Weekly Report for Week Ending July 28, 2005

The LIGO Executive Committee Agenda for Monday August 1, 2005 will be:

(Meeting time: 10:30 am Pacific Time)  

  1. Announcements
  2. Comments on Weekly Report
  3. LSC Issues (Saulson)
  4. LIGO Lab Operations
      • Administration (Lindquist)
      • Sites (Raab, Zucker, Shoemaker)
      • Commissioning (Fritschel), Detector (Coyne)
      • Campus Research Facilities
        1. 40 Meter (Weinstein)
        2. TN, ( Libbrecht)
        3. LASTI  (Shoemaker)
      • Data Analysis and Computing (Lazzarini)
  5. R&D and Advanced LIGO (Shoemaker)
  6. CHANGE CONTROL BOARD/TECHNICAL REVIEW BOARD SESSION AS NEEDED

No open Change Requests

Special Items:

Special Announcements:

Weekly Report Highlights

LSC Issues (Saulson)

Minutes of LSC Exec Comm meeting

21 July 2005 1130 Eastern

Attendance: Bruce Allen, Patrick Brady, Joe Giaime, Albert Lazzarini, Peter Saulson (minutes), Rai Weiss, Stan Whitcomb, and Alan Wiseman and guest: Jim Hough

Report on Director Search (Hough)

Jim Hough reported that the Director Search Committee has held four meetings so far, and has made good progress. They will now move to weekly meetings to continue to make progress at a rate that will allow them to provide a list of candidates to the LIGO Oversight Committee by the end of August at the latest. He said that the committee had considered around eight candidates from within the LSC and 42 from outside the LSC, in addition to which two candidates submitted applications in response to the advertisement. Gary Sanders produced a job description that was helpful in recognizing strengths and weaknesses of individual candidates.  The committee has now reduced the size of its list of candidates from the LSC from the original eight down to three. At the moment, the number of external candidates has been reduced to 22, and more information is being sought to further the winnowing process. (This is expected to occupy the next two or three weeks.) Joel Tohline and Kip Thorne have also written to the astrophysics community, seeking further input. The committee hopes to present a list of no more than six names to the Oversight Committee.

Status of revised LSC Charter

The Charter Revision Committee (David Shoemaker, Norna Robertson, and Peter Saulson) has produced a mature draft of the new LSC Charter. It will be sent to LSC Council members in advance of the August LSC meeting, and will be proposed for approval at the Council meeting.  The committee has resumed work on the Bylaws, and hopes to have a new draft for discussion by the Council in August.

New MOU, attachment templates (Whitcomb, Saulson)

Stan Whitcomb presented a new set of templates for LSC MOUs and Attachments. (These can be found from a link "MOU Templates" on ligo.org.) All LSC groups (in the U.S., but not GEO) will sign the new MOU in this round, the boilerplate language of which has been brought up to date with present LSC policies. There are now more attachments, organized to be in closer correspondence to the way work is organized in the LSC. The text has also been rewritten to be consistent with current policies. These are the MOUs and attachments that will be signed in the August 2005 round.

Peter Saulson presented a draft of a policy statement on how the membership lists (Attachment Z) are to be filled out. The need for such a statement became apparent during the March MOU review, when reviewers compared membership lists from all groups. Several LSC Exec Comm members suggested minor wording changes, most of which were adopted.  [Since the meeting, LSC PI's have received an email including the Guidelines on Attachment Z and  pointing them to the new templates.]

Status of LSC Research White Paper

Peter Saulson described the status of the drafting of the new LSC Research White Paper.  First draft sections have arrived from DetChar, Lasers, Optics, Advanced Interferometer Configurations, and Stochastic Analysis. [Since the meeting a draft arrived also from the CW Analysis group.] All have been good first tries, each with a somewhat different take on presentation of prior accomplishments, present research program, and longer-term goals.

Joe Giaime asked whether it was appropriate to discuss research related to pre-Advanced LIGO improvements. Saulson said yes. Whitcomb pointed out that it is important to describe it carefully, and to use appropriate terminology.

A lively discussion was kicked off by Patrick Brady, devoted to the question of whether the White Paper should call out the activities of individual groups. The issue is the possible divergence between commitments that a group has made and the judgment (on the part of the Working Group chair, say) of whether there has been a substantial contribution from that group. Following up on this question was a discussion of different target audiences for the White Paper. One such audience is the National Science Foundation; particularly, we would like the White Paper to lay out the LSC's research program, so that proposers can point to how their specific proposal fits in with the overall research program. For this purpose, it is best to give a straight narrative account of the work of the LSC as a whole. A second audience is various committees and working groups within the LSC itself, in particular the MOU Review Panel. In the MOU review process, a group's accomplishments are to be compared with their commitments and with the place of their work within the LSC's research program. This involves frank judgments, and thus should not be made public.

One possible answer to the question was to have a public main body of the White Paper and a private appendix in which Working Group chairs gave their frank judgments about how contributions were being made; the latter would only be used for internal purposes. Another possibility is to not have such judgments be part of the White Paper at all, but just to have them be made as part of the MOU review process.

We also discussed how the PAC will use the White Paper and the reports of the MOU review process. The White Paper will be useful for seeing the context of proposals within the LSC research program as a whole. The PAC will also want to see the reports of the MOU Review Panel, to help it to make its rankings of proposals. Some members asked whether such use of the reports of the MOU Review Panel might mean that there would be NSF regulations to satisfy about the composition of the MOU Review Panel, or even that its reports would need to be supplied to the NSF.

Because of the delicacy of these issues, Rai Weiss suggested that we ask Beverly Berger for her advice. [Since the meeting, PRS spoke to Beverly about this. On the question of listing group activities in the main body of the White Paper, she said it would be useful, but not so useful that it was worth difficult struggles to create it. Beverly also clarified what the NSF wants from the PAC review of proposals. In her summary, that review is part of LIGO's direct response to the NSF for its own evaluation of LIGO-related proposals; it is the Lab's choice to ask the PAC to make the judgments about the relative merits of different proposals.  The NSF would be equally happy to have the LIGO response be made in any number of different ways. In particular, she says, the NSF would be happy if the PAC were supplied with the report of the MOU Review, but wouldn't need to see the MOU review documents itself, nor would it have anything to say about how the Review Panel operated.]

Patrick Brady also pointed out that our draft Charter states "The LSC will produce an annual work plan and report that will be submitted to the LIGO Directorate and subsequently be part of the LIGO Annual Report and Work Plan." This calls for regular updating of the White Paper, but doesn't require any particular information about the contributions of specific groups.

LIGO Laboratory Administration (Lindquist)

STATUS OF LSC MOUs (Lindquist)

  • Peter Saulson has issued a call for revised MOUs due Friday, August 5, 2005 in preparation for the MOU Review Panel meeting scheduled 22 August..

Non-LSC MOUs (Lindquist)

  • No report.

SITE TELECONFERENCE (Lindquist)

  • No report.
  • The list of assigned actions updated through May 26, 2005 will be found Here.

PROPERTY MANAGEMENT (Chargois)

>From: Ed Chargois <chargois_e@ligo.caltech.edu>

  • Nothing significant to report.

DOCUMENT CONTROL CENTER (Turner, Mak)

>From: Linda Turner - turner@ligo.caltech.edu>

  • No report.

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

  • Completed auditing all electronic "P" documents to confirm if they all are "OCR" ready when a text search is done on them.
  • Continued with organizing/processing of MOU's and Progress Reports.
  • Activity:

Week Ending

07/28/05

In

Out

Packages

13

10

Faxes

19

16

 

FINANCIAL SYSTEMS (Cunningham, Brambila, Kaufman)

>From: Esther Cunningham <esther@ligo.caltech.edu>

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

  • Prepared the RFP for the replacement of the water pipes for LIGO Livingston Observatory and submitted it to Allen Sibley to submit to the five vendors in Louisiana.
  • Attended the ASI teleconference on the request for a quote for the modifications to the design.
  • Trained John Hiroto as my backup to cover my absence during vacation.
  • Completed the monthly purchase order close outs and submitted the report.

>From: Florence Kaufman <fkaufman>

  • Attended a meeting with members of Caltech Finance Department to try to resolve issues related to incorrect PO balances at the task level when a Cost Transfer is made for contracts.  Matter is to be referred to Caltech's controller for resolution.
  • After many months, the systems error that resulted in incorrect charge of $64K to the Livingston Atomic Clocks account has been corrected.
  • Prepared a report for Hanford's Conference account.
  • Financial reports can be found at: http://docuserv.ligo.caltech.edu/~fireport. (For passwords contact Florence)

SUBCONTRACTS MANAGEMENT (Jasnow, Salone)

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

  • Nothing significant to report.

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

  • No report (vacation).

SUPPORT (Baldon, Hiroto, Lloyd)

>Irene Baldon

  • No report.

>Julie Hiroto jhiroto@ligo.caltech.edu

  • FastLane - Assisted with Fastlane date entry for Annual Report; report was submitted July 22.
  • Web pages - Updated broken links on the Talks pages 2001; new talks will be going up on the 2005 page

>Dorothy Lloyd

  • No report.
  • Jim continued with data entry in the LIGO database and helping out in the DCC.

PROPOSALS and REPORTS (Lindquist)

  • The final draft of the Annual Report has been entered into FastLane.
  • A draft Proposal for an Extension and Supplement has also been entered into FastLane.

DCC Steering Committee (Lindquist)

A written summary of the document management committee’s findings and recommendation has been prepared, reviewed by the members of the committee, and distributed to the executive committee.

CHANGE CONTROL/CONTINGENCY MANAGEMENT (Lindquist)

  • Change Request CR-050007 requesting additional funding for power and HVAC for LDAS at the sites was discussed during the executive committee meeting on Monday, July 25, 2005.  The committee recommended approval.  Minutes will be prepared and distributed.

HUMAN RESOURCES (Akutagawa)

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

  • The next Staffing Committee meeting is scheduled for Monday, August 29, 2005.

Quality/Safety (Tyler)

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

No report.

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

Summary of Commissioning Activities at LIGO Hanford Observatory (Landry)

Coming back online after the swap of the H1 ITMX, gate valves were opened Monday morning, and the 4k full IFO was locked in detect mode.  Progress was made until a magnitude 5.6 quake struck Western Montana at ~21:08PDT Monday.  Three masses across the two IFOs (H1 - ITMY, ETMX; H2 ETMY) showed evidence of being hung up on stops via static charge and/or mechanical coupling.  Sensor voltages and resonances were clearly atypical.  Thus, Tuesday morning there was concern that multiple vents would be required to fix optics.  First however, attempts were made to free the optics, by partially venting chambers, and shaking optic support structures.

Partial vents had been successful in the past, freeing small optics that were apparently hung up by static charge.  This had not been tried before on large optics.  First such attempts to burp gas into mid and end stations failed to free the optics, and next, shaking was tried.  We shook with PZT fine actuators (+/-40 microns from 10Hz down to 1/2 Hz), moving but not freeing the MY ETM.  Next, the Ryan/Worden method of sitting astride the crossbeam structures and shimmying, with a concurrent partial vent, freed first H1 ETMX, then H2 ETMY.  Thursday, H1 ITMY was also unstuck by the same procedure.  This fine piece of work saved us three vents and weeks of pumpdown time.

Read a summary of MY and EX shaking experiments, and John's conjecture that shaking is insufficient and pressure matters.

All gate valves had been reopened by Thursday late afternoon.  H2 has been routinely relocking, and H1 has also just fully relocked.  Thus at first glance it appears all three masses are in good working order.  We must confirm this with low noise spectra.

4K IFO

  • [this bullet entry by Bill Kells, regarding testing of the ITMX that was removed from H1 several weeks ago]  Bill writes: "The testing and analysis of the results for ITM07 are ongoing.  This has, of course, been made more complex by now due to the puzzling nature of the OTF results w.r.t the H1 measurements.  Further measurements here have been slowed by ongoing construction bouts in the OTF vicinity. We have been forced to consider a wider variety of diagnostic tests (for absorption) since our preliminary ones are not revealing what we had expected.  And, of course, the procedures we have been using are being scrutinized for loopholes."

2K IFO

  • The IFO was operated with WFS angular feedback to the masses only, and no optical levers.  WFS unity gains had to to be increased from 1-3Hz to 5-15Hz, filters judiciously selected, and gains ramped concurrently by scripts.  Low noise on the IFO was achieved only for four minutes in this proof of principle.
  • Currently, our best spectra on the 2k IFO yields high frequency noise that is shot noise limited, and mystery noise at 100Hz
  • The calibration of the 2k was updated with new sensing and open loop gain functions for Sensemon
  • The beam positions on the ETMs were off.  These were adjusted to center; while the positions looked better, the binary inspiral range dropped (increased noise at 100Hz).
  • photon calibrator work was ongoing through the week: photodiodes were calibrated and power meter uncertainty assessed.  Viewport reflectivities were measured.
  • TCS amplitude noise appears to be tolerable
  • the exact 2k REFL phase is not critical for frequency noise
  • more pinky tests were performed.  The coupling sites are less noisy but further improvements are possible.
  • RF distribution of non-resonant sidebands improved
  • saturation was reduced in WFS3 and 4
  • switching between REFL1 and REFL2 paths has little effect
  • the beamspot on the BS was moved purposefully to a place of worse 100-200Hz noise (let's not forget this fact prior to S5), in part to help track down the noise source

Outreach (D. Ingram)

LHO hosted the two-week WSU Tri-Cities course for teachers, "The Nature of Scientific Inquiry,"  between 7/11 and 7/22.  The instructor is LEN member Judy Morrison.  Our July WYP event was a showing of "Time Travel."  August events:  Perseid Meteor Shower viewing and the annual Public Lecture, given this year by Nergis Mavalvala.

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

No report.

Initial LIGO Detector Science & Engineering (Coyne)

CDS

see also the CDS weekly meeting minutes in the commissioning archives

CDS Software

no report

CDS Hardware

Rich Abbott

  • Planning agenda for two week trip to LLO starting 1 August 2005.  Items requiring immediate attention are:  Bulls Eye Servo checkout, preliminary checkout of Refl Beam Steering (RBS) servo, measurement and characterization of the 61 MHz NRSB chain, installation and characterization of new ISS.
  • Work continues on the ISS board (SN115) that is destined for LLO.  To date, a retrospective analysis has been performed that recommends a course of action to address failures in testing.  As an outgrowth of this, the following actions are being taken:  The schematic is being edited to agree with the latest design and a DCN generated to cover the changes, the bill of materials has been completely re-done to include all known updates and now reflects the current design, the test procedure is being re-written to capture lessons learned, the circuit board is being modified to include design changes that prevent spurious oscillations.  Only after this work has been completed can the testing of the board for LLO commence.  At this time, it is likely that the testing will occur next week while I am at LLO.  If this is the case, I will re-test certain key design changes at LLO to ensure a thoroughly airtight design.

Jay Heefner

Refl Beam Stabilization

  • Began prototype testing of epics software. Testing should be complete and the software ready for installation. We still need to decide on the location of the output DACs used to control the Piezo-Jena mirrors.
  • A block diagram of the system hardware and software should be complete by 8/29.

Ben Abbott

LSC RFPD:

  • The boxes for the RFPDs have shipped, and should be here any day now.
  • I am waiting for the parts for the RFPD to arrive from Digikey.  When they get here, they will be boxed up with the parts that I already have from other vendors, and sent to Screaming Circuits where the boards will be stuffed shortly.

DMT

John Zweizig

This week I have been working at LLO to perform the same upgrades as were done 2 weeks ago at LHO. So far, the new copper-cable switch has been installed and the GigE interfaces have been replaced in the frame builders and the two DMT Blade-1k machines. We expect to receive the additional interface cards needed for the new Opteron (poplar) and for delaronde today.

The Opteron (V40Z) machine had already been installed by Tom Evans when I arrived. I have since reinstalled its operating system and have done most of the steps needed to tailor it for use as a DMT machine.

Still remaining for this week is to set up the mirror of the DMT and development software from LHO, and to transition to the new configuration where the server machine (clearwater) is separated from the communications duties (to be retained by delaronde) and the remaining Blade-1k and Opteron machines are used for processing exclusively.

PSL/ISS

Peter King

Dave Grimmett and I have been testing ISS S/N #116, following the test procedure and recording the measured results.  I hope to give Rich some feedback about the test procedure; omissions, typos ... etc to help converge on a configuration a little sooner.

ITM07 Characterization

Dennis Coyne

Liyuan Zhange, Lee Cardenas, Bill Kells continue to measure absorption scans of the ITM07 (formerly H1 ITMx) but have yet to explain the observed high in situ absorption by the preliminary HR and AR scans. A bulk absorption scan is next.

Helena Armandula

A piece of the baffle glass was cut and sent for XPS-ESCA anaysis to Charles Evans and Associates.  Samples for FTIR will be taken next week. JPL will perform the test.

40 Meter Interferometer (Weinstein)

  • IFO commissioning:
  • The X arm is much noisier than the Y arm, and suspicion has been falling on ITMX, which doesn't seem to damp well. There have been several long-standing problems with ITMX: the beam is off-center by 6.5 mm horizontally (and a couple of mm vertically), the side OSEM appears to have near-100% coupling to POS, and all OSEMs have strong coupling to the bounce mode at 11 Hz. So, we decided to vent, to fix these problems.
  • Steve and Bob vented the 40m on Tuesday. There were problems with the MOPA and the cranes, detailed below, but otherwise, the vent proceeded smoothly.
  • Steve, Osamu, Dan and Ryan worked on ITMX during the vent. They moved ITMX 6.5 mm to the south. They rotated the side OSEM to minimize coupling to the POS and bounce motion at 11 Hz. And they adjusted the four face OSEMS to minimize couplings to the bounce motion. The adjustments proceeded smoothly, and indications are that they worked as expected. Many pictures of the suspension were taken.
  • Steve and Bob initiated pumpdown on Thursday morning. He tried to turn on the maglev turbopump at 100 mtorr, but it faulted. A while later, he tried again, and it worked - whew. Pumpdown is now proceeding well; with both turbopump and cryopump, the pressure is down to ~ 2 microtorr, and falling slowly.
  • Last Sunday night, the 40m PSL MOPA tripped off in the middle of the night, (7/26, 1am pdt) for unknown reasons. This is the 2nd time this has happened in the last year or so. It might be that some momentary (seismic) disturbance caused the PSL table enclosure interlock to trip, and then reset itself. Or it could be any number of other things. We need to log this, and/or, at least, indicate if a trip occured in the enclosure interlock.
  • When Osamu and Steve went to reset the laser, the electronic shutter in front of the power amplifier would not close. This also happened the last time the PSL tripped off. Osamu physically closed it by pulling at the metal shutter with a screwdriver, and thus was able to get it closed, and then turn the PA back on. The laser power supply should automatically close the shutter when there is an interlock trip, and it should close it when we hit the switch on the power supply front panel. It seems to do neither. (We did not try to completely power off the power supply or the NPRO). We don't know if this is a hardware problem (with the electronic shutter) or a "software/logic" problem; but once Osamu goes in with a screwdriver, the controls work and the shutter opens and closes on demand. Going in there with a screwdriver is a solution, but not a desirable one!
  • In order to determine whether the larger noise in the x arm compared with the y arm was due to different seismic noise, David Blair and Ryan Kinney made lots of measurements of the seismic noise with pairs of accelerometers. They measured the ratio of spectra ("transfer functions") and coherence, as a function of their spatial separation, up to 40 meters apart. In this way, they were able to measure the seismic velocities along the x arm and y arm. Data are still being analyzed, but there appears to be a significant difference in the velocities, resulting in coherent (common-mode) motion in the Y arm in the stack frequency range of 1-10 Hz, but less coherence in that frequency range in the X arm (leading to more differential motion and thus more noise).
  • Osamu suggested that David and Ryan use the suspension OSEMS as accelerometers, to see if there's a difference in the coherence at the suspended optics. They found the expected coherence roll-off in the Y arm, but anomalously low coherence from 0.2 Hz up in the X arm. Trying to figure out why; work in progress.
  • Dan and JuLi continue to work on a comprehensive diagonalization and tuning of all the suspended optics. They are trying to understand the anomalies in the resonant frequencies of the POS, PIT, YAW, SIDE, and bounce modes.
  • Ryan continues to develop the noise budget modeling, focussing on seismic noise and oplev servo noise.
  • Rana updated the Xarm and Y arm alignment scripts to dither the in-vac IFO PZT steering mirrors for the X arm and the BS for the Y arm.

IFO modeling and DC detection development

  • Marcus continues to refine his modeling of the DC readout output mode cleaner parameters. He's now looking at the mode matching from the AS port into the output mode cleaner, in parallel with Mike Smith.
  • Mike Smith is working on a final design of the mode matching into the output mode cleaner, and the mechanical design of the mode matching telescope and the output mode cleaner. Next, he will turn to a detailed parts list, and prepare purchase orders.
  • Jay continues to develop the design of the control and monitoring electronics for the DC readout system. The only big expenses appear to be the lockin amplifier and PZT driver for the output mode cleaner servo. We'll use existing channels for digital filtering and EPICS monitoring.
  • Ben continues designing the stand and mechanical parts for the in-vac DC Photodiode. The design is coming along well, and can be ready soon.
  • Ben continues to design the DC Photodiode electronics and work closely with Rana to be sure that it's appropriate for the currently envisioned needs.
  • Monica met with her LAL/VIRGO group in Orsay to sharpen the goals for her work here at the 40m. She will continue to continue to work on lock acquisition tasks, and on e2e simulation, using Matt's code.
  • Monica is also focussing on the links between 40m/AdLIGO and AdVIRGO. Mateo Barsuglia is also involved and may visit. Monica will start to write a technical report.

Electronics, controls

  • Ben installed the cross-connect wiring in rack 1X2 for the common mode servo. The new 3113 and XY212 are in place, and ready. The 64-pin cable comes in tomorrow, and I will make the three cables that are needed to finish the hardware install. I will make the necessary screens and change the LSC database this week. The LSC drawings have been updated. Need to document CMboard changes done by Osamu.
  • The front end CPUs (c1susvme1 and c1susvme2) started crashing. Rof and Jay traced the problem to some changes made to the susvme1.ini file in which several new channels were added for logging to frames, but in the wrong file. The problem is fixed, but Rolf is thinking of ways to make the code more fault-tolerant.
  • Ben expects a batch of new RFPDs to be ready for assembly in ~ 2 weeks. The 40m has requested five of them.
  • Mike, Larry, and staff swapped our temporary OKI printer (which turns out to not be a postscript printer, so the linux and solaris computers couldn't print to it) for the repaired HP printer.

Lab Infrastructure

  • When Steve went to remove the door on the ITMX chamber, the vertex crane didn't work. Ben and Bob replaced a fuse, didn't help. The problem appears to be due to overheating: if you power it down for a while, rather than keeping it on standby, before using it, it works. We will look at ways to reduce the problem.

Thermal Noise Interferometer (Black)

Since our last report, we have finished balancing the new mirrors in the North Arm Cavity (NAC), installed the shadow sensors in NAC, installed and balanced the new mirrors in the South Arm Cavity (SAC), installed the shadow sensors in SAC, and begun alignment of both cavities with the NPRO laser.

On the bond-noise experiment, Akira and Rick have identified the dominant noise sources, and they are able to accurately model the noise floor over a wide range of frequencies. The noise floor is, for the most part, a combination of electronic noise in the PZT driver, multiplied by the unusually-shaped transfer function of the PZT actuator, shot noise in the photodetector, and electronic noise in the photocurrent measurement circuit. Attached is a plot of the measured noise floor of the instrument (black curve) and a model of the sum in quadrature of these three noise sources (red curve).

We are now in the process of reducing this noise floor.

LASTI (Ottaway)

PSL

This week the power supply failed with the warning message HOTHSINK. After various restart attempts failed we replaced the Lambda power supply with the Lightwave Power Supply and the problem was fixed. Efforts continued to fully shakedown the LASTI PSL in preparation for our upcoming experiments

Triple Noise Performance

We have requested that the second triple modecleaner prototype be sent to LASTI to be installed facing the existing one. This will allow us to perform a series of tests that will investigate various control schemes with significantly improved displacement sensitivity.  Principally we plan to test the performance of Laurent's modal estimator control law.

Cleaning of the Solid Spacer

A lot of time was spent investigating the appropriated method for the cleaning of the solid spacer. In the end it was decided to follow initial LIGO large structure cleaning protocols with the addition of a pre-procedure acid etch to compensate for the lack of complete polishing of the surfaces. The cleanliness standard that will be adopted is 86a/100.

Data Analysis and Computing (Anderson for Lazzarini)

Simulation and Modeling (Bhawal)

Weekly Physics Meeting

Sany Yoshida described his e2e simulation work on the effect of Violin Modes in a locked cavity.

Triangular Mode Cleaner

(Hiro & Biplab) Keita's SURF student is running e2e to study Output Mode Cleaner and found the mode spacing simulated by e2e is different from a naive Modal Model calculation. Hiro and Biplab is working to solve this.

Simulation of 40m Interferometer

(Monica) I'm replacing old bundles with new alfi-bundles: the e2e package for the 40m is now easier to read. I'm also studying the LSC code implemented by Matt in his Advanced LIGO E2E package in  order to improve my control plant.

Advanced LIGO Cavity code

(Biplab) Used the 'FFTprop' matlab code for beam propagation that uses  'Adaptive Grid Size' method to write a code for the Advanced LIGO  arm cavity where beam-radius may vary from 6cm to 1cm (unlike in LIGO I  cavity where beam radius stays within 3.5-4.0cm everywhere). Next task is to compare it with ordinary FFT propagation. Probably it allows more computational speed because the needed number of pixels would be less than ordinary FFT propagation.

modeler

(Hiro) Still working on the coding of the fast dual recycling module as the primary programming. FFT design is also going discussing with interested people, including Ken Ganezer.

Alfi

(Bruce-last-week)

  • Multiple port deletion implementation.
  • External node view window size fix.
  • Working on bundler I/O name editting.

(Bruce-this-week)

  • Continuing work on external node view window size fix (PR 488).
  • Completed bundler I/O name editting (PR 477).
  • Fixed port movement code and documentation (PR 484).
  • Junction networks now redirect their data flow on connection to a source to a different junction in the network (PR 314).
  • Continuing work on other PRs in PR database.

(Melody) Continuing with fixing the PRs.  Fixing PR 415.  Investigated possible solutions for PR 483 - "check into new way to display java remotely".

LDAS Software Systems (Blackburn)

LDAS

The LDAS 1.7.0 release is being pushed out today. This release has better RDS creation performance and several fixes to the diskCacheAPI. Over the weekend, a new issue with threads disappearing in the diskCacheAPI was discovered at LHO.

The case of this was (and still is) unknown, only that it didn't occur in the 1.6.0 release of LDAS. A workaround to detect the disappearing thread has been added and been shown to properly behave in the few cases where this problem has occurred after the detection code was added. We will be working hard to learn the source of these disappearing threads.

An issue was discovered in the controlMonitorAPI whereby it is mapping all users for certain commands onto a staff developer's LDAS account. The source of this has been tracked down. A problem report has been filed and a fix has been proposed for the next release.

TCLGLOBUS

A total of 64 functions from globus_gass_transfer.h have been SWIG-wrapped.  Of these, 35 functions (client-initiated, send/receive bytes, and set/get attributes) have been tested.

Fixed GASS Transfer register get/put/append SWIG-wrapped functions because they were incorrectly SWIG-wrapped in the first time.

Still modifying GASS Transfer server-initiated test case. GASS Transfer server implementation has to be written from scratch since there is no mechanism to create server object like the one in XIO or I/O package.

Added 10 Robodoc function documentation for GASS Transfer.

GRIPHYN/IVDGL/OSG

LIGO was well represented at the OSG Roll-Out event in Milwaukee last week. LIGO had three of its sites (UWM, PSU, and CIT-ITB) up and running for the event. The meeting brought together OSG Consortium members from ATLAS, CMS, LIGO,

SDSS and other new members joining since the humble beginnings of GriPhyN and iVDGL. The OSG council and interim executive board met on Friday to review preproposals and discuss funding for OSG.

The iVDGL annual report is due this week. LIGO has been asked to present its activities as a Tier II center, activities and involvement in OSG and experiences running applications on the OSG in the report.

The LIGO CIT ITB test site has been added to the collection of ITB sites that are tested daily with a Grid Exerciser (gridex) managed by the OSG consortium. The statistics from gridex have demonstrated several problems with file permissions and Condor configuration which have resulted in errors in the Condor log. Most of these have been tracked down in the last week and eliminated.

An initial test of executing a simple Globus job, on the thirteen sites recognized as online on the GridCat ITB web site, returned proper results on twelve out of the thirteen resource providers.

A LIGO investigator produced a detailed explanation of an inspiral work flow based upon an OSG demo. Future work will be to use the Pegasus planner and the inspiral custom code to develop a LIGO grid application that can run on OSG ITB sites that support both Condor and VDS. The url for showing the results of submitting the inspiral search code onto the OSG Grid is:  http://www.lsc-group.phys.uwm.edu/lscdatagrid/griphynligo/osg_demo.html.  

Work has begun in reviewing the code and documentation in the Virtual Data System (VDS) as some components of the VDS are required for the inspiral work flow. This primarily involves learning how to use the Pegasus application from ISI.

LDAS System Administration (Anderson)

Caltech

(Dan Kozak)

  • Handed off LLO /usr/bin/true corruption problem to Igor (still unresolved).
  • Got STK to replace failing 9940 power supply.
  • Fixed up pfns in RLS for /archive/postS3 to /archive/frames/A3 move.
  • Received last (for now) of replacement 3510 disks (i.e. we're all caught up and there haven't been any failures in almost a week) and shipped back all outstanding drives to Sun.
  • Noticed dead drive and old style (2 RAID 5 LUNs) configuration on LHO fb0_frames 3510.  Passed the info on to Dave Barker.
  • Continued /archive reorg and LHO/CIT sync.  Did some /archive reorg at LHO (with Ben's help) towards this end.

(Stuart Anderson)

  • Installed latest SAM-QFS patch (4.3.15) for initial testing.
  • Helping out with LDAS-1.7.0 release testing and rollout.
  • Investigating problem with V880 power supply alarm tripping.
  • Working on Synchrotron computer facility upgrade.

MIT

(Keith Bayer)

  • A/C fixed in ldas lab  - cluster machines back on-line.
  • Data disk in node 41 died and was replaced.
  • Ordered new 3ware raid cards for pcraid#3.
  • Upgraded cluster to 2.6.12-1.
  • Cluster now automounting data disks (causing much less traffic on network).

Livingston

(Igor Yakushin)

  • Discussing with Robert Schofield details of HVAC seismic isolation; discussing with Allen, Rusyl, Shannon, Mike and Joe the details of LDAS upgrade and LDAS move.
  • node39 died; most likely power supply failure.
  • Called StorageTek to find out how to move the tape robot and whether they provide any support for it; they can do it for $1200 but probably we can do it ourselves as well: tapes, tape extension need to be removed, drives should be switched into the locked mode before moving.
  • running badblocks on the nodes revealed several bad drives. However badblocks and dd do not necessarily agree on which drives are bad.
  • LDRed from PSU SG20_S4 and SG21_S4 to LLO, LHO and CIT.
  • Interviewed several candidates for LDAS/GC position.

Hanford

(Greg Mendell)

  • The CCB has approved the upgrade of power and air conditioning in the LDAS room at LHO. This will allow an increase in the number of cluster nodes from 140 to 210 before S5.
  • I have tested createRDS jobs to support the release of LDAS v1.7.0.  The tests show that createrds generation continues to work flawlessly with the new release of LDAS, and is 20-30% faster.

(Ben Johnson)

  • Worked on a problem with the LHO state vector. The common mode bit was no longer being set due to a seemingly inocuous change to lock script.
  • Started hard drive scan of whole cluster. I will work up a chart with the retults of what to replace and how.
  • ldas-pcdev1 has finally been moved to the new server. It is currently running FC3.
  • Working on auto-archiver for AstroWatch. It should be able to work at both observatories.
  • Renamed and/or added A3 PFNs at all 3 labs.
  • Changed a user's certificate subject per his request (received a valid signed email from the user).

Data Analysis Activities (Anderson)

(Greg Mendell)

There were StackSlide code reviews in the past week.  These took place July 22 and 28 2005at 9:15 PDT.  The StackSlide review page is posted here (access is as per the usual PULG investigations pages):

http://www.ligo-wa.caltech.edu/~gmendell/PULG/StackSlideUtilities/review/StackSlideReviewPage.html

(Igor Yakushin)

  • Siong and I finally figured out why waveburst results on LIGO-GEO data did not make sense: it turned out that S4 GEO frames start from non-integer number of seconds (they have 15000 ns offset). Waveburst assumed that a start time of a frame is always an integer. As a result there was some discontinuity in the time series, processed by waveburst, on the boundary between GEO frames that resulted in excess of triggers each 60 seconds and high noise variability. I have fixed waveburst to handle non-integer start time of frames and so far at first glance the new LIGO-GEO waveburst triggers look reasonable (but there is still some work left to do to make sure).
  • Generated LIGO only production triggers with the version of waveburst in which a minor bug in the calibration (that was discovered during the code review) was fixed. Two waveburst modes were used: 64-2048 Hz and 64-4096 Hz. The study is under way to check whether these sets of triggers overlap in the common frequency subband.
  • Running waveburst on SG20_S4 and SG21_S4 MDC frames.
  • Continue testing waveburst on LIGO-VIRGO simulated data.

(Peter Shawhan)

  • Worked on responses to comments from the referee of the S2 untriggered LIGO-only burst search paper.
  • Worked with SURF students Sarah Caudill and Sebastian Cassel.
  • Reviewed pulsar analyses.
  • Released a new version of the LIGOtools 'dataflow' package on July 15.

(Antony Searle)

After further optimization of the code, began running on ldas-pcdev1 and on real data with real glitches.  Quite a few bugs with normalization and threshold found, worked very closely with Shourov all week on these.  Consequences of these simulations not clear yet; need to understand what the glitches are doing.

General Computing (Wallace)

MIT:

(Keith)

  • Working on windows XP x64 flavor for CAD desktop.  Installed Algor and Solidworks.
  • Still working on Nastran.
  • Primary nameserver went down Tuesday - went around and switched nameserver lists on some machines to point to backup nameserver.
  • Working on spamd filter (as time permits).
  • Investigating wireless connection trouble in NW22.

Livingston:

(Shannon)

  • Attending USENIX conference.

Hanford:

(Christine)

  • Network usage can be seen at http://www.ligo-wa.caltech.edu/~christin/mrtg/198.129.208.1_198.129.78.122.html
  • Setup two new laptops.
  • There was another error condition on the main network router.  This time it was on the card that is connected to PNNL.  PNNL reported that the problem was not on their end.  A re-boot of the router cleared the error condition.  Other than the error alarm light and the fact that the interface card was down the router was not reporting any other errors.
  • Installed the latest printer drivers on the reception office computer.
  • Continuing preparation for LSC.
  • Purchased a 10/100 interface adapter for the router to be used with the backup network connection.

CIT:

(Christian)

  • Finished updating the laptops that are traveling to Hanford Observatory with the latest security patches and virus definitions.
  • Millikan: replaced drum kit on Irene Baldon's printer.  Added additional memory to Albert Lazzarini's new PowerBook laptop.
  • Downs: Finished inventory of computers and updated the LIGO IP & Inventory Database.
  • Continued ongoing onsite software & phone support.

(Mike)

  • Ken Mailand: I finished up Ken Mailand's workstation. Swapped out his hard disk and dumped a ghost image to restore his OS, apps, & data.
  • Added more visitor/surf student's to the wireless access point list.
  • PDMWORKS: Works with Oddvar on some issues with the vault. This was a directory permission issue. I ended up having to manually remove a directory and reset the file permissions on the vault in order for Oddvar to add updated drawings to the vault.
  • Worked the Spam Filters with Larry Wallace.
  • GariLynn: Bad hard disk. Received a replacement drive, and will start reloading this laptop. I spent a lot of time recovering data from the unit.
  • Phil Willems: Backed up his laptop, before he went on travel.
  • Barry Barish: Installed a bigger hard disk in his office workstation.  This included ghosting his old drive, installing the new drive, and finally dumping his ghost image to the new drive. I also updated GC software.  New laptop, I received his re-placement hard disk and battery. I tried dumping a ghost image to the new drive, but failed. (Due to bad sectors). This is a on going project.
  • Additional onsite user/phone support.

(Veronica)

  • LIGO:  Website updates.  High-resolution images for a publisher.  Roster database updates.  Updates to the PAC website.
  • LSC:  Website updates.  Mailing list updates.  Updates to the papers under review webpages.  Updates and troubleshooting of the August meeting website.
  • Project Science:  Support of the website transfer over to the ITS hosting.

(Bruce Sears)

(BS) Ilog Development:                               (1.0 days)

  • General testing of new version and code cleanup.
  • Fixed bug which caused old-style entries with only an image (i.e., with no text) to not display the image.

(Larry)

  • Worked a number of procurement issues. Purchased a couple more notebook computers for people. Also, purchased a number of computer supply items.  Working on a couple of maintenance contract renewals.
  • Assisted a number of SURF students with different problems. Setting up new software packages and assisting in file conversions were the major items of work.
  • Setup a couple more new accounts for long term visitors.  Going through the mail aliases, there is a need to adjust a couple of aliases in order to accommodate long term visitors.
  • Worked with the DCC on a number of issues. The final report with the recommendation of which vendor to go with and file moves were the items taking up the most time.
  • Worked a number of e-mail issues and continue working on filter modifications.
  • Still working on the air-conditioning issue for the computer room. PMA is now taking a look at replacing the existing system with a newer larger capacity unit.

Advanced LIGO and Supporting R&D (Shoemaker)

Systems and Management

Advanced LIGO Project Management

from Carol Wilkinson

Progress updates for Advanced LIGO subsystem development for the period from May 1 to June 30 have been completed and are available on-line. Sub-system leaders will be asked to work up Estimate-to-Complete the development portions of their sub-systems – due end of July.

Meetings & Reviews

Future near term planned meetings & reviews are indicated in the table below.

  • Report from SUS Requirements Update Review held on June 15, 2005 is available: M050216.00.

AOS Stray Light Control DRR/CDR has been delayed from Sept. 28 to ~Oct 19.

 

Date

Subsys

Review

Topic(s)

Enabling event(s)

Schedule motivation

 

Jul 7
8:30-10:30 PT

SEI

BSC Critical Design Review 3

review basic requirements, interfaces & dynamic coupling

available analysis/reports

timely decision on proceeding with SEI/BSC prototype for LASTI for integration with the SUS quad prototype

Report in progress

Jul 11-13

SYS

SYS Mtg

CDS Infrastructure & HAM Isolation Requirements

 

 

Report in progress

12-Jul
8-11 PT

SUS

PDR, Review 2

Electronics req & design; Focus is on the front end electronics (UK) -- limited Digital controls/electronics (US) review

 

 

Report in progress

Jul 19
8-10 PT

ISC/40m

40m DC Readout Review

DC readout experiment

 

 

Report in progress

~Aug, 05

SEI

HAM Critical Design Review

Recommendations w.r.t. HAM prototype development based on ETF results

Completion of SEI/BSC critical design reviews; LSC review of ASI HAM configuration design

timely decision on proceeding with SEI/HAM prototype

 

~Sep

SUS

PDR, Review 3

Quad design

Completion of the quad controls prototype assembly;

timely transfer, to RAL & UB efforts, of lessons learned from the controls prototype

 

~Nov

SUS

PDR, Review 4

Quad Installation

Completion of installation at LASTI

Inform the UK final design & noise prototype design effort ASAP

 

~Dec

SUS

PDR, Review 5

Triple design

Available SUS/US staff

Enable SUS/US final design phase

 

~Feb

SUS

PDR, Review 6

quad controls prototype test results
ribbon process/design

completion of LASTI testing

timely incorporation into final design effort on the noise prototype

 

TBD

SUS

PDR, Review 7

BS, FM/ITM SUS design
RM design
non-cavity SUS

design work completion (has yet to start on FM/ITM, not mature for RM)

 

 

~Oct 19

AOS

Stray Light Control, DRR/CD

 

SYS PDR?

primavera late finish 6/15/05

 

TBD

AOS

Thermal Comp., DRR/CD

 

SYS PDR?

 

 

~Oct

SYS

PDR, Review 1

Engineering & Implementation ('generic') Requirements;
Interfaces
Revised Optical Layout
Optomechanical Layout

completion of generic requirements definition; completion of first draft of ICD; revision to optical layout; establish integrated opto-mechanical equipment layout

timely system level definition enables/helps define subsystem reqmnts & design

 

~Dec

SYS

PDR, Review 2

CDS Infrastructure
Stable Recycling Cavities
Lock Acquisition
Modulation Scheme
Power Induced Instability

Sufficient CDS requirements & concept work (also 7/11-13 mtg)
E2E Modeling for AL
40m Progress on Acq. & Mod.

CDS Infrastructure is key to subsystem electronics req.
Stable cavity is key to IO MMT design

 

~Sep

IO

PDR Review 1

Faraday Isolator

SYS PDR?

 

 

~Jan

IO

PDR Review 2

Electro-Optic Modulator

 

 

 

~Mar

IO

PDR Review 3

Mode Matching Telescope

Determination of whether a stable recycling cavity will become part of the AL baseline

 

 

~Oct

COC

PDR

Review 1

 Metrology

 Review and select  vender and in-house metrology

 

 

TBD

COC

PDR

Review 2

 

SYS PDR?

 

 

 

Seismic Isolation

From: Ken Mason kmason@ligo.mit.edu

SEI Structure

We have met again with ASI on the redesign required to soften the springs. They are working on a quote which they expect to have to us this week. They are aware we are looking for a completion by 9/1/2005.

A requisition has been submitted for the seismic/quad test stand.

Parts have been received to complete and test the blade calibration

From: "Joseph A. Giaime" jgiaime@ligo.phys.lsu.edu

Weekly SEI meeting, 22 July 05

Announcements:

  • There was a telecon this morning with ASI, in which we agreed to a list of deliverables for the spring/flexure modification work.  We expect a firm-fixed-price bid sometime next week.  A LIGO CCB proposal would follow an acceptable bid.
  • Dennis is now able to produce state space models from FE models.  He has found matlab code that reads modal analysis data from IDEAS and exports ss models.  Perhaps other FE programs can produce appropriate intermediate data as well.

LASTI lab work

  • Rich has remeasured the actuation -> geophone coupling fitting parameters versus amplitude, now that the rubbing problem is fixed.  He has 7 local displacement sensor loops closed, and drives the 8th (horizontal) actuator.  The fits are excellent for any particular run, but the crossover between horizontal and tilt changes with amplitude.  See his LASTI log entry on July 18.
  • Today's log (22 July) contains an entry that more systematically compares drive level and tilt coupling frequencies.  He adds another coupling parameter, and now  L4C signal = L4C Horizontal Response*(1 + beta/f + alpha/f^2)*Actuator Response.  So a set of constants alpha and beta can correct the geophone over a wider range of actuation amplitudes. The new HEPI code recently installed by Rolf is compatible with this approach if we decide to use it at LLO.

Addressing the HAM SEI structure resonance issue, there are a number is useful log entries:

  • Jan 7 LASTI Log: HAM HEPI resonances measured and discussed.
  • July 12 LASTI Log: HAM pier power ratio and TF measurements.
  • (Today) July 22 LASTI Log: Laurent has carried out some FE modeling, looking for the 9 & 12 Hz resonances seen in the HAM external seismic structure.  He looked at the crossbeams and support tubes.  He puts in mass corresponding to the support table, a rigid spacer, and the optics table.  The crossbeam ends are clamped rather than free as they should be.
  • Also, see entry 509 (22 July) of SEI Log: An early draft of Dennis's analysis of the HAM support structure integrated with the stack, etc.

Ken has put bellows into his BSC FE model.  Putting the 'dirt' below the slab is still in progress.

Electronics:  Jay awaits our choice on which electronics design we want to try first on the modified GS-13.

Suspension

From: Janeen Romie <romie_j@ligo.caltech.edu>
Advanced LIGO Suspensions

Stuart Aston from the University of Birmingham has joined us this week. He’s brought a prototype of the final design hybrid osem. He’s been working with Bob Taylor on the cable harnesses for the quad. He’s also been helping us partially disassemble the quad and reassemble it.

We had a discussion with Calum, Stuart, Jay, Mohana, Bob and Helena on wiring up the electrostatic drive. Jay will create a wiring diagram for Bob to use. He’s researched soldering method to use with the gold mask that does not use flux. He’s buying a sample of a gold coated fused silica optic from Edmund Scientific to use as a test piece.

The spacer parts for the mode cleaner at LASTI are with Bob Taylor for cleaning and baking.

Had a meeting with Dennis, Oddvar and Calum on taking over on the installation fixture design and fabrication while Oddvar is on leave. We will meet with local machine shops to get an idea of the cost and schedule. Most shops now accept Solidworks parts files, along with a partially dimensioned drawing, so that will help things along.

Had a meeting about sending the second mode cleaner triple to LASTI. Helena has done a quick inventory of cleaned and baked hardware at the 40m to support this.

Helena and I organized all of the hardware and tools in the Synchrotron lab last week.

From: Jay Heefner jay@ligo.caltech.edu

AdL SUS

Began layout drawings for LASTI quad controls using LIGO-like controls. The system will be based on PCI ADCs and DACs and should be much less expensive than our present VME- based systems.

Gin Gin

Continued discussions with David Blair concerning digital controls for their SOSs and cavity length and alignment controls.

From: Ken mailand kmailand@ligo.caltech.edu

Making simplified S/W drawings of the Adv. LIGO optical component assemblies for import to Zmax, for Mike Smith, and converting Mechanical Desktop LHO full site layout to S/W

Core Optics

From: Bill Kells <kells@ligo.caltech.edu>

Still working hard this week on the parametric instability issue(s).  Finished a review of one of the Perth papers (channeled back via P. Saulson to authors....... still on good terms !). Some very interesting revelations have come up on both the numerical details of determining instability thresholds, as well as some aspects of the fundamental theory. We are all trying to reach a new plateau of understanding (vis-a-vis AdL) by the LSC.

Pre-Stabilized Laser

From: Peter King pking@ligo.caltech.edu

AdvLIGO PSL

I received a new quotation for the 300 mW Innolight Mephisto OEM version.  The labor hours and costs are being re-worked, without reference to the existing cost book.  The estimates are based on VME hardware and our current implementation of cross-connects as that is the best thing I can base such numbers on.  Given our current emphasis on documentation and testing, their allocation has been included in the labor estimate.

Auxiliary Optics

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

OPTLEV

Ben Abbott hooked up the electronics for the QPD, and we are reading X-Y voltages from the QPD when the input beam is moved in angle. Aabeg has modeled the addition of an input telescope for changing the input spot size. The beam will be expanded by the ratio 5/3 to produce a 2mm beam waist at the output of the  Oplev 3, 14meter EFL receiver lens.

SLC

The AOM modulator approach was abandoned because we didn't have the proper driver to modulate the beam intensity. Instead, Shasta is using a conventional chopper wheel to modulate the intensity. She is in the process or re-aligning the optical paths to correspond with the un-deflected beam through the chopper.

Other Laboratory R&D

From: Riccardo DeSalvo desalvo@ligo.caltech.edu

Marco and John

Gave a presentation of the MH interferometer workings and recent results.  From now on Marco is on strict writing mode (Amaldi paper, LIGO talk, LSC presentation and finally his thesis.  John will take over in the interim in the lab’s operations.

Tomorrow Juri will give a rehersal of his SPIE presen tation on the MH interferometer. We will also have a meeting with Jeam Marie Mackowsky (visiting Caltech) on the future of the MH project.

Barbara

Back for the week to finalize the Amaldi paper with Marco, Juri and Riccardo.

John

I tested and refined the new data acquisition program by taking some frequency spectra. The new mode matching design was completed. The two lens solution has been abandoned in favor of a simpler one lens option. This solution is thought to be more stable and will be simpler to implement. The lens required has been ordered from CVI. All cavity mirrors were analyzed by Garilynn Billingsley. It was found that both flat mirrors (and possibly the MH mirror) were deformed due to pressure from their mounts. A solution has been designed and will be tested this week once the flooring has been removed from the sub-basement.

Justin, Sean,

Last week we finally successfully loaded a 1kg test mass on the lower mono-crystalline silicon flex joint. In doing so we have found that the quality factor ratio for silicon maraging is 5.78. This is surprising because eliminating one of the joints should have halved the losses and doubled the Q factor. Evidently the bottom joint that we changes was hosting much of the losses for the investigated (modified violin) mode) Next week we will attempt to loading the 1kg test mass on both the upper and lower silicon flex joints.

Juri

I modified my FFT simulation program to model a folded three mirrors cavity. In this way we can run more realistic simulations for studying the behavior of our Mexican hat cavity. In particular we can study the effect of the misalignment of the three mirrors on the resonant modes of the cavity and compare the simulated results with the experimental data. Moreover I’m including in the simulation program the measured mirror maps for both the input and the folder mirror. Using these maps, we want to analyze the impact of the mirrors deformation, due to the mechanical mounting, on the beam shape.

Alberto

I’m still waiting for my pieces from the manufacturers and I hope to have them in the next few days. Then we will be able to begin the setup of the apparatus. Meanwhile I’m studying the way to build the arm according to the transfer function of the system in order to obtain the right counterbalance of the payload. Because of the complexity of the calculations involved Ilaria and I are going to make a numerical estimation of the same transfer function via an ANSYS simulation and then do a comparison between the results. We would like to have a faster way to predict the reactions of the system to different solicitations.

Ilaria

Arrived in Caltech, after got to know the place well, I started working with the Ansys program. Since I have never worked with Ansys before, I’ve begun to sketch some examples to understand how the program works. So, I designed a few shapes with another software, Solid Works, I imported them to Ansys and I tried to make some simulations. In this first week I also read some paper about the Inverted Pendulum to understand its operation.

Chiara

I have worked in the machine shop to make aluminum supports for the three inverted pendula that are going to be pedestals of the system.

Maria Paola

My job is to design a wireless control of a stepping motor, through the use of a laser diode (whose output will be modulated with pulses) and a photodiode. The produced voltage will be increased using a transformer and rectified with a diode bridge. Finally, a capacitor and some switches will be needed to feed the stepping motor, whose steps can be controlled by the frequency of the input signal. I started working on transformers, and making an approximate calculation of how many coils are needed for the primary winding and the secondary one, knowing the input current and power, the permeability of the ferrite pot core to be used and the turns ratio I want to obtain. I have ordered and received the laser module and the silicon detectors right yesterday: during the week I began to build a transformer (with roughly the numbers of coils I found from my calculations) and to test it using a simple led and photodiode, with pulse signals. The gain I obtained was about 15 without any load.

Francesca

The acquisition card was not blasted; the signal was too noisy because the acquisition scan/rate of the program was too low. So, in order to amplify the scan/rate, I modified the lab view program (deleting everything that was wasting memory [as graphics]), in order to speed up the scan/rate maintaining the real time acquisition. I added an RC filter between the output of lab view and the input of the amplifier. I controlled that the dephasing added to the wave by the RC filter was negligible (at 100 Hz the dephasing was about 48 degree, at 10 Hz the dephasing was about 3 degree and since I have to work at 1 Hz, I considered this dephasing acceptable). I completed today the assembling of my test.

Anamaria and David:

We're almost done with the setup for our experiment. We will move it into a very quiet room. We've been dealing with little things that come up such as random connecting pieces, etc. The data acquisition has been setup from before so that part should not take long. We however need to setup the excitation at the same time of the four materials.

Riccardo.

Working on the bid request for the HAM SAS fabrication.

Valerio

Hacked up a first (very coarse) model of the HAM SAS.

For additional information about this report, contact Stan Whitcomb or Phil Lindquist