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The LIGO Executive Committee Agenda for Monday September 24, 2001 will be:
(Meeting time: 10:30 am Pacific Time)
Open meeting 10:30 - 11:30
Special Items:
No report.
WBS 1.2 LIGO Operations--Administration
Weekly Site Telecon not held this week due to
SUS Conceptual Design Review for Advanced LIGO and key personnel on travel.
The list of current actions revised to reflect
the status of open actions assigned through September 13, 2001 may be found
at ACTION
LIST.
From: Ed Chargois <chargois_e@ligo.caltech.edu>
>From: Cleveland Mak <mak_c@ligo.caltech.edu>
Web pages for the DCC give simple how-to's for document numbering, easy access to the latest on-line documents, and search capabilities for the DCC database. Take a look. . .
ACCOMPLISHMENTS
| Packages | Faxes | |
| In | 39 | 39 |
| Out | 9 | 35 |
Press here to access the DOCUMENT CONTROL CENTER WEB PAGE.
From: Esther Cunningham <esther@ligo.caltech.edu>
Press here for ACCOUNTS PAYABLE HISTORY DATA.
From: "Brambila, Ruth" <Ruth.Brambila@caltech.edu>
From: irena@ligo.caltech.edu (Irena Petrac)
SUPPORT (Wood)
Dorothy Lloyd
Progress Period from 09.14 to 09.20
Accomplishments:
WBS 1.4.1.2 Project Controls (LIGO Construction)
The end-of-August Quarterly Progress Report will be due at the end of September, and I have requested contributions by September 21. This could be the last Quarterly Progress Report required under this Cooperative Agreement, although we will still have to provide some kind of Annual or Final Report. Under the new Cooperative Agreement, we think that only an Annual Report will be required.
The following Change Requests have
been submitted.
| CR-010006 | WBS 1.1.4 (OPS) | Roof Shelter for Concrete Pad Adjacent to Erosion Control Pond (Livingston) | M. Coles |
| CR-010007 | WBS 1.2.4 | Core Optics Components, Repolish/Recoat Beamsplitter | S. Whitcomb |
| CR-010008 | WBS 1.1.4 | Five-Ton Crane for the Staging Building in Hanford | O. Matherny |
| CR-010009 | WBS 1.4.2 (OPS) | Additional 10-W Laser for PSL Lab | S. Whitcomb |
| CR-010010 | Advanced R&D | Seismic Isolation System PD ETF Mechanical Contract (APPROVED) | D. Coyne/ G. Stapfer |
We scheduled a meeting of the LIGO Change Control Board for Tuesday, September 11, 2001, at 9:00 am PDT. An agenda was distributed electronically (LIGO-M010244-00-P). This meeting was postponed in light of national events and will be rescheduled.
Press for the latest Contingency
Needs Projection.
From: Kris Duncan <kris@ligo.caltech.edu>
From: Ed Jasnow <jasnow@ligo.caltech.edu>
No report this week.
On Sep 17, Mark Coles, Steve Maguire (SLU) and Warren Buck (UW) met at the NSF offices in Arlington, VA with Tim Olson (SKC) on conference phone. Vic Cook had arranged the meeting between us and personnel in the NSF education directorate to try to help us get the ball rolling on efforts to increase the pipeline for african-american and native-american students into the physical sciences as part of LIGO outreach.
LDAS: Called cybernetics about the maintenance contract on the
tape library. Will be purchasing the contract which requires shipping the
library to cybernetics for inspection. Received the shipping box today
so the unit should be going out tomorrow to cybernetics. Rebuilding admin
here to allow for the disk to disk backups of various machines. I have
a couple of finishing touches to do on this, but it is 95 percent complete.
Admin will be back up at around 3:00 CT today.
GC: installed some free security software on our windows 2000
server here in LA to block all of the attempted infections of nimda. We
applied all of the patches to this box previous to the virus/worm outbreak
this week, but just to be safe, I have blocked all connections on port
80.
CDS: Nothing to report (Shannon Roddy)
Detector: Optics and Installation: Installation of the door hardware for the Laser Safety Interlock system continues, as well as additional exterior security cameras at both ends. Visited a Jefferson Parish Sewerage & Water Board pumping station with Mark and Szabi to inspect an acoustical enclosure that had been installed by a potential supplier of panels for the PSL. We made measurements of the effectiveness of the enclosure to isolate over the frequency region relative to the frequency noise induced by the laser table. (Jonathan Kern)
Other: High school physics students from Istrouma High School in Baton Rouge visited LLO today with their teacher - Wilson Doucette. They would like to replicate the SST program begun at LHO. Wilson participated in our pilot IRET program at LLO this summer. He has independent funding from Dow Chemical to support this activity and has gotten in contact with the High School teacher in Portland to get some pointers regarding the program with LHO.
| Installation&
Commissioning:
Livingston |
Other Science/EngineeringActivities:
Issues/Concerns |
See also the Installation web page
Attempts to lock the X arm cavity met with less success. The arm was well aligned, and we had flashes of light on the transmission monitor QPD, but the fringes seemed to be going through too fast. The problem may be the frequency noise from the modecleaner. This initiated an effort to level the modecleaner.
A first cut was made at commissioning the WFS for the 4 km modecleaner. The first step in this process, identifying the bounce mode frequencies of the different small optics, immediately lead to a puzzle. There was only one peak near the expected frequency (16.25 Hz), which was identified as MC1. Eventually the missing peaks from MC2, MC3, MMT1, MMT2 ans SM1 were found, but near 19.25 Hz! Finally the mystery was resolved when a mostly used spool of molybdenum wire of the correct diameter was found in the optics lab. The higher elastic modulus of Mo pretty well matches the higher bounce frequency. We are still contemplating what, if anything, to do.
The Q of the longitudinal, pitch and yaw motions of the mode cleaner and mode matching telescope masses were measured. All now show simple decay curves with Q between 1000 to 6000 depending on the motion and the amount of recoil loss.
There has been improvement in the frequency stabilization loops. By changing compensation, the fast servo loop unity gain frequency has been increased to 1/2 MHz. The frequency noise spectrum is now dominated by acoustic excitation and the excitation of the vibrational modes of the periscope on the laser table. The acoustic isolation of the laser enclosure and the change in the persicope beam have become pacing items.
Whilst the modifications to the frequency servo were contemplated, the spare frequency servo card was examined. There were a few small differences due to the revision level and a number of components were not present on the board.
We are also wiring in a number of PSL signals to the DAQ system. We will be using them as an aid in the resolution of our new intensity issue.
Sander Liu
Fabrication and test of modules for the digital suspension upgrade is complete with the exception of the Anti-Image boards. We are waiting for the final delivery of filters from Frequency Devices. They are due by 9/20. We currently have enough Anti-Image boards to complete the first IFO.
Sander Liu
Received 50 each of the 44 pin Positronic Connector for the antialiasing
filter chassis. This will help us complete building four LEMO chassis for
delivery. Three other boards are still waiting for the four pin LEMO connectors
with a mid October delivery date.
I will continue on the front end code. Now that I have the I/O connected and tested, I need to test the filtering algorithms and verify everything in the middle is operational. If I can get this going tomorrow, then we should be ready for next week.
Send the numeric entry widget which was developped for DTT to the ROOT development team for incorporation into the standard ROOT release.
Our PSL enclosure wiring still doesn't work; opening the doors does not set off the alarm or trip the laser. We have verified that the kill switches DO trip off the laser. Ben had the Caltech electricians in, and after 2 days, they couldn't fix it. Ben has a new, much simpler, wiring diagram, and will re-wire the whole thing himself (so that it's done right).
We went over different issues with Peter. He advocates holding off on changing the layout of the PSL until the dust settles, some months from now.
Facilities (Vass, Jones, Smith, AJW):
CES is still constructing custom support legs for the last 3 optical
tables. Larry awaits the shims that are required to bring all the
tables up to their desired nominal height.
We expected the new 5'x12' optical table last week, but it turns out that it was never ordered, because the single source justification was not sufficient. Apparently, they need written quotes from at least 3 vendors, no matter what (and they never told us). So, we wait another 6 weeks...
We now have several options for in-vacuum cables: Cooner wire can make 25-conductor, twisted pair, braided shield cables with FEP teflon insulation on each conductor; either 5 mil or 3.5 mil. MDC can do the same, with 2 layers of kapton insulation on each conductor; it will be stiffer than the Cooner wire but less stiff than the MDC wire we have now. We also could ask Santa Fe Textiles to do the twisting and braided shield.
Larry still awaits samples of braided in-vacuum wire for testing; Santa Fe Textiles is 2 weeks late on this. We hope to have samples of the twisted, braided Cooner wire, for testing on our small MCCM seismic stack.
Dennis and Steve has assembled our small MCCM seismic stack on an optical table, and are measuring transfer functions using natural ground motion and our Wilcoxon 731A accelerometers. AJW prepared a simple 1-dim (vertical) model of the stack transfer function, and estimated mirror displacement psd. Results of the transfer function measurements are ambiguous: only getting good readings from 1 to 70 Hz, around the resonant peaks; and there is some evidence that 2 of the 3 stages are shorted.... We just got back our shaker, so will do swept sine measurements with it in the hope of getting to lower and higher frequencies.
Steve has ordered 9 new optical quality viewports with AR coating, and is shipping out 12 lower-quality existing viewports for AR coating, all from Cascade Optical. Larry is designing new viewport seal flanges which will hold the window at a 2.5degree tilt, to minimize backscatter into the IFO. He's done the drawings and already has CES building them (5 are needed). Mike Smith has done detailed BRDF calculations of the backscattering, and concludes that 2.5degrees is sufficient, even for the ETM transmitted beams (which are the worst case).
Steve and Dennis vented the 40m last week to pull off 2 viewports for re-coating, and added another CC gauge at the same time. Venting and pump-down proceeded well.
Suspension controllers (Ben Abbott, Heefner):
Ben continues to work on the detailed Protel drawings for our 10 digital
suspension controllers. We hope to have a mini-review of these, in
a couple of weeks. Estimate that if they are approved in October,
they could be ready for assembly and commissioning in January.
Suspensions (Romie):
Submitted drawings to CES for fabrication of 5 test mass suspensions.
Included in the package are drawings for magnet fixtures. KineOptics is
designing and fabricating the guide rod fixture for these optics.
CES is also reworking the sensor/actuator plates for the small optic suspensions
to allow more room for the beam. They are currently working on the magnet
fixture for those optics.
Core optics (Billingsley):
Gari received a quote for core optics polishing from CSIRO, and
is awaiting a quote from WavePrecision. She is also preparing coating
specs for the core optics. AJW prepared transmission values and estimated
tolerances.
Scattered Light control (Smith):
An estimate of the scattering of the ETM transmission beam from the
output window indicates that a tilt of 2.5 degrees of the window is adequate
to reduce the scattering to an acceptable level. Larry Jones has designed
a flange holder to tilt the output window at 2.5 deg (see above). The
scattered light phase noise calculations are being reviewed to check
the parameters used for the 40m IFO, and to incorporate the effect of the
signal recycling mirror.
Computing (Bogue, Ugolini, Bork):
Lisa has mounted the martian network shared disk onto our gateway (rana),
read-only. She has rana samba-serving the GC disk /home/cit40m onto
the PCs on the martian network. We now have well-defined pathways
to get code, data, etc., to and from the martian network without compromising
security. Rolf expects to complete the population of the martian
network shared disk, when he returns after next week.
We have also placed a Faraday isolator between the in-vacuo Pockels cells and the beamsplitter. When we locked both arm cavities simultaneously several weeks ago, we noticed significant coupling between the two cavities, and we suspected this coupling to be of optical origin. Inserting a Faraday isolator was not deemed practical at the time because it would have required significant realignment of the optics. The new optics will have to be aligned after they are installed, and we are taking advantage of this opportunity to install an isolator.
Rapid test of the proposed adLIGO hydraulic pre-isolators on a BSC equipped with LIGO I seismic isolation has been elevated to top priority. This is a response to the excessive impulsive disturbances now routinely observed at LLO. Previously LASTI had not intended to install anything in BSC0 until the adLIGO stack/suspension prototypes were ready next year, so this represents a major perturbation.
LLO has shipped back to MIT the spare downtube and BSC leg element set (thanks Gary, Harry and Ed C.!). Despite its many travels and months of outdoor storage, the barrier seals appear intact and recleaning/rebaking should not be required. We are tracking down other spare BSC stack parts throughout the project with the aim to get a stack installed by second week of November.
In the meantime we have accelerated the grouting under the support piers. Joe Giaime and Brian Lantz have asked us to study the reaction impedance of the piers by temporarily removing the load and measuring their free eigenfrequencies. This information is needed to inform the hydraulic isolator controller design. The test will commence as soon as the grout reaches full strength (about 1 week after pouring).
Hydraulic pre-isolator design and test (Mason, Phinney)
Springs have been designed for two design scenarios. The first design uses 2 springs per leg with a vertical stiffness of 1 x 10^6 n/m at 8 Hz. The other approach uses 4 springs per leg with a vertical stiffness of 1.5 x 10^6 n/m at 8 Hz. Design sketches for each of these approaches are being created so that a decision by the advanced seismic group can be made on the right approach to pursue.
Pumps, valves, accumulators, and drums of hydraulic fluid are coming in (also a substantial "spill containment pallet" which Stanford tells us is a very good idea). Joshua is assembling a test stand in the machine shop to evaluate dynamics and noise issues in the proposed actuators. One key variable is how the performance will be affected by placing the drive pumps and reservoirs remotely in the Observatory mechanical rooms.
LASTI Test Cavity Suspensions (Weaver, MacInnis, Miller, Ottaway)
Betsy Weaver visited us for a week and helped us learn how to suspend and balance the SOS, as well as getting our cleaning and handling infrastructure in shape. We now have both cavity optics plus a spare ready to go, working OSEMs and working SOS controllers with EPICS support.
We had tentatively scheduled an incursion into HAM13 to install these in vacuum for week of 9/24; due to the new activity associated with the hydraulic pre-isolators, we have now put this installation on hold until some smoke clears.
LASTI PSL (Ottaway, Rollins)
We are expecting delivery of our repaird MOPA from Lightwave sometime next week. Meanwhile using our NPRO we have started to exercise the electronics and optics together. Working around two bad boards, a miswire in the crossconnect and a cold solder joint in a detector head, we finally got a good error signal off the pre-modecleaner reflection last night. Plan is to have the PMC locking on the NPRO beam this weekend and then push on to the frequency servo next week.
LASTI DAQ/GDS/CDS computing (Mike)
Daniel Sigg and John Zweizig took advantage of their attendance at the MDC a couple weeks ago to install GDS and DTT software and give us some advice about how to configure our network. Unfortunately we had another RAID disk failure (there is a bad batch affecting all LIGO sites) so we did not get as far as wanted. However we did get together a plan for improving the network architecture so that, for example, our GDS system can simultaneously support local LASTI and observatory data reduction and diagnostic tasks. We will need to procure additional hardware for this which is not currently budgeted.
A failed router on our CDS subnet knocked us out for a day, interfering with Betsy and Dave's efforts to balance the SOS; Ed Daw, who happened to stay on after the MDC (given no choice, there being no flights last week!) was able to debug and fix the problem for us.
LASTI Infrastructure (Mason, MacInnis, Miller)
A mezzanine for staging the BSC stack in LASTI has been designed and is out for quote.
Cable trays for LASTI have been quoted; an order will be placed today. We are planning to do installation in-house so we can phase it in gradually as the electronics are added. This will help keep the trays out of the way for the SEI installation.
Construction of the custom psl enclosure has begun at the outside fabricator's shop. Several issues with the suppliers drawings still remain to be ironed out.
Environmental Issues (Zucker)
We are experiencing severe shaking from pile driving and contamination from trucks at the nearby construction site. After a lot of running around I woke a sleeping dragon in the form of MIT's real estate director, who has now threatened to revoke the developers' lease (MIT owns the land) unless the contractors shape up.
Simulation and Modeling (Bhawal)
Weekly E2E Physics MeetingLIGO Data Analysis SystemBiplab discussed mode mismatch calculations for LIGO using time domain modal model in E2E. After that Bill Butler talked about measurements of seismic correlation among stack locations at Hanford. This work was done by Bill and Robert Schofield. The data will be used in Han2k model for obtaining proper seismic noise spectrum.
Modal model calculations
(Hiro) Time domain modal model has been revisited to clarify various uncertainties in calculating various mode decomposition matrices. Also two null tests have been analytically demonstrated to understand how a modal model with finite number of modes work. The LIGO Note T990081 including these works has been updated.
(Biplab) Comparison with an analytical derivation verified that the direction in which the maximum power points lie in a beam reflected from a tilted mirror is correct in e2e simulation. Also tested: simulations of the beam-shifter module and cavity with lateral shift in mirror (each separately and also when a beam-shifter's output beam is introduced in a cavity with same shift in mirror: a null test).
Alfi
(Ed Maros) Worked on Makefiles for new JAlfi
(Bruce) Currently working on finishing the Alfi5 file parser.
(Melody) Continued on the implementation of the graphics portion of alfi5. Working on drawing the primitive nodes and ports.
Software Systems (Blackburn)The Parasoft software diagnostic tools, Insure++ and CodeWizard have been installed on a linux and solaris workstation. The LDAS configuration scripts will be modified to detect these and compile with the option to use them to build versions of LDAS that can be processed for coding inconsistencies and errors using these tools.
The confusion within the LDAS CVS repository over where sql files should be placed has been rationalized and corrected. There is now a single place for all database sql files instead of the confusion set of three that previously existed.
Testing of the frameAPI began in order to understand the failure modes that were exhibited during the MDC during heavy frame I/O loads.
The byte swapping bug for complex data that was discovered in the dataConditionAPI during the last MDC has been corrected. Now complex frequency series stored in the database can correctly be interpreted and used in datapipeline jobs.
Work began on adding a heartbeat monitor to each slave process running in a wrapperAPI job. The initial configuration will report a stalled node after 300 seconds of missing heartbeats and after 600 seconds without a heartbeat, the wrapperAPI job will be terminated by the mpiAPI. A dead lock problem that was detected while testing the new maximum memory usage throttle in the wrapperAPI was fixed. Also, the wrapperAPI will be getting a resource file to store start up variables and thereby reduce the amount of information passed on the command line. This will also allow the same wrapperAPI to be used in debug modes by a simple change to the resource
file.Work also began on added new functionality to the dataConditionAPI to be able to insert results from a database query into the datapipeline for use in the search codes.
The controlMonitorAPI now has a new monitoring tools which lets users see the different search codes by search user and shared object that are running on the individual nodes of the beowulf cluster.
Hardware Systems (Anderson)Vicere' and Lazzarini have almost completed an analytical model for how power grid correlations may be continue to exist even over long observation times due to the fact that 60 Hz is a frequency standard slaved over long time scales to GPS (nowadays).Caltech
(Dan Kozak) Some HPSS hand-holding, restarting Sammi and other servers. Adding tapes to storage classes. Repacking tapes decreased to nothing by the end of the week since we're out of tapes to repack on the Redwoods.
Solved (we think) Red Hat sendmail problem to allow Linux desktop machines to properly masquerade the return address on outgoing email.
Coordinated install of 9940 drives into new silo and install of ACSLS machine/software for silo.
The LIGO tape silo has physically moved its first tapes, albeit using CACR tape drives.
(Al Wilson) Hardware news - put a new computer on line, ldas-grid it is in the machine room at mill. Also I am working on a replacement for m27 a 2 Ghz box the old m27 will be used for visitors. getting a nasty uneven field problem on the new lcd in the machine room. Will continue to troubleshoot.
(A. Lazzarini note: this server is being used to provide an interface to grid resources being developed through GriPhyN)
Software news - still working on the http pages for the " how to make a ldas computer" and as always working on getting cfdef perfect.
(Stuart Anderson) Started the next major round of LDAS hardware procurement to support the Caltech production LDAS system (ldas-archive) and build the LIGO data archive system by planning and discussing possible technical solution with Sun Microsystems.
Rebuilt the one LDAS Alpha processor box with RH7.1 (ldas-alphadev1.ligo.caltech.edu) and released it for LDAS development
and general computing access.Livingston
(Shannon Roddy) Called cybernetics about the maintenance contract on the tape library. Will be purchasing the contract which requires shipping the library to cybernetics for inspection. Received the shipping box today so the unit should be going out tomorrow to cybernetics. Rebuilding admin here to allow for the disk to disk backups of various machines. I have a couple of finishing touches to do on this, but it is 95 percent complete.
Hanford
(Greg Mendell)
1) Continued work on the known pulsar search code DS0. Debugged code for writing ilwd output for the SNGL_DPERIODIC database table. Worked with AEI group to debug call to demodulation routine that creates longer time baseline DFTs from shorter base line DFTs. The code now compiles, runs without errors, and produces reasonable numbers. The next steps are to add additional error checking, add tests to verify that the code produces correct numbers, and increase efficiency.
2) Added db2 file system on LHO metaserver to backup script that runs daily on the LHO LDAS network.
3) Discussed with CDS and LDAS plans initiated by CDS for network security.
4) A faulty sensor indicated a filter change was needed on our Liebert AC unit. The sensor was replaced, and some adjustments to the tuning of the unit were made.
Data Analysis Activities
General Computing (Wallace)
MITNothing to report.
Hanford
(Christine) Most of the past week has been spent on procurement and budgeting issues. Moved a couple of computers around for new hires. Looked at the video conferencing setup.
(Tom) LSU is scheduled to come tomorrow (Friday) to install a router which will allow us to use our second T1 line. There will probably be a brief period when we are not reachable from the outside net, but probably not for more than a few minutes.
(Shannon) Installed some free security software on our windows 2000 server here in LA to block all of the attempted infections of nimda. We applied all of the patches to this box previous to the virus/worm outbreak this week, but just to be safe, I have blocked all connections on port 80.
(Mike)
-Engineering workstation West Bridge 3rd floor Dennis Coyne
-Mathieu, having problems with Ansys software, plus there was a virus
that Norton could not clean so put files into quarantine that included
multiple files on engineering and Mathieu's computer. I looked into
errors he was having when he launch his file using Ansys, I am still looking
into this problem. I have set Dr. Watson (internal program on the OS) to
create an error log. He has reloaded the Ansys software and rewritten
the file he is trying to get to work.
-Ran Norton anti-virus software to clean up Mathieu's computer and
Engineering workstation from viruses. So far everything seems to be working.
-Started working on reloading PC72 Amaldi server running IIS webserver
on NT4.0 SERVER.
-Completed PC72 Amaldi server, added a 15GIG hard drive, and reloaded
OS and IIS option pack 4.0.
-Helped Larry and Lisa installing additional shelves for new tape back-up
system.
-Worked on NT servers updating security and installing service packs
plus anti virus patches.
-Started Inventory on Laptops.
-Distributed a new 2Ghz PC to Millikan on the 6th floor.
(Wendy)
- Burned a few data CDs
- Working on loading/imaging laptops and rebuilding other PC's.
- Worked on inventory
- Moved computer and monitor from Lauritsen with Lisa and Mike
- Moved some PCs and updated/scanned with antivirus
(Lisa)
-Rebuilding becrux to upgrade the existing mail server. When
finished the unit will be swapped with the existing mail server.
- Put up a secure samba server at the 40meter. Works great. For
encrypted passwords you have to create a smbpasswd file. There are
a couple of tweaks to get that to work, otherwise it was very straight
forward. Had to re-enable encrypted passwords on the pc in their
martian network.
- Changed the nfs mounts in the 40meter again.
- Helped Chip out with some ghost/win2k issues.
(Mick)
Vacation
(Barbara)
-Restarted the DCC backups, fixed Amaldi web error, a couple of quick
web site changes, helped Rita, etc.
(Larry)
-Spending some time dealing with virus related issues. Most people
have not had any problems with this latest round of worm/virus attacks.
Getting ready to install another s/w pkg. that is to check for viruses
on the e-mail server.
-Resolved a number of purchase issues. Hopefully, the last iteration
for the SUN maintenance contract has gone through. The paperwork
for the fiber installation is in process. Have the final quotes for
the GigE back bone hub and will be going over that information with a group
of people before a decision is made on which vendor to go with. Still
working on different budget related issues.
-Resolved a number of printer issues. Most were simple issues with
one exception which was a print job that went into a loop causing a server
to be rebooted.
-Reworking the quarterly report for Albert.
-Setup a few more aliases for another group. Presently, setting up
the alias file so the groups can maintain their own lists.
>From: Helena Armandula <ahelena@ligo.caltech.edu>
"Q" measurements
Sent 2 (3"dia. x 1" tk.) substrates to Sheila Rowan to be measured.
She is leaving for Glasgow shortly, however, she'll perform the measurements
there. Expect to have them finished by the end of October.
There are two more (3" dia. x 1" thick) substrates available to be measured.
G. Harry, at Syracuse for the week, and S. Penn are making steady progress
measuring 2 thin substrates.
Advanced LIGO Coatings
Coating absorption studies will start within a few weeks.
We are signing an agreement with Gary DeBell from MLD to do the following coating runs on 1" fused silica aimed at studying the effects of different materials and annealing temperatures on absorption:
1) TA2O5/SiO2The samples will be annealed at 250, 300 and 350C. The runs can be done at 2 week intervals.
2) Nb2O5/SiO2
3) ZrO2/SiO2
4) TA2O5/Al2O3
Silicate bonding
Continuing tests to observe the effect of temperature on substrate/bond
stress.
>From: Janeen Hazel Romie <romie_j@ligo.caltech.edu>
Advanced LIGO Suspensions
Preparing for the Advanced LIGO Design Requirements and Conceptual
Design Reveiw tomorrow. Submitted viewgraphs to Peter Fritschel this afternoon.
>From: Mark Barton <mbarton@ligo.caltech.edu>
I've been working on an improved mathematical model of the Advanced LIGO suspension conceptual design, on the pattern of the one I did for initial LIGO. Unlike the Matlab model provided by GEO, this will be a fully 3D one in Mathematica, incorporating most of the features of the real thing except for violin and internal body modes.
>From: Riccardo DeSalvo <desalvo@ligo.caltech.edu> (Weekly 16 September 2001)
Both Lia and Florian stranded at Caltech because of the terrorist acts.
Charlotte
Calculated thermal profile of flex joints under different heat loads.
Calculated maximum allowable bend before breaking of joints.
Mathieu
More simulation of stress on silicate bonds, simulating both Glasgow’s
and home designed shapes.
Charlotte, Mathieu
Looking into introducing thermal noise and thermoelastic in Ansys
Lia, Riccardo
Acquiring and data analysis of early data analysis of creep.
Akiteru, et al. @ Hongo
More IP feed forward work.
Preparing for JPS (end of week)
Alessandro @ Pisa
Finishing the mechanics of the last horizontal accelerometer with micro-ground
flex joints. Preparing justificative papers and bids for NC UltraSound
sapphire cutting machine. Preparing to make more Sapphire flex joints
with old US machines. Testing first prototype for vertical accelerometers
for Newtonian noise.
For additional information about this report, contact sanders@ligo.caltech.edu