Weekly Report for Week Ending April 5, 2007

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

Past Weekly Reports

Special Announcements:

Weekly Report Highlights

LSC Issues (Reitze)

the S3/S4 known pulsar paper (gr-rc/0702039) and
the S4 radiometer paper (astro-ph/0703234)

LIGO Laboratory Administration (Lindquist)

DOCUMENT CONTROL CENTER (Turner, Mak)

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

• Presentations from the recent LIGO/VIRGO Scientific Collaborations Meeting continue to trickle in.
• Continued to process talks from various past conferences.
• Burned numerous cd copies of recently scanned files.
• Scanning Update - Progress continues on scanning of all non-electronic "L" category documents on file.

Update to Current Document Management System (Lindquist)

No report.

FINANCIAL SYSTEMS (Funaro, Brambila, Kaufman)

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

• For ACCOUNTS PAYABLE HISTORY Press Here.

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

• Prepared a list of the expired subcontracts and submitted to E. Jasnow for review and decisions on close outs or renewals.  Updated Ed with upcoming renewals on contracted individuals.
• Reviewed the blanket orders. Two orders were closed out and there is one blanket order still open and expired.
• Completed the change to Thorlabs and coordinated with vendor.
• Completed the fund transfer on the subcontract so that the POETA LIGO.I2U2 task 1 can be closed.
• Resolving issues with vendors on invoices for LLO that have billed sales tax.
• Working on the change order to Southern Enterprise.
• Coordinating with end users on expired maintenance agreement orders with Dynamic Systems that should be renewed within the next week.

>From: Florence Kaufman <fkaufman>

• Requested new PTA set up for Kent Blackburn's new Award from the University of Wisconsin Madison.
• Requested new PTA has been established for the I2U2 Award.
• Prepared Cost Transfer to move expenditures from the old I2U2 Award to the new Award.
• Prepared a Fabrication Equipment Request and PTA Set Up Form for the Pathfinder Input Test Masses.
• 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>

• A funding modification was prepared to add the final amount to the MIT contract, $2,000,000.

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

• Work continues on drafting system requirements documents for both subcontracts and subawards for use in both the Advanced LIGO Cooperative Agreement and the Operations Renewal Cooperative Agreement.  The goal of the drafts is to separate the two categories, which are currently intertwined in the language of the NSF draft documents.
• It has been agreed that the items to be shipped to Australia National University (ANU) will be on a loan basis, and not as a gift.  The status will be reviewed after three years to either extend the loan or have the items returned.
• Two review packages for the NSF are being prepared on the Baseline SEI and the HAM-SAS, with the one selected actually being sent to the NSF.  The two packages are being prepared simultaneously in order to try to expedite the review process.

PROPOSALS and REPORTS (Lindquist)

I am maintaining a web site containing information and useful pointers for the preparation of the proposal for continuing operations (FY 2007 - FY 2013).  User IDs and Passwords have been provided to those who asked.

The end of March report for the NSF is due next week.  I have distributed an outline and requests for submittals.

CHANGE CONTROL/CONTINGENCY MANAGEMENT (Lindquist)

• There are no open change requests.

HUMAN RESOURCES (Akutagawa)

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

• No report.

Quality/Safety (Tyler)

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

At the LIGO safety committee meeting this week, we agreed to adopt the proposed roles and function statements prepared by Caz Scislowicz (Caltech Safety Office).  These will be incorporated into the revised/updated LIGO safety plan.

The committee was not able to reach agreement on how to establish an "incident reporting threshold".  One of the main issues was if it was necessary to report all incidents or if some "minor-types" could be ignored and not reported?  At this meeting, the committee's conclusions were: that some reporting guidelines would be useful, rely on the "site-safety-officer" as the main "point-of-contact" to screen/advise/decide if a report was required, and the committee would assess the incident reporting to determine if it was satisfactory or needed to be revised.

The Livingston safety review will be conducted on the 15th and 16th of May 2007.

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

Summary of S5 Activities at LIGO Hanford Observatory  (compiled by M. Landry)

This was a quiet week with good duty cycles : H1 - 88%, H2 - 87%.  The range on H1 remained ~15-16Mpc during quiet running periods, while H2 continues to languish below 7Mpc most of the time, often at~6.5Mpc.  Quakes (Azores, Afghanistan, Solomon Islands) were a major source of unlocking events.

Some S5 highlights from the LHO elog are bulleted below:

• summaries: Tuesday maintenance, CDS maintenance,most recent range & duty cycle weekly (we're nearly 80% there), IFO maintenance
• the stability of the H1 awg processor continues to be a problem - we lose hardware injection opportunities for bursts and inspirals, or the pulsars stop, until h1awg0 is rebootetd
• the biggest quake in a week of big quakes, the (revised) M8.0 Solomon Islands quake held off triple coincidence for a mere 5h... check out this lovely recovery (... and subsequent, less-lovely aftershocks)

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

LIGO computing and network security (Roddy)
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Reported under General Computing, see below.

General computing and LDAS admin (Giardina)
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Reported under General Computing, see below

Reported under LDAS System Administration, see below

Data analysis & computing (Yakushin)
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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)

From: Rolf Bork rolf@ligo.caltech.edu

40m Lab

• DCPD: Ben is  finalizing the parts list for the DCPD PCB it will be stuffed soon. I am trying to figure out what to do about some American Capacitor parts.  They have a 3-week lead time, and a minimum order of 25 (at $28 each).  I only need four for this board, and I need them soon.  I'm trying to find an alternative.

AdL CDS Infrastructure

• Requirements and Conceptual design documents have been submitted. A review committee is being assembled for a CDR the week of April 23.

AdL SUS Noise Prototype

• The UK designs are progressing and the UIM coil driver board design will be sent out for manufacture on 4/13.
• Preliminary design of the noise prototype system and rack wiring is complete.
• Design of the whitening and interface boards will be started following OMC and Tip-Tilt.

OMC Suspension

• The system wiring diagram is complete.
• The modules and chassis we have on hand, ready to go are-- coil driver, sat amps, AA chassis, IO chassis, ADC interface, DAC interface, timing interface
• Still needed are-- SUS receiver, timing slave, AI chassis. The SUS receiver is being fab'd, AI chassis is waiting on the interface board which is being fab'd. The timing slave and a master has been requested from LHO. In the meantime, a software trigger mode for the system can be used for initial test and checkout.
• The ADC and DAC need to be ordered, but for the time being we can use modules from our test stand.
• Power supplies, rack, power distribution equipment and an operator station are needed for the room 56 setup. We may also need to extend the network into the room.
• A draft of the controls requirements document has been written and will be sent to Norna and others for review.
• Simulink model of the software should be done next week.

Tip-Tilt equipment for ANU

The equipment needed for ANU includes:

• 2 ea AA chassis- boards, parts and panels redesigned and on order
• 3 ea AI chassis- boards, parts and panels redesigned and on order
• 3 ea Sat Amp- boards and parts on order
• 2 ea SUS receiver- boards and parts on order
• 8 ch Coil Driver- boards stuffed, panels on order
• IO chassis components- boards and parts ordered for ADC adapter, DAC adapter, Timing Interface
• Components should be ready for shipment by 5/26 assuming no major procurement issues.

AdL PSL

• Beckhoff PLC equipment and software received. We also met with the Beckhoff engineers to try and determine the best way to interface to the AdL PSL control system. After meeting with us, they feel that their first suggestion may not be the best, or easiest option.

AdL ISI

• GS-13/L4C Emulation Module -One got stuffed, and needed some modification.  I cut another PCB, which arrived yesterday.  I will give the parts to the back shop for stuffing today.
• GS-13/L4C Control Module -  -One got stuffed, and tested O.K.  The front panels for both boards are in process at Front Panel Express.
• GS-13 Boards - I shipped off four complete boards.
• Coil Driver - (3 + 1) (Mohana) - Two Coil Driver chassis are complete, and look really good.  One is tested, and the other awaits testing, two more will be coming soon.
• STSTS-2 Control Module - One board is being tested now.
• S-2 Emulation Module - Mohana has finished testing this board.
• ADC Interface Rev6 - I have designed this board, sent it out for fab, sent out the front panels, and have received the parts.  I wait for everything to come back, so I can have them put together, and shipped.
• STS2 Breakout box - I have designed this board, sent it out for fab, sent out the front panels, and have received the parts.  I wait for everything to come back, so I can have them put together, and shipped.

See Advanced LIGO

40-Meter Interferometer (Weinstein)

IFO Commissioning, DC readout, Electronics, Controls, Computers

• Tobin continues to commission the new dither alignment system. He and Rana concluded that the two input PZT steering mirrors are so close together that they are nearly degenerate and only control one pair of angular degrees of freedom. They also determined that they need some kind of digital bandpass filter before the digital demodulators. Tobin will generate the appropriate code in Bork-space. Rana also suggested that the oplev readbacks be used to determine the sensing/control matrix.
• Rana found that the SDSEN damping of our suspended optics wasn't working because of some bug in the gain ramping: with the TRAMP field set to a non-zero value, the ramp time for the SDSEN gain becomes infinity (or close to it), so no change to the gain will work. He set TRAMP to 0 for all SDSEN damping loops and now they all seem to be damping better. He suggests that we systematically optimize the gains of all suspension damping loops, using Justin's newly-installed matlab hooks. A good SURF project!
• Rob is working on the dewhitening boards for all the test mass coil drivers. He's measuring the noise with dewhitening off & on and diagnosing bad opamps.
• Our main laser (MOPA) continues its slow recovery from the dramatic power loss of a few weeks ago. The power is now back up to 4.2 watts.
• Rana talked with Gregg Harry about optic charging and UV light discharging. They decided to hold off on any tests using 40m optics until the procedure is well tested elsewhere and deemed safe for the mirror coatings.
• Rana talked with Bill Kells about the scatterometer tests Bill was proposing. They agreed that the arm loss measurements already done by Tobin, as well as hi-resolution pics of the optics are all we need before venting to drag-wipe the test masses and repeat the measurements. This will determine whether the anomalous cavity loss is due to dust or coating imperfections. If it is the latter, Bill will proceed with scattering measurements. We plan to vent for drag-wiping in 3-4 weeks, depending on when Rob is finished with his next round of DC readout measurements.
• Tobin took a 9-sec exposure of the PMC with our new D40 digital SLR camera and determined that it sees 1064nm light as purple, with quite high resolution.

DC Detection

• Rob is gearing up for a series of measurements of noise couplings, comparing DC readout to RF. First up is laser intensity and frequency noise, and RF oscillator intensity and phase noise. Then loop noise couplings, angular (oplev) couplings, etc. He's developing ways to drive the various noise sources in a way that doesn't saturate them and gets good coherence, is calibratable in physical units, and is do-able from the control room.

Vacuum Squeezing

• Go and Osamu have been tuning up the squeezer to achieve more squeezing at lower frequencies.

Lab Infrastructure, Bake Lab

• Bob got a newfax/scanner/color-printer to replace the one that hasn't worked in months. Christian will set it up and send instructions on how to use it.
• Bob's bake lab is cooking on all burners, vacuum-prepping parts for LASTI.
• Trees along the x-arm roof were trimmed.
• A power transformer failed on Wednesday early morning, shutting down the AC. It will take 10-14 days to replace, so chilled water supply will be crippled. Expect the ifo lab to be warmer than usual.
• A noisy AC unit on the south annex roof has been fixed.

Thermal Noise Interferometer (Black)

LASTI (Ottaway)

• Efforts have been focused on wrap-up measurements on the HAM-SAS.

CIT Science Group (Weinstein)

Laboratory Computing (Anderson)

LDAS Software (Maros)

• The focus remains on the diskcacheAPI. Corrections for using the default memory mapped values for known file system types is currently being tested. Also under system testing are patches to prevent the lsync application from seg faulting on exit.
• Work continues on supporting list of lists within the cmonClient.
• LDAS was system tested using version 1.8.504 of the software. Except for lsync seg faulting at exit (the cache file it produced was correct), all system tests ran successfully.
• Some maintenance work of removing job output was done on ldas-cit to make more disk space available. Users were involved in the process to ensure no critical data loss.
• DB2 has been upgraded to the latest 8.2 fix pack (8.2.7) on LDAS-TEST.

LDAS System Administration (Anderson)

General Computing (Wallace)

Advanced LIGO and Supporting R&D (Shoemaker)

Advanced LIGO Systems

Modeling and Simulation

From: Hiroaki Yamamoto hiro@ligo.caltech.edu

e2e weekly meeting

Osamu explained the ITM and ETM mirror angular fluctuation and noises cause by those angular fluctuation. He explained details, emphasizing the importance of the whitening and dewhitening and windowing, when one is analyzing spectrum with string frequency dependence.

Sany Yoshida explained his strategy how to setup the coordinate systems, LAB - SEI - SUS and COC. He also discussed about the improvements of the length and frequency control of the advLIGO MC system he is working on.

AdvLIGO LSC/ASC design using FP arm model with quad suspension (Osamu)

As Rana's request, we are looking at the noise of angle motion of ITM and ETM during lock with low power. However we found that Matlab fft has a precision limit if the frequency slope is too steep. I applied a whitening filter on time series data and dewhitening filter on frequency domain data to recover high frequency tiny data. As a result of this process, the slopes reasonably matched predicted lines. Then we saw another limit by e2e and matlab numerical accuracy by using double precision,  but the noise level is already 1e-22 and it is low enough for the AdLIGO noise floor.

Scattering loss (Hiro)

There were some focused discussions on scattering losses, including John Stover of The Scatter Works and Chris Walsh of ARC Centre of Excellence for Ultra-high bandwidth Devices for Optical Systems (CUDOS). 

A very biased private summary is in www.ligo.caltech.edu/~hiro/advLIGO/scatteringHirosView.pdf. In the same directory, one can find a lecture about scattering given by John Stover on March 29th, BRDF_Basics_III.pdf (and .PPT).

One consensus coming out is that the CSIRO measurement of LIGO I mirrors by CSIRO was an underestimation of true roughness. 

They reported rms = 0.17nm for wavelength > 3.8cm^-1. This is based on their TOPO measurements. They subtracted tilt and curvature and calculated the RMS. This was needed because :

"Tilt is purely a measurement artefact associated with set up of the substrate and should always be removed. Curvature is part measurement artefact associated with the set up of the substrate and may be part the contribution of a surface feature whose wavelength is considerably larger than the measurement aperture. In either case, removal of curvature is also justified. To repeat: these terms must be removed because they are not real." (excerpt from Chris Walsh e-mail on April 4)

Still this process to discard "not real" artifact introduces some bias to make the "measured" rms to be smaller. This was demonstrated by generating data with similar spectrum as the micro roughness. The rms after subtracting tilt and curvature component was a half of the value of rms calculated without the subtraction.  This makes the estimated loss to be 21ppm, instead of 5ppm.

This rms or loss was calculated in another way. CSIRO wrote a paper analyzing the LIGO I mirror (Appl.Opt. 38 4790-4801 (1999)). They show PSDs of three measurements covering difference frequency regions. TOPO measurements with different magnifications show the artifact mentioned above. These three data sets can be fit by a smooth line in the region about 1cm-1. Using this smooth line, the rms above 3.8cm-1 was calculated to get about twice as large rms than they reported.

So, the RMS of micro roughness is WORSE than we expected. The larger angle BRDF (4.4 10^-8 / theta^-2.45)  is slightly better than original estimation (10^-6 / theta^2), but not as good as is estimated in T060013 (5e-13/ theta^3.6).

The total loss per LIGO I mirror has been estimated to be ~70ppm based on several measurements, including visibility, large angle measurement by Bill K, power recycling gain, etc. Out of this 70ppm, 20-30ppm could be explained by the loss due to the surface figure and others and 30-50ppm was unknown loss. Now the micro roughness measurement could explain 15-25ppm out of these losses "unaccounted for" hitherto.

Some 10-20ppm loss can be attributed to the spotty large angle scattering losses. 

The FFT will be refined so that the loss in the region between 1mm ~ 5mm will be reexamined to quantify the loss in this region more carefully.

The requirement of the micro roughness for the advanced LIGO mirror will need to be reevaluated so that the roughness is consistent with our requirement based on the loss budget.

Modeler - e2e simulation engine (Hiro, Bruce, Melody)

Bruce and Melody worked to implement and refine the interface to support the User Defined Primitive modules, including parsing, editing and loading .udp files in Alfi and parsing in modeler.

Bruce kept working on the integration of the udp support in modeler.

Mechanical Simulation for advanced LIGO (Sany and SLU team)

Found an error in the coordinate transformation from the HAM table to the triple suspension in our e2e modeling of AdvLIGO Input Mode Cleaner (the triple suspension model developed by Mark Barton uses a different coordinate system from the single suspension e2e model used for Initial LIGO). Consequently, in the previous computation with the correct orientations of MC1 and MC3 (about 45 deg off the X-arm direction), the suspension point motions sent to these optics were lower than what they ought to be. Fixed the problem and repeated the computation to find that the dc gains for the frequency and length sensing controls needed to be increased to lock the cavity. Will continue the computation to optimize these gain settings.

CDS

Prestabilized Laser

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

Assembly of the lab prototype 35-W laser is near completion.  A problem with the 2-W NPRO noise eater was fixed when the circuit board was replaced by InnoLight.  Alignment of the optical train was completed and mode matched to the amplifier.  The output power of the laboratory prototype was 36.7 W with a nice beam - as it appeared on a camera; it hasn't been characterised by the diagnostic breadboard as yet.  The transfer function of the high-bandwidth current modulation input was measured.  The shape of the magnitude response changed with increasing the source amplitude and exhibited a resonance around 20 kHz.  Whilst it is not planned to use this actuator for the intensity stabilisation, it was interesting to note.

I also saw the diode box / power supply assembly for the 35-W laser.  One problem might be that when the diodes are energized, the noise from the power supply fans increases a great deal. Replacement fans for the OEM power supplies have been ordered. A minor problem with the software interface was fixed.

I suggested to Christian that the interface should be more obvious to indicate when the laser is on.  The current button animation combined with wearing laser safety eyewear tended to make it hard to tell. 

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