server for burst group (2 cpu dual core opteron).
• Set up new laptop (fedora/vista).
• Ordered new pc - solidworks 3GH.
• Updated ligo (solaris updates) and did solaris 10 live update - will boot into new os this w/e.
• Booted tubera into solaris 10, stable. using ilog web mgt. interface for mit ilog -- seems ok.

Livingston

(Dwayne)

• Minor adjustments to the front gate.
• Power cycled some kantech controllers at the Y-end to un-stick some relays and allow proper operation of the laser hazard light.
• Applied a few more of the recommended changes to the ICS.
• Finished pulling new fiber bundle from patch panel in Staging building comm. closet to patch panel in LDAS room.
• Tested PolyCom PVX software, installed under XP on Parallels on a Mac. All went well.
• Received and installed a new plotter.
• Booked a trip to CIT for LSC meeting setup.
• Moved more PCs to the new network.
• Other usual/unusual user support requests.
• Cleared spam trap.

Hanford

(Christine by Larry)

• Tracked down a server problem. The raid system for the home accounts failed. The unit was replaced with the backup unit and the broken unit has been called in for repairs.
• Tracked down a network issue. Power cycling of the router resolved the problem.

(Larry)

• Assisted a couple of users resolve some configuration and e-mail issues.
• Assisted Christine and Dave on tracking down some h/w problems going on at the Observatory.
• Working on a interim backup system until the new one is installed and the disk backup system is repaired.

Caltech

(Christian)

• Cleveland Mak - Multiple IE explorer pop-ups. Cleveland’s computer was infected with multiple spyware. I created a full backup his computer and rebuild it.
• Cindy Akutagawa - Inbox in Eudora was quarantine. I removed spyware html emails in Eudora.
• Eric Gustafson ­ Installed MS Visio 2003 on Eric’s laptop.
• Continued testing Polycom conference system this week.
• Other misc.: Continued onsite software/phone support.

(Veronica)

• LSC:  Ongoing web support of the March meeting.  Added another query for comprehensive payment/registration information per a request from Dorothy. Took part in test/troubleshoot of the videoconferencing options. Continued work on the website redo.  Updates of the database of technical papers.
• LIGO:  A downloadadble video of Einstein's Messengers per Albert's request.  High-res images for NSF and others.  Web updates /user support.
• CaJAGWR:  Taped /processed the 02/26 talk.  Website updates /user support.

(Melody)

• New DCC: Continuing with DocDB installation and configuration on the new DCC server.
• LAAC: Continuing testing of the wiki  (includes checking the differences between starting the mysql server through mysqld_safe and libexec/mysqld).

(Mike)

• Worked on setting up an X4500 and started to load Solaris. Larry finished this up.
• Loaded a NISPLUS Linux workstation for John Miller.
• Worked with Christian on some spyware/adware issues for a few users.
• More testing with the Polycom and EVO per video conferencing.
• Trouble shot a SUN workstation that turned out to be a corrupted kernel. I’m rebuilding this box now.
• Other misc. sysadmin work for CIT & LHO.

(Larry)

• Placed a few orders. Purchased a number of computer support items and distributed them. Working on orders for s/w licensing. Multiple items for the LSC-Virgo meeting coming up. New PC's for a couple of people and the loaner pool.
• Installed a new UPS in one of the racks. The old unit just quit working and had to be replaced. It caused some minor problems but nothing major and things did recover without too much difficulty.
• Time spend working on the Polycom setup and seeing how well it will work with different systems. A lot of testing has been done between the four LIGO locations. Working with David S. and Ed J. on multiple fronts concerning the product and evaluation.
• Worked on a couple of different computer setups. Worked with Mike on troubleshooting a couple of systems he was setting up.
• A lot of time spent getting information to help in the setup of the L-V meeting. There are still a lot of logistical issues to be worked out.
• Regular user assistance.

Advanced LIGO and Supporting R&D (Shoemaker)

Advanced LIGO Systems

Modeling and Simulation

From: Hiroaki Yamamoto hiro@ligo.caltech.edu

Static IFO Simulation (Hiro, John)

• Hiro is redoing the calculation of the wedge effect for the stable and marginally stable cavity configurations.
• At Florida, the calculation was done with a low accuracy to get answers during the workshop. Now with higher accuracy and see if there is any side effect.
• The contrast defect due to the wedge angle may be worth for AdvLIGO than initial LIGO with the same wedge angle.
• When fields have curvatures R1 and R2, the mode mismatch is

(1/R1 - 1/R2) k w^2 = k dR / R^2 w^2. 

When dR = eps * R, this mixing is

k eps / R * w^2

R(advLIGO) = 0.2 * R(initLIGO) and w(advLIGO) = 2*w(initLIGO)

So this mismatch factor can be more than 10 times larger for the advLIGO than initLIGO case. More quantitative study will be done.

Time Domain Simulation (Hiro, Lisa, John)

• Lisa is working to implement SPI in her locking simulation using e2e.
• e2e did not work as is when there are more than one laser sources injected from different ports, here from the main laser to RM and two additional laser to ETMs.
• Hiro is working to fix it, or trying to find other workaround.
• During this work, a bug was found for FUNC_X with vector outputs. A new version of e2e will be released with the modification needed for Lisa.
• John is working to implement a better PSD primitive.

Mechanical Simulation for advanced LIGO (Hiro, Sany and SLU team)

• Sany's group is working to implement the active seismic isolation system in the e2e framework, based on the state space model provided by Brian.
• Last piece missing was the low frequency region correction handled by the FIR filter, placed between the ground motion and ISI.
• Noticed that the FIR filter (to simulate the HEPI) based on e2e showed different characteristics from the equivalent result based on Matlab. Hiro found a typo in an included file that I had revised. Correcting the typo fixed the problem. After this fix, added DDC (Digital-Digital-Converter) primitive in between the input ground motion and the FIR filter so that e2e computation time could be different from the time step used to obtain the filter coefficients (4.88e-4 s). Confirmed that the filtering characteristics with computation time steps of 1.33e-5 s (e2e’s standard time step) and 4.88e-4 s are the same.  

Facilities Modifications and Preparations

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

• No report this week.  

Prestabilized Laser

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

• No report this week.

Interferometer Sensing and Control

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

• The ISC team is finishing up DRR-CDR documentation: design requirements and conceptual design. These are posted on the AdLIGO wiki (and of course have been submitted to the dcc). We have also been looking more into the idea of locking the arms by injecting a probe beam from the ends of the arms. This looks most feasible if we use a significantly different wavelength than 1064 nm, and so we are looking into the reflectivity of the TM coatings over a wide wavelength range. Other ISC efforts are of course being put into the eLIGO OMC/DC readout preparations.

Control and Data Systems

From: Rolf Bork rolf@ligo.caltech.edu

• No report this week.

Seismic Isolation

From: Ken Mason kmason@ligo.mit.edu

LLO HAM SEI ASSEMBLY

• We are planning on installing the ISI in HAM6 next week. We should get the doors off Monday so that we can start erecting the installation fixture.  Here's a tentative schedule:
  • Remove HAM doors, begin assembly of installation fixture  -Mon. March 3
  • Finish assembly of installation fixture  -Tues. March 4
  • Remove the ISI from the test stand, remove the risers and install them with the brackets inside HAM6. This step is something of an unknown in terms of how difficult it is or how long it will take. I'm anticipating that it takes most of the day. -Wed. March 5: Install ISI in HAM6. The objective is to get it securely on the support tubes. Cabling to the breakthroughs etc. is a lower priority and does not have to occur at the same time. -Thursday March 6
• We intend to continue testing the ISI during the early part of the week, while the installation fixture work is going on. - Brian O.

LHO HAM SEI ASSEMBLY

• Have most hardware in hand to complete the riser installation on HAM6 Support Tubes.  Continue staging and organizing clean room space and parts  & tooling cleaning for HAM6 ISI assembly.
• Found large plate parts of HAM6 ISI assembly: Stage0 Base, Stage1 Base, and Optical Table, to have gotten wet in their Crate while stored outside at LHO.  Parts were outside for about two weeks and got snowed on while principal SEI personnel were on travel.  The parts were not well sealed in the crate but should not have remained outside for that length of time. Rod Luna has scheduled the plates to be picked up Friday morning for a Monday morning delivery to Astropak to be recleaned.- Hugh R.

SEI ELECTRONICS ASSEMBLY AND FABRICATION

• All electronics for both sites has been completed.  The  coil drivers are being tested this week, and will be ready to ship next week.  The field cables for Hanford are somewhere at LLO.  Brian O. is trying to locate their box.  I'm in very preliminary stages of exploring the redesign of the Capacitive Position Sensor Field Interface box.- Ben A.

Adv LIGO HEPI

• Received a quote from Parker for the control valves. Also visited a fabrication shop interested in supplying the actuator and a plumbing contractor that does work in the Washington area.- Ken M.

Suspensions

From: "Greenhalgh, RJS \(Justin\)" <J.Greenhalgh@rl.ac.uk>

ALUK held its latest Project Management Committee on 22 Feb 2008 (See LIGO-M080027-00-K). A brief activity summary follows:

• RAL: All parts for the BS prototype are out for manufacture. OJEU process status remains as follows:
• Machined items. RFQs sent out with return date of 5th March
• Weldments. Responses to RFQs returned.
• Blade springs alternate material suppliers being investigated

Work on investigation of alignment problems is taking priority.

• Glasgow: The prisms have been successfully bonded to the penultimate and reaction masses. The ribbon pulling machine is substantially complete at LASTI. Characterization parts shipped. Work in hand on welding machine.
• Birmingham/Strathclyde: OSEM manufacturing FRR scheduled for 29th Feb. Feedback on the electronics has been delayed and a new list of required dates for this information is being produced. The ESD has been shipped. The sensor part of the violin-mode sensor has been prototyped and tested.
• Overall: Work on ribbon/fibre machines and bonding, work on OSEMs, and work on electronics is going well albeit with some delays. Excellent news from LASTI on the mechanical ETM/ITM structures, but a frustrating difficulty has cropped up in aligning the suspension. With considerable help from our colleagues in US we are working hard to understand the cause and implement a solution.

We note that the SPI interface is still undefined, and that it may require rework of parts to accommodate it.

From Janeen Romie and Norna Robertson

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

HAM Suspensions for Advanced & Enhanced LIGO

• Output Mode Cleaner Suspension: The osems were  re-installed and aligned in the OMC suspension after Sam left on Friday, with the metal bench suspended, so that Tobin was able to take transfer functions and test damping. Transfer functions compared well with previous one taken at Caltech (minor differences due to slightly changed parameters). Derek is working on the Solidworks layout of the HAM 6 optical table with respect to positioning of the OMC suspension/bench and counterweights for Sam. Hazard analysis is out for signatures. Installation plan is being updated.
• Recycling Mirror Suspension: Mike Gerfen gave us the stainless structure weld test sample and we've made some changes to the structure design due to the warped sample. We've agreed to thinner gussets to reduce warpage and reduce risk of welding quality degradation with the assumption that this will reduce first mode by small percentage. We have received quotes for the blades and are reviewing them now. Calum & Greer changed the blade platform design after their finite element analyses (Greer with Cosmos and Calum with ANSYS) pointed out areas that needed a bit of stiffening. Both Bob & Greer are working on additional detail drawings.
• Input Mode Cleaner Suspension: Mike Meyer has performed preliminary finite element analysis of the aluminum IMC structure alone and with the baffles Luke Williams designed for 2 sides. The first mode goes from 57 Hz to 70 Hz.

BSC Suspensions for Advanced LIGO

• Refer to Justin Greenhalgh's monthly report.
• Additional details
  
  Electronics: the schedule for delivery of reports to Birmingham from LIGO on the quad electronics units was discussed. A mature draft of the top mass electronics report has already been sent. Jay is aiming to get reports on the UIM and PUM boxes to Birmingham by ~March 7th. Work on the satellite box testing will follow after that. Visit to LASTI to install the boxes is likely to take place the week beginning 7th April.

Core Optics

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

• Astigmatism caused by the wedge in the Beamsplitter is being studied, namely the effect on sidebands, and the effect on the balance of power stored in the arms.
• The steering mirror from LLO still measures a large absorption after cleaning, and also trying to measure the absorption from the back (to avoid surface contamination).
  A theory about absorption degradation due to UV exposure is being explored.
• We will be sending an Aluminum Oxide ~80mm cube to UWA for scatter characterization.
• The 250mm m-axis piece is still in Japan.
• Still working on the COC PDR
  
  • http://ilog.ligo-wa.caltech.edu:7285/advligo/COC_Preliminary_Design_Review  
  • committee and COC team telecon on or about 2/21 - Still in progress
  • committee report issued on or about 2/28
• Tinsley pathfinder kickoff meeting is scheduled for 3-7-08.
• A concept sketch for Riccardo re. thermal issue with test mass. (Ken Mailand)

Auxiliary Optics

From: Michael Smith smith@ligo.caltech.edu

• IFO LAYOUT: Mike has completed documenting the new locations of the IFO mirrors for the folded stable recycling cavity. It was necessary to place the PR3 and SR2 mirror suspensions directly on the surface of the HAM tables and to steer the beams down from the ITM height. An approximately 100 mm spacer must be placed under the BS suspension. The stay-clear distance between the BSHR3 and BSAR3 ghost beams and the main IFO beam in the power recycling cavity is approximately 40 mm, with the 0.8 deg BS wedge. Peter Fritschel believes that this distance could be reduced to 20 mm, allowing the BS wedge to be reduced further if necessary.
• SLC: Ken will be receiving samples of enameling steel, which will be porcelainized. The intent is to evaluate the optical properties and the vacuum properties of porcelainizing on enameling steel, low-carbon cold rolled steel, and prepared stainless steel--these are the three choices of base material. Ken is completing the preliminary design of the ELIGO manifold baffle, which will be assembled using hardware, without any welded joints.
• IFO PROBE BEAM: A probe beam @ 0.532 nm could be launched from the ETM direction and it would pass through the SM3 and SM2 mirrors and then deviate before hitting the SM1 mirror at a convenient location on the HAM table to enable acquiring the probe beam.
• TCS: Ken made a conceptual drawing in SW based on Riccardo's idea for radiatively cooling of the ITM HR surface with a cold surface. The cooling  apparatus must be located between the ITMHR and the arm cavity baffle.

Input Optics

From: David tanner@phys.ufl.edu

• We are working on the  Adv. LIGO layout, based on stable recycling cavities and the latest changes to various pickoff beams. (Luke)
• ZEMAX has been installed at UF and we are learning how to use it. (Rodcia)

eLIGO IO

• Installation activities continue at LHO. We are working on the new layout of wavefront sensor (WFS) 3 and 4. The change of reflection port position from between the SM and MMT1 to between MMT2-MMT3 has changed the beam sizes and Gouy phase significantly. We are redesigning the wavefront sensors to restore the beam sizes and the Gouy phases. (Muzammil)
• We also are working on other aspects of IO beam alignment at LHO, including adding the new cameras. (Kate)
• We are trying to estimate the costs of having UF manufacturing the cans that hold the cameras at the viewports, including materials, time, and anodization. (Luke and David)

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