Weekly Report for Week Ending December 20, 2001


 Exec. Comm. Agenda
Highlights
LSC
Administration
Hanford Observatory
Livingston Observatory
MIT
Caltech
Detector
40 Meter
TNI
LASTI
Data Analysis
LIGO II/Adv. R&D
Past Weekly Reports

The LIGO Executive Committee Agenda for Monday  December 24, 2001 will be:

 CANCELLED DUE TO HOLIDAY AND NO MEETING ON DECEMBER 31

THERE WILL BE NO WEEKLY REPORT NEXT WEEK.
 

Special Items:


Special Announcements:

Our colleagues in Virgo passed a major milestone. In an email to Virgo members, Project Leader Adalberto Giazotto wrote:

"Dear colleagues,

We have the Virgo Christmass present: today 19/12/2001, at 12:10, the
recycling mirror has been locked  for 45 minutes  with a recycling gain
of 100, pushing with coils . This means that the recycling mirror (20 kg)
has been locked in a physical space of about 4nm and that the whole central
interferometer has been locked.  This fantastic achievement shows once
more that our team and  our system are simply great.

Happy xmass
                                             Adalberto"
 
 


Weekly Report Highlights
 


LSC Issues (Weiss)


no report


LIGO I Construction/LIGO Laboratory Administration (Lindquist)



 

LIGO Operations--Administration



LIGO Weekly Site Telecon (Lindquist)

A Site Teleconference was held on Thursday, December 20, 2001.  Discussion centered on the status FY 2002 costs-to-date, of NSF funding, and the establishment of FY 2002 accounts, as well as the status of building at the two sites.

The list of current actions revised to reflect the status of open actions assigned through December 20, 2001 may be found at ACTION LIST.


PROPERTY MANAGEMENT (Chargois)

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


DOCUMENT CONTROL CENTER (Turner, Mak)

>From: Linda Turner - turner@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

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

ACTIVITY


COST SCHEDULE CONTROL SYSTEMS (Cunningham, Brambila, Kaufman, Akutagawa)

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

Press here for ACCOUNTS PAYABLE HISTORY DATA.

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

From: Florence Kaufman <fkaufman@ligo.caltech.edu>

SUBCONTRACTS MANAGEMENT (Petrac, Jasnow)

From: irena@ligo.caltech.edu (Irena Petrac)

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

CONSTRUCTION:

OPERATIONS:

SUPPORT

 
Irene Baldon Dorothy Lloyd Rita Torres

Advanced LIGO (Frey)

From: Thomas Frey <tfrey@ligo.caltech.edu>

Progress Period from 12.14 to 12.20

Accomplishments:

Schedule 12.21 to 01.03:

Reports (Lindquist)

We are doing a standard Annual Report for the Construction Project as of the end of November.  I have requested contributions from Task Managers by Friday, December 21, 2001.



Change Control/Contingency (Lindquist)

The following change request has been submitted:
 

CR-010012
Revision B
WBS 1.4.4.1 Closeout Construction Budgets for Initial Computer Equipment Complement at the Sites (Larry Wallace will argue for spending these funds on network connections) P. Lindquist

Press for the latest Contingency Needs Projection.


Human Resources (Akutagawa)

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


Quality/Safety (Tyler)

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

Conducted a safety audit of the 40-m facility. The audit team consisted of Sanders, Scislowicz, Issaian, and Tyler with Vass, Weinstein and Ugolini as "guides".  A report is in work and a draft will be distributed within the next two weeks (holidays permitting).  The way that the laser safety interlock system was being operated was questioned with regard to providing sufficient personnel laser protection.  This will be reviewed and the operation/system revised as necessary to assure the existence of two "levels" of protection at all times.

Received the cost estimate from Physical Plant for addition of a fire suppression system to room 215 Synchrotron.  A different type of fire suppression gas is being proposed rather than the FM-200 system installed at the observatories. One of the claimed benefits for this system is fewer and less costly modifications are required to "seal" the room.  Further review and discussion of the proposed approach is in work.
 


LIGO Hanford Observatory (LHO) Operations (Raab)


---------------------
Facilities
---------------------
OSB EAST
Stem walls and footers are 90% complete. All underground plumbing is being
hydro tested. The fire water line is cut in to the existing line. The
electrical main feed and the communications lines were started this week.
The contractor is on schedule and we also allowed them to work during the
E-7 run.


LIGO Livingston Observatory (LLO) Operations (Coles)


Detector: Optics and Installation: Had to relocate two legs of the PSL Laser Safety Enclosure to accommodate the soon to be installed Acoustic enclosure. Designed and fabricated a fixture for Peter King to optically contact surfaces on new PMC bodies. Received and partially uncrated the PSL Acoustic enclosure. The vendor, Acoustic Systems in Austin, Texas delivered overnight a beautifully packaged assembly. 12,000 pounds of the nicest packaging I think we've ever received at LLO. Assembly and erection will commence immediately following E-7, on Jan 15. Worked with Gabi, and ordered an assortment of long f.l lenses to try in the Guoy Phase telescope. Programming of the Laser Safety Interlock system has stopped for the week; the contractor has his installer on another job. (Jonathan Kern)

PEM: All dust monitors are now operational except for the 3 needed for vacuum purge. All 3 site weather stations are now operational after service to the data loggers. (Rich Riesen)

Interferometer: We are updating the ISC table documentation to reflect the as-built changes to the layout that have occurred during the commissioning effort. This is continuing as a background task for operators on shift.

Preparations for E7: Next week's control room schedule is now posted. IFO locking procedures are now incorporated in dialog boxes on the medm screens plus paper prints available in the control room. The feed forward system can now be found on the medm screen under MSC with on-board operating instructions. We are revising the operator check list and will have the updated version on-line before E7. Rich Riesen

LDAS: worked some issues with the beowulf nodes and networking configurations. Some of the nodes were not responding. There may still be some issues with them.

GC: working on a web page for several people here where they can post  data files that they would like to archive. We have ordered a DVD writer for testing. There is a growing need for people to be able to move large data files to their laptops, etc., and we hope this will be a solution.We are continuing to prepare for the E7 run. (Tom Evans, Shannon Roddy)


Detector/Technical Support (Whitcomb, Coyne)


 
Installation& Commissioning:
Hanford
Livingston
Other Science/EngineeringActivities:
Design/Analysis/Fab
Issues/Concerns
See also the Installation web page

This week's report covers two weeks of work since someone screwed up last week and forgot to send in the detector section....

1.1 LHO INSTALLATION & COMMISSIONING

2km Commissioning

Nergis and Stan reporting:
This week has been spent we've been whittling away at the noise, concentrating primarily of frequency noise due to mode cleaner displacement noise. We found two very large noise sources: coil driver noise on MC1 and MC3 (they were oscillating at ~50 kHz causing a huge 1e-6 V/rtHz noise at ~100 Hz, consistent with frequency noise seen in the arm cavity spectrum); and radiation pressure driven displacement noise in the MC (the unservoed relative intensity noise was measured to be 5e-6 1/rtHz). "Snubber" circuits are installed to eliminate the  coil driver oscillations so that the coil driver monitor outputs are at the level of 50 to 100 nV/rtHz, still high compared to the expected 20 nV/rtHz. Further investigations are ongoing to reduce this noise and some sharp lines as well. The intensity stabilization servo was revived, though with lower gain than before such that relative intensity noise into the MC is 2e-7 1/rtHz. These improvements gave a  modest factor of 3 to 4 reduction in the arm cavity noise between 20 and 700 Hz.

Some efforts are ongoing to understand the difficulties in locking the interferometer in power-recycled mode, though no obvious cause for the degraded locking behavior has yet been identified.

We have continued to work on understanding why the interferometer locks well at some times and not at others, even when the alignment and other conditions seem  to be comparable.  The immediate cause seems to be a proclivity at time to show bursts of ~12 Hz noise in the Michelson sensors.  These burst drive the real Michelson and cause the differential arm length to be driven to compensate.  None of the obvious sources of potential burst seem to be the culprit.  We have been tuning some of the filters to see if we can improve our situation.

With eveything working well, the noise level is in the high 10^-17 m/rtHz range between about 400 and 2000 Hz.

4 km Commissioning

Nergis and Stan reporting:
The mysterious clipping of the input beam on the Faraday isolator reported last week has been corrected by a major realignment if the input optics; the cause of the clipping is still not known. The 4k ifo was then set up to run in recombined mode. To this end, light levels at the reflection and antisymmetric ports were increased (by removal of attenuators), the lock acquisition parameters were measured (and hand-tweaked) and the 4k ifo now locks easily and reliably in recombined mode. A first look at the differential mode noise showed a very high level: 8e-13 m/rtHz  at 100 Hz and 1e-14 m/rtHz at 1 kHz.

The new digital suspension code for the large optics in the LVEA has been installed and tested.  It has the correct digital filters to compensate for the filtering in the coil drivers, as well as the capability (not yet implemented) to use a the frequecny dependent output matrix.  The digital filters temporari;y installed in the LSC code to compensate for the coil drivers have been removed.  This required some gain reallocation to avoid clipping.

The major source of noise was identified as frequency noise due to DAC noise driving the modecleaner length.  The digital suspensions have a low pass filter on the outputs to eliminate this noise, but it cannot be engaged on the MC optic which is driven to lock the modecleaner without lowering the gain in that path too much for the interferometer to lock.  The for this optic have been modified (moved to a higher frequency), and will be tested to see if they can be engaged and still achieve stable locks.  If so it should lower the frequency nois e by about a factor of 30 at 100 Hz.

1.2LLO INSTALLATION & COMMISSIONING

4 km Commissioning

Rai Weiss reporting
The major efforts continue to be reduction in the noise and improvement in the duty cycle.

NOISE
The noise in the 200 to 2000 Hz band has been brought down to 10^-16 m/sqrt(Hz) which corresponds to 3 x 10^-20 strain/sqrt(Hz). The improvement is due to changing operating conditions: reducing the gain in the optical lever damping loops and reducing the gain in the mode cleaner mirror servo, thereby lowering the cross over frequency between mode cleaner and reference cavity frequency control. The change in operating conditions sacrifices robustness for sensitivity improvement and is not a universal solution for Livingston. The primary contributors to the current level of the noise are:

* high frequency (f > 50Hz) noise from the optical lever damping loops due to insufficient signal and inadequate filtering. New digital filters for the optical lever damping loops are being designed.

* D/A glitches arising from the switching in the converters at negative slope zero voltage transitions. The level and spectrum of this noise is under theoretical and experimental investigation. Replacement of D/A converters with newer and lower glitch amplitude versions has not immediately caused a reduction in the noise. However, it is clear that once other known noise terms have been reduced this noise will dominate.

* Elimination of oscillations and excess noise in the mode cleaner mass controllers. The noise source has been detected at both Hanford and Livingston and has been reduced at both sites.

Other on going noise investigations:

*  Measurement of the noise in the signal chain of each of the large optic masses. The noise may not be the same in all.

*  A careful set of measurements of the Q in the pendulum and internal body modes of the large optics. Gaby Gonzalez has assembled a useful atlas of the relevant formulae and Q values.

DUTY CYCLE
As reported last week the duty cycle for operation of the recombined interferometer can be as high as 0.6 while the duty cycle for operating a single long arm cavity is close to 1.0. Early morning runs were made to record the transients in the interferometer signals just prior to lock loss from increased seismic noise of the day. It appears that angular motions of the long arm cavity optic axes are still responsible for the lock breakdown. During the past week the quadrant diodes at the transmitted ports of the cavities were fully instrumented and were used to measure transverse beam motions. The indications are that the optic axes are pivoting about the etm.

Other on going work to improve robustness:

*  Improvements are being made in the temperature stabilization of the laser reference cavity to reduce the common mode excursions of the interferometer
Peter King has been trying to understand the workings of the Minco process controller, in order to get a better handle on the parameters used in the  regulation of the reference cavity temperature.

*  A method to impress signals on the fine actuators at the end stations to reduce the tidally induced motions by "hand" or by servo is being studied.

Continue the preparations for E7 to improve robustness and sensitivity

Sensitivity
The sensitivity remains at 3 x 10^-20 strain/sqrt(Hz) between 200 to 2000 Hz when operating with high sensitivity settings. The noise above 200 Hz may still be dominated by the D/A and we are attempting to increase the digital signal levels followed by more aggressive analog low pass filters. All other efforts to improve the noise will wait until after the E7 run.

Robustness and improved operating procedures
The operating parameters for the interferometer and procedures for bringing the system into lock have been documented on the individual subsystem screens. Information is provided for robust and high sensitivity operating modes. During E7 the decision on the operating mode will be made by the operator in consultation with the on duty scientist. The criterion for shifting from one mode to the other is primarily the seismic noise. Currently, when the seismic noise velocities lie below 0.3 microns/sec in the 1 to 3 Hz band at the end stations and the central building, it is safe to shift to high sensitivity mode. These conditions apply most nights.

There has been some success in operating the interferometer in robust mode through the day. In fact, the interferometer lock survived the train when carefully aligned and with all optical lever damping gains at maximum (just below the onset of oscillation) and the mode cleaner servo gain set high. The best guess for the cause of the break down in the recombined interferometer locking is still a differential angular motion of the two cavity beams which destroys the interference. Work is ongoing to improve the differential mode wavefront sensor and use it in a servo loop to maintain the fringe contrast. The problem with this system has been poor separation of the angular motions of the ITM from the ETM. An optical design iteration is being made with as built measurements of the antisymmetric port Gaussian spot radius and wavefront curvature. We do not have the time before E7 to implement the control loop but could bring it into operation if the loss in duty cycle due to excess seismic noise during the E7 run merits it.

A servo to adjust the temperature of the laser reference cavity to null the "DC" common mode arm signal has been installed by Peter King. The loop seems to be working but will need more adjustment before we can use it reliably in E7.

Peter King
I have been looking at the trend data relating LSC-CARM_CTRL and PSL-FSS_RCTEMP to see the relation between them and the PSL-FSS_TIDALSET signal.  During one evening run, the sign and response to PSL-FSS_TIDALSET was noted.  The next morning the LSC-CARM_CTRL signal was kept between +/- 8000 counts by manual adjustment of the reference cavity temperature.  An EPICS sequencer has been written to mimic the "human servo".  The sequencer was test last night and the software gains and settings still need some tweaking but it does work.  This morning the sequencer had a hard time trying to hold the LSC-CARM_CTRL signal whilst some construction work was being done at the Y End.
 

2.0 OtherEngineering and Scientific Activities

2.1 Design/Analysis/Fab

Modeling

Erika D'Ambrosio
I finished a formal demonstration for the two dimensional case that shows the perturbations which keep balance of the sidebands are only I have been knowing that for simulations results and inspection of the matrix elements. Using the formalism of the SU(2) group I was able to prove that those conditions are the necessary and the sufficient ones. I achieved a complete proof using the SU(2) formalism and I am trying to extend this in more dimensions.

Also this doesn't depend on a common phase; this has puzzled Bill and me for a long time since it was not clear if adjusting the carrier would give a better balance. Other things I was lucky to understand using the compact formalism of SU(2) are the relations between the eigenvalues and the eigenvectors. I learnt that the scalar product established by the eigenvectors for the two sidebands guarantees the balance when the cavity is driven by a laser beam in the cases mentioned above. This was not trivial since the basis is not orthogonal and it gives cross terms that in principle could be an additional cause of imbalance.

I have read some literature on the detection scheme to understand the consequences for it.

Bill Kells

Core Optics

GariLynnBillingsley
Data posting for all COCs installed in vacuum is complete and available at
http://www.ligo.caltech.edu/~gari/COCAsBuilt.htm  please contact GariLynn X2184 if you have any questions.

Bill Kells

Lee Cardenas
OTF - CIT
Efforts to lock the cavity in the Contamination chamber are in progress.
The other Contamination chamber it is being gradually putting the optics together.
The Contamination Chamber.  As I mentioned to you,  the laser is resonating in the cavity and signal is detected on the photo diode detector.  The laser power coming into the ref. cavity is only 30 milliwatts, the paper on this subject mention the power to be 100 milliwatts , so I need to bring more power and optimize the signal power on the TEMoo  mode. all these efforts will continue on.

OPTICAL LEVER ANGLE SENSOR

Mike Smith, Ken Mailand
A design for a fixed, 50m focal length objective lens has been developed and the packaging design is being finalized by Ken Mailand using Solidworks. It appears that the optical lever receiver box will use the same mounting bracket and be 2.5 inches longer (on the end opposite the input port; total length 19.5 in) than the present LIGO design to accomodate the lens.

A zoom lens version has also been developed, which uses the same back-end magnifier portion of the optical system with a commercial motorized zoom lens being substituted for the fixed objective portion. The lens will fit inside the new 19.5 in box, provided the optical port can be moved 1.6 in closer to the end of the box.

The packaging design for the 50m focal length objective lens is being finalized by Ken Mailand using Solidworks.

PSL

Peter King
The output of NPRO #259 was circularized.  Previous measurements obtained with the BeamScan were not repeatable because of some distortion introduced by the reflective neutral density used.  The output ellipticity was improved from 1.23 to 1.06, on average.

Jonathan Kern made a nice little fixture to assist in positioning a 1 in. diameter mirror on the pre-modecleaner body, prior to the optic being optically contacted.  The half a dozen or so attempts to contact the mirror to the prism have not been successful.

Lee Cardenas

LASTI-MIT
I have completed the installation of the HI-Power laser and the power optimized to be 11.00 watts.
The Ref. cavity assembled, aligned and set in place as well.
I helped them organized half of the optic lab. before I left MIT.
PSL-CIT
Re-Organized the lab, bake chamber to be opened and items to be shipped to LLO in progress.

D. Ugolini as well as P. King mention to me that the 10 watt laser power is down to 6 watts.  Ugolini claims that the drop is due to the NPRO power that went down to 200 milliwatts.  The NPRO output power should be at least 500 milliwatts before it gets to the amplifier.  I have looked the laser at the 40m lab.  But, there was no body in the lab.  So I will check the power of the NPRO tomorrow to verify if it is due to the NPRO.

Rick Karwoski
PSL FSS Spares --I re-tested and delivered one frequency stabilization servo for LLO. In the process I discovered one of the 15 volt regulators oscillating. This is the third such incident in as many weeks.  All regulators on the board now have beefed up filtering which stops the oscillation.  A second unit slated as a spare for LASTI has been 2/3 tested. It should ship in the next day or two.
ISS Activities -- I completed testing on the digitally controlled frequency shelving network.  This circuitry is a converted version of the analog controlled compensation network in the ISS prototype currently at LHO and LLO.  It is slated for the VME/EPICs-controlled  version of the ISS.
This week I completed testing on a spare Frequency Stabilization Servo for LASTI.  It was shipped.  Latest DCNs were incorporated on the board. The GEO FSS is currently in test.

Four photo detector spares slated for LHO and LLO are undergoing a final review.  GAP diodes have been replaced with EG&G standards in two units. Our objective is to get all four to Hanford for the formal ATP in the next day or two.

40 m Bake Chamber

Lee Cardenas
I just finished working on the big vacuum bake oven.
I had to change the oil on the roughing pump three times before it can be operated.
The old oil it was very dirty, it had lumps of rust particles.  After the oil change, It looks OK?
But it needs more cleaning.  I will coordinate with Bob Taylor to have all the pumps the oil changed.
Yesterday, Bob and I finished the plumbing of the chamber.  We found most of the o-rings were cracked so
we replaced them all.
I have turn the pump on and started to evacuate the big chamber but the pressure couldn't get lower than 700 torrs so the turbo pump couldn't turn on.  I closed the valve by the chamber and pressure quickly drops to 5E-3 torrs.
It seems that the chamber leaks. I noticed that the chamber door has a gap of about 1/16 inches at 6 o'clock.
I think this door is warped as you mentioned to me.  I think this is the chamber that it is not good.
The other chamber which sits on the floor the door is nicely closed all around it.  I will check the door of the bake oven in question tomorrow.  Right now, the pump is on and it is pumping up to the chamber valve.

CDS/DAQ

Rolf Bork
Getting second framebuilder built up at LLO. We want to use this one to check if present LLO framebuilder (writing 1 sec frames) is experiencing same problem as found at LHO. Since problem appears to be load dependent, LLO unit may be ok (not as heavily loaded as LHO).  If so, we won't upgrade it until after E7, per Rai's request.

In any case, we want to set up the second LLO framebuilder same as LHO and test it for the upcoming E7 run. The frames written by second FB would then be same format/size as LHO and LDAS could then grab these frames, if so desired. In this way, we may be able to satisfy both Rai's request for no change to the main system and Albert's request that frames be the same at both sites.

If present framebuilder is found to have problems, we will request that it gets the LHO upgrades as well. Upgrading the present unit will require more changes, as dataviewer and DTT will have to be upgraded and more memory will be required to be installed in the framebuilder.

Lori and Hongyu have begun testing of multi-cpu Epics Data Collection Unit (EDCU).  There is no plan to install this before E7.

Lori and Hongyu still working on multi CPU EPICS data collection.

Calibration

Luca Matone
Michael Landry and myself have been working on an automated calibration procedure. This procedure was tested on the 4k and yielded calibration results consistent with the normal 'counting of fringes' procedure.

The idea is to lock a simple Michelson and change the sign of the control loop after an arbitrary amount of time (presently this is set to 5 s). The change of sign forces the system to transition from bright to dark fringe (or vice-versa). Close inspection of the transitions show a consistent lambda/4 transition. This procedure has not only the potential to be automated but it gives the possibility to yield precise calibrations.

We also 'counted fringes' on an asymmetric simple Michelson: ITMx and ETMy. Although we have obtained consistent values for the ETMY calibration, the ETMx calibrations is off. We plan to apply the automated calibration procedure to the asymmetric Michelson in the future.

Digital Suspension Controls

Jay Heefner
  • Schematics for the SOS pole/zero module and the revised SOS coil driver have been circulated for comments. Board layout should begin next week.
  • The DSC Pole/Zero module layout will be complete by 12/20. It will be sent out for fab and should be ready by the first week of Jan.
  • The schematics for Rev B of the SOS Coil Driver are complete and board layout will begin next week.

  •  
    Rolf Bork
    Finished the digital suspension software changes for the LHO4k LVEA large optics; testing started this week.  I still need to make the changes to the end station code.

    Code finished for LHO4k lvea and appears to be functioning properly at LHO.

    New code finished for end stations; should finish testing tomorrow and send up to LHO.

    Luca Matone
    The two main developments for this week are the testing of the Output Matrix filters and the first implementation of Rolf's new DSC code.

    Last week we went through the DSC system in order to characterize its filtering properties and get familiar with the controller. We then moved onto implementing a series of digital filters, referred to as Output Matrix filters, whose scope is to reduce the cross-coupling between the mirror drive along the beam axis and its pitch (presently, the 3 IFOs have a DC compensation to reduce this coupling; the filters being tested would provide a reduction at all frequencies). The idea is described in T01040-00-D by P.Fritschel.

    The idea behind the filtering is simple:

    The exact shape of the filters is provided by solving the equations of motion of the mirror. It turns out that the soultion is an unstable filter and a damping term (Q=1000) was introduced to make it realizable.

    The next step was to load the filter in the DSC system, damp the mass (we worked on ITMY) and measure the cross-coupling. It turns out that damping loop became unstable once the digital filter was enabled. This was observed on the optical lever signals a couple of minutes after it was enabled. The masses began to oscillate at 750mHz and its harmonics and we presently don't understand why the system should ring (the pendulum Q>>1000 is damped by the local controller, why shouldn't the Q of the filter?)

    We decreased the filter Q from 1000 to 10. We ran a simulink model to verify that the changed filter would still reduce the cross-coupling term, although not as much as the original solution. According to the simulation, the reduction, with respect to the DC compensation, would be ~20dB at 100mHz and >60dB above 1Hz.

    We loaded the filter in the DSC system, and we damped the mass with the filters enabled: no oscillations were observed and the system was stable. To measure the cross-coupling term, we excited ITMY along the beam axis (H1:LSC-ITMY_EXC) and we monitored the optical lever signals (H1:SUS-ITMY_OPLEV_PERROR) in pitch. We took a TF of these signals from 10Hz down to 100mHz in different conditions: no compensation, the current DC compensation and frequency dependent compensation. At 100mHz, the cross-coupling term with the filters enabled was ~20dB higher with respect to the DC compensation. On the other hand, at 2Hz the filters were able to reduce the coupling by ~10dB with respect to the DC compensation.

    The work ahead: need to verify that the coil asymmetries have been taken into account; need to implement the T2P filter (torque-to-position compensation); need to explore filters with a higher quality factor (Q=100).

    Just recently, we applied some modifications to the DSC filter coefficient files and ran Rolf's new DSC code. As far as the local controllers, the mirrors are damping, however we need to test the LSC section of the code.

    LSC

    Jay Heefner Rich Abbott Peter Fritschel
    Completed revisions to the manuscript 'Lock acquisition of a gravitational wave interferometer', and re-submitted it to Optics Letters. The various revisions were based on reviewer suggestions (& demands!), and on the need to shorten the manuscript to fit the page limit. Hopefully it's even an improved paper. The re-submitted version has been sent to the dcc as P010015-04.pdf.

    Rolf Bork
    Added violin mode stopband filters for LHO2k ETMX/ETMY.  Sigg will test at LHO.

    Looking into problem reported from LLO that they can't get a second digital dewhite compensation filter to function.  This second filter is required to compensate for the second hardware stage that was added.

    EO Shutter Controller

    Sander Liu
    Wrote draft of Acceptance Test Procedure for the EO Shutter Controller (LIGO-T-010154-00-C). Document will be released soon.
    Refurbished returned controllers, S/N 001 from LHO and S/N 005 from LLO. They are under test now.
    Received two new high voltage pulsers from DEI.Shipped one to LHO and one to LLO

    Antialiasing Filter Chassis

    Sander Liu
    In the process of getting quotes and buying parts for 10 additional LEMO version units.

    Data Monitoring Tool

    John Zweizig
    This week I continued to fix bugs found in the DMT software. I have also started to install new and modified monitors for E7 and to get the software installed on decatur, fortress and lancelot updated to be compatible with the current DMT version.

    This week I continued to prepare the DMT software for the E7 run. Serveral errors were found and fixed in process managment, and the name service. I also added a new compound filter class that can be used to pass a time series through several filters, one after the other. the first use of this will be in a monitor for testing different transient detection algorithms.
     
     


    40 Meter Interferometer (Weinstein)



     



    Thermal Noise Interferometer (Libbrecht)


    no report


    LASTI (Zucker)


    no report


    Data Analysis and Computing (Lazzarini)


    Simulation and Modeling (Bhawal)

    LSC characterization
    ------------------------
    (Luca) I have used the lock acquisition model (Han2k) and verified that the
    de-modulation RF phases for the photodiodes is optimized. I plan to modify
    the present reflectivities set for the mirrors and create a symmetrical IFO
    for simplification. The RF phase tuning may have to be re-done.

    Hiro and I have been comparing the LSC Matlab model built after a series of
    measurements and its e2e equivalent. We found discrepenacies in phase above
    1kHz that we are trying to resolve. Our goal is to produce the TF of
    the recombined and recycled IFO frequency response for E7.

    Lock acquisition in presence of mode mismatch
    -----------------------------------------------
    (Biplab & Hiro) The lock-acquisition procedure could be extended to more level of
    mismatch present but found that after certain level, it's not robust enough.
    Changed the code to include a phase factor (orginating from mismatch but suppressed
    in code for good reason) so that all locked cases can be analysed in same coordinate
    frame.

    Sideband mismatch in recycling cavity
    --------------------------------------
    (Biplab) studied effects of misalignments in various mirrors of the recycling cavity
    on relative differences between sidebands. Observed some such differences originating
    from these effects. Discussed with Bill Kells.

    Physics/Code diagnosis
    -------------------------
    (Hiro) Working to diagnose two issues reported by Bill Butler (psd calculation
    for a wide dynamic range) and by Luca Matone (digital filter at high
    frequency end and the difference between analog and digital simulation).

    Alfi
    ----
    (Bruce)
    - Completed edit window updates.
    - Working on Alfi file writing.

    (Melody)
    - Continuing on the alfi5 implementation. Working on the node user modifications.

    LIGO Data Analysis System

    Software Systems (Blackburn)

    The long awaited release of LDAS (0.0.23) for the E7 engineering
    run has finally been released. It was pushed from Caltech to the
    MIT, LLO, and LHO systems last night. This marked the end of two
    weeks of intense testing and debugging of the system. While there
    are known issues remaining, all involved in the preparation feel
    that this is one of the more stable releases of LDAS and ready for
    a tough two and a half weeks of usage during the run. Some of the
    remaining issues are

    a) dlmalloc not used on the Sun platforms
    b) version of dlmalloc used on Linux platforms not entirely
       thread safe
    c) about 0.1% of the jobs at the sites will fail in the
       dataconditionAPI due to a bug which was only today understood.
    d) the development system of LDAS is much less stable than the
       site systems, it is not known if this is software or hardware.
    e) the resample code in the frameAPI is too unstable to use by
       anyone other than experts and needs to be unified with the
       code in the dataConditionAPI.
    f) the diskCacheAPI functionality still remains in the frameAPI
       as there was insufficient time to make the break in the code
       implementation and still be ready for the engineering run.

    New ldas access accounts were set up for the LSC for the E7 run.
    There is one new account per search code shared object to be run
    during the run on-line. These accounts are now available and the
    LSC leads for the shared objects have been contacted with the
    necessary information.

    LDAS was tested during this past week with an un-tagged and un-
    official version of LAL and LALwrapper. There will be a pre-
    release of LAL and LALwrapper tagged tomorrow which we will be
    placing on all LDAS system for the upper limits groups to use
    in their preliminary code characterization studies over the
    weekend.

    Hardware Systems (Anderson)

    Caltech
    -------
    (Dan Kozak)

    Reconfigured the physical and power installation of the Sunfire 880 and
    associated racks in Booth.  Installed the video card in the Sunfire
    880 and ran diagnostics.

    Tested patch to FC Switch software on the test system;it worked and was
    subsequently installed at LHO.

    Installed QFS and QFS licenses on LLO dataserver, metaserver and FB2.
    Configured filesystem shared between fb2 and dataserver.  Still waiting
    on word from Shannon as to the fate of the data/exports on T3-1 & T3-2
    before setting up the big data cache (all config files are in place).

    Continued (at somewhat lower priority) migration of data from IBM 3590
    and Redwood tapes to 9940 tapes.

    Brought HPSS back up after CACR network changes brought it down.

    (Al Wilson)

    The box known as tester or gwave-75 is now known as corona and has a
    static ip. It will be used for testing system configurations. I am now
    testing it with RH7.2 alpha builds. (rpmsync and cfdef) I am also
    switching laptops. My old one died.

    (Stuart Anderson)

    * Code maintenance on cfdef system installation script for Solaris.
    * Solved a problem related to archiving the 16-sec trend frames from LHO.
    * Coordinating activities to ensure that LDAS will be able to analyze
      and archive valid 16-sec frames at LLO for E7.

    MIT
    ---
    (Keith Bayer)

    ran mirror script to update admin node
    installed greg's T3 date sync script
    ordered 25pin <-> 9pin modem cable for SF880 to trap diagnostics
    cron'd script measuring network speed to/from Caltech for data gathering

    Livingston
    ----------
    (Shannon Roddy)

    worked some issues with the beowulf nodes and networking
    configurations.  Some of the nodes were not responding.  There may still
    be some issues with them.

    (Igor Yakushin)

    * Installed fiber card into dataserver;
    * Connected dataserver with T3 with fiber wire;
    * Got a new computer but could not configure it so far:
          at first glance there seems to be some hardware problems
         (perhaps, a broken hard drive);
    * Learnt Tcl (first 221 pages of Welch's book);
    * Read documentation about QFS.

    Hanford
    -------
    (Greg Mendell)

    1) Backed up a portion of E6. (The remainder is available from HPSS at
    Caltech.)

    E6 data preserved at the sites:

    At LLO:

    690000804 - 690008003 (Nov 16, 2001  20:53:11 CST - Nov 16, 2001
    22:53:10 CST)
    690159204 - 690162803 (Nov 18, 2001  16:53:11 CST - Nov 18, 2001
    17:53:10 CST)

    At LHO:

    689999120 - 690009904 (Nov 16, 2001  18:25:07 PST - Nov 16, 2001
    21:24:51 PST)
    690158576 - 690162160 (Nov 18, 2001  14:42:43 PST - Nov 18, 2001
    15:42:27 PST)

    This data will remain on disk until at least E7. These times mostly
    overlap, and include the 2 hour stretch that Peter injected inspiral
    chirps into the LLO detector: 690001000 - 690007300.

    2) Received from Sun the remaining items in the Sun Fire 880 order.

    3) Installed another fiber channel card in ldas dataserver.  Patched a
    bug in the switch manager gui, and configured zones to all used of 16
    T3s to archive LHO E7 data.

    4) Set up a QFS files system at LHO to archive E7 data.

    5) Upgraded the tapecontrol script to archive E7 data.  During E7 we
    will do archive E7 onto T3 disks and onto tape simultaneously.  Tests of
    this configuration have run successfully for two nights.  We are ready
    to archive the E7 data at LHO.

    Documentation for the tapecontrol script for E7 will be at this URL:

    http://apex.ligo-wa.caltech.edu/~gmendell/tapecontrol/tapecontroldoc.html

    Log files during the run will be at these URLS:

    tapecontrol log for LHO backup to T3s:
    http://www.ldas.ligo-wa.caltech.edu/ldas_outgoing/tapecontrol/logs/log.html

    tapecontrol log for LHO backup to tape:
    http://www.ldas.ligo-wa.caltech.edu/ldas_outgoing/tapecontrol/logs/clientlog.html

    tapecontrol log for LLO backup to T3s:
    http://www.ldas.ligo-la.caltech.edu/ldas_outgoing/tapecontrol/logs/log.html

    tapecontrol log for LLO backup to tape:
    http://www.ldas.ligo-la.caltech.edu/ldas_outgoing/tapecontrol/logs/clientlog.html

    General Computing (Wallace)
    MIT:
    (Keith)
    -SSHv1 investigation (who/what products still uses it)
      began shutting down v1 daemons
    -Windows software installation support
    -Bundled cygwin for windows users. This is a Xwin pkg.
    -Acquired quotes for networking equipment to NW22
    -Investigating AP2000 wireless hubs

    Livingston:
    (Tom)
    -We have ordered a DVD writer for testing. There is a growing need for people
    to be able to move large data files to their laptops, etc., and we hope this
    will be a solution.
    -We are continuing to prepare for the E7 run.

    (Shannon)
    -Working on a web page for several people here where they can post
    data files that they would like to archive.  Revising the operations
    checklist in prep. for E7.

    Hanford:
    (Christine)
    -Preparations for E7 run and getting things ready for Lisa to help out
    during that time period.

    CIT:
    (Mike)
    -Finished up loading a laptop and put back into loaner pool.

    Phoenix,
    She picked up the goner.scr virus; I ran virus scan tool to clean up
    computer and updated virus scan software.
    -Swapped out Ken M.'s old PC with a new Dell 2Ghz computer fully loaded with
    all General Computing Software and Engineering software.
    -Worked on all the NT servers for system errors, updating virus can software and
    compacting database on ANTARES.
    -Swapped out multiple old PC's that I had in my office to try and replace
    Barbara's old PC for a LINUX load but had no success. Larry mentioned that
    we would have a newer computer freed up by the end of this week to replace
    this computer.
    -Ran multiple tests for NSF videoconference.
    -Have been studying Active Directory Sever 2000 at home and have come across
    with some problems with Active Directory which I corrected by demoting the
    server using the 'dcpromo command' this process uninstalls Active Directory;
    something to keep in mind that you will lose all user accounts your Security
    Access
    Manager is wiped clean the only account that will be left is ADMINISTRATOR
    and the guest account. To install active directory just issue the command
    again 'dcpromo' and this will start a fresh Active Directory install. This
    will save a lot of time rather than wiping your server and running a fresh
    2000 server install.

    (Lisa)
    - Finished compiling the new mail server. This included sendmail, elm, imap and
    ipop.  It still needs a little more work but the majority is done now.
    -I have a running prototype of an IP/inventory system running.  It currently
    has entries for the pc's (m1 - m101).
    -Usual round of user support.

    (Larry)
    -Worked out the logistics of a ISDN video conference with the NSF. After much
    running around and checking things out, we were finally able to get it setup
    through the Chemistry Departments unit. Thanks to Tom Dunn and testing with Mike
    P. this side of the system worked pretty well.
    -Reconciled P-card and worked a number of other procurement related issues.
    Still a few more things to clear up with Foundry on the network equipment but it
    looks like we won't have any major problems. I did have to contact SUN to get
    the Media upgrades. They informed me that they are no longer going to send them
    out automatically and that I will have to request them.
    Had to redo an order for a new printer going to Wilson House. Appears to have
    gotten lost in the cracks.
    -The new fiber runs have been delayed until January because of asbestos cleanup
    taking place in the tunnels on campus.
    -Worked on a new web server. It is now functional but still have a number of
    changes to be made. Also, working on the LIGO web server upgrade.
    -Worked on a number of documents; Policy, security plan and the Annual report.
    -The usual of updating e-mail aliases and accounts.

    (Veronica)
    - Updated various parts of the LIGO website.
    - Project Science website: disabled the registration submitform;
    last-minute additions can be accommodated through an unpublished link.
    - GWADW 2002: working on the graphics/layout.
    - CaJAGWR: working with John Armstrong on the seminars schedule and room
    arrangements for the next term
     
     


    LIGO II/Advanced R&D (Sanders)


    From Calum Torrie:

    Advanced LIGO
    Modelling and Testing for proposed Prototype Suspensions:
    The SolidWorks class Janeen and I were supposed to be going on was cancelled. We will now be going in January and February.
    I have started the tutorials which came with the 2001 version of SoildWorks.
    I met with Mark Barton to discuss the two models. I think real progress was made.
    We met with representatives from Adroit Automation to discuss a possible robotics arm for transporting the heavy optics. Helena, Janeen, Gary, Phil and I had a subsequent meeting to discuss the proposed design in detail.
    The workshop has finished the parts for the pre-prototype tests we are going to do in January. Now that I have all of the parts, both from the shop and from outside companies, I can put another 3 parts for these tests into workshop.
    I have been continuing to look at the Simulink version of the triple pendulum model with Norna Robertson at Stanford and Ken Strain in Glasgow.
    I have been continuing my weekly classes in the machineshop.
    As I mentioned last week, next week I am visiting Glasgow on Thursday and Friday.
     

    From Rich Abbott:

    The manufacturer of the capacitance position sensors is shipping 9 of the 12 units to me for test. I will check them as soon as they get in.

    Dave has finished taking data on the voice coil actuator driver electronics and we are in the process of making a prototype with all the features included (monitors of temperature, current, protection circuits, voltage etc.).

    The prototype schematic and parts list for the high current driver module is complete. Board layout will begin this week and orders will be placed for materials. No sign yet of the capacitance position sensors even though the manufacturer stated that they were to have been shipped last week.
     

    From Mark Barton:

    This week I succeeded in identifying all the sources of the slight differences in vertical mode frequencies between Calum's model and mine. All but one were small known differences in starting assumptions, and I fixed the remaining one which was a 1-x vs 1/(1+x) error in the formula for working back from the stretched wire lengths to the unstretched lengths. Since then I've been working on the horizontal degrees of freedom.

    This week I started with more work on the comparison of my suspension model against Calum's in the horizontal DOFs. I checked for a lot of potential errors, but didn't find anything. There are still a few small discrepancies that are probably ignorable for production work but which I'd like to understand better. However for lack of immediate inspiration about how to isolate them I switched to adding the provisions for exporting state-spate matrices to Matlab. So far I have a Mathematica routine that exports matrices in .m (text) format and a number of utilities for pasting together state-space matrices from elasticity, mass, and coupling matrices.
     

    From Peter King:

    Advanced LIGO PSL
    I requested a quotation for the 10-W amplifier and associated power supply, from Lightwave.

    The quotation for the supply and delivery of a 10-W amplifier from Lightwave Electronics came in. I will process the paperwork when I get back on campus.
     

    From Janeen Romie:

    Working on AdLIGO MC suspension. Working with Helena on holding arm.
    Working on small 40m tasks.
    Making sure all is set for N. Robertson's visit in January.
     

    From Jay Heefner:

    Advanced LIGO DAC Module
    ============================
    - The specifications document is complete and the RFI will be sent out when
    Irena gets back on Jan 7.

    From: Helena Armandula <ahelena@ligo.caltech.edu>

    Advanced LIGO coatings:
    Lyon - Eight substrates (4 thin, 4 thick) have been processed.
    During the coating of the first batch, the thin substrates rotated on the fixture leaving a mark at the very edge of the substrate.
    For the second run the fixture was re-worked and there were not problems.
    These parts are finished. The thin parts will be shipped to Caltech and the thick substrates will be shipped to Glasgow  on January 7th according to J. Hough's request.

    As scheduled, we shipped 4 thin substrates for the next runs. Glasgow is handling the shipping of the thick substrates.

    On January 4th, some of us will be visiting MLD's up-graded coating facilities.

    Coating Characterization: 4 coated substrates coated by different vendors were evaluated by Scanning Electron Microscopy (SEM)
    The working resolution of the instrument (30 to 100 nm depending on the sample studied) was not enough to resolve the surface profile of the film.
    Field Emission SEM with a spatial resolution of ~ 15 Angstroms should be a more adequate instrument for this test.
     

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

    Bob Oreb reports on the homogeneity compensation work at CSIRO:
    So far we have some very encouraging results with two of the methods- the IBE and the selective coating. With both of these methods we have been able to demonstrate the required spatial resolution (10 mm) and the range of relief (100nm). We feel confident that we will also be able to shortly demonstrate the gradation of relief (10 nm). The micro-roughness measurements we have done to date indicate that the IBE does not roughen the surface beyond 4 Angstrom.  With selective coating we have not yet measured the roughness degradation. With the pressurized fluid polishing method we are still in the process of optimizing the polishing parameters. All the equipment has been set up and we are investigating different configurations (e.g. nozzle size, pump pressure, relative position of test surface, polishing slurry composition etc). So far we have not been able to demonstrate suitable removal or polishing rate on sapphire with this method but the tests are continuing.

    Joel Askinazi at Goodrich reports that they are ~2 weeks away from finishing up the compensating polish of the 250mm piece.  They have gone through extensive calibration of removal rate working on both a and m axis sapphire.  They understand the removal rate well now.  They have been through 1 cycle of compensation and reached an rms of 49 nm, they predict that they will reach their goal of 15 nm after the next run.  They also report that swirl marks are left by the tool on a-axis material but not on m-axis material.  They are confident that they can put the part on pitch and smooth these swirls, but note that it is an extra step.

    From: Riccardo DeSalvo <desalvo@ligo.caltech.edu>

    @ Pasadena
    Charlotte
    Writing final report before departure

    Charlotte, (Riccardo)
    Creep measurement ongoing.

    Jan
    Prepared first MoRuB melt, and sent it to Carnegie Mellon for spin cast
    into ribbons, it may be spin cast before Christmas.  Should yield 100 g
    of test samples 3 mm wide, 20 micron thick.  Due to vacation period, no
    new melts will be made until mid January.

    @ Pisa
    Alessandro,
    Continuing tests on electropolishing, tested second solution, achieved
    very good polishing control with pulsed operation.  Noticed a lot of
    tensioning and acoustic emission during polishing.  Will try annealing
    before polishing.  Following Ultrasound mill construction.

    Alessandro, Riccardo, Gianni
    Preliminary design of flex joint structure for mirror hook-up, ready to
    go with an engineering prototype.  Adapted support design of stress
    strain machine for smaller MoRuB ribbon tests.

    @ Hongo
    Akiteru, Ida
    After last week’s trouble, for lack of control authority, to lock SAS
    suspended mirror to grounded M&M, built small suspended beam splitter
    and end mirror for further M&M tests, before switching to the FP with
    the second SAS suspended mirror.
    LATEST NEWS 17th Dec.:
    Hello all,
    We have just managed to lock the small test michelson interferometer
    today.
    Eventually the lock was achieved with the digital control system, with a
    UGF
    at 100 Hz, the dc gain less than 100.
    This may not sound a great achievement, but I think we have now
    established
    all the local controls needed to damp the mirror motion and we could be
    confident that the FP control is also feasible.
    The small interferometer will be used to measure mechanical transfer
    function of the entire tower, excluding the IP. We will try to finish
    the
    measurements by the end of the year and start the FP experiment in early

    January.          Akiteru
    NOTE:  This result was achieved in air, piloting the full mirror with
    Low Frequency actuators against air buffeting,  it will be much easier
    in vacuum without perturbations and much more so when locking SAS to
    SAS.        R.D.
     

    Nishi, Riccardo
    Installed second tower sensors and actuators, cabled all sensors and
    actuators, getting ready for final tune-up.
     

    Riccardo
    Visited NAO on 13th Dec, meeting with Seji Kawamura, Takahashi Ryutaro,
    Koji Arai, discussing remaining technical problems for SAS
    implementation in TAMA 300.  Project expanded to 8 towers (now including
    injection bench, mode cleaner and power recycling mirrors) but delayed
    installation to 2004.
    Visited Kashiwa campus on 12th Dec., meeting with Kazuaki Kuroda and
    Kazuhiro Yamamoto.
    Cryogenic FP working, been shown data of thermal conductivity in
    sapphire fibers as function of fiber diameter.  Bigger fibers show
    better specific conductivity than smaller ones, still almost ten times
    better than bulk sapphire.  Quite some space for improvement.
     

    Akiteru, Ida, Nishi, Kenji, Kimio, Riccardo
    Defined improvements for SAS, the angular modes are presently too low in
    frequency to be damped by inertial damping and they are treated using
    signals from optical sensors.  Stiffer suspension wires (maintaining
    thin neck at the double nail heads to maintain soft pitch and roll) will
    be studied to increase the yaw frequency and fall inside the inertial
    damping frequency band.  The stiffened wire will be tested in the
    Caltech TAMA-SAS test tower and implemented later in Hongo.
    Discussing other SAS limitations.  Surprising, despite the small
    required forces, the actuators may be a limiting factor; it is tough not
    to spoil the IP performance.  There is still place for electronics
    improvements, lower noise coil drivers may help in future.
    Studies will be made by Hongo students on options to developed an
    advanced version of SAS:
    One option is to replace the inertial damping with passive damping.
    Discussion: Even if successful, the LVDT controlled actuation would
    remain to provide ULF positioning, and the accelerometer feedback may
    remain to provide further suppression of microseismic peak (active
    attenuation below the Hz) if what delivered by IP will not be
    succesful.  Another idea is to study the possibility to implement an
    active attenuation stage after the IP/F0 preattenuation.  Discussion:
    Key instruments will be the accelerometers.  Sensing of the
    accelerometer test masses will be the easy part, actuation is probably
    more difficult, but the main limitations may come for the mechanics of
    the test masses.
    Other ideas will be explored.
    Kenji would use the TAMA-SAS prototype, modified to support an optical
    bench, to make a thermal noise interferometer using the 3 meter FP as a
    mode cleaner.  This would also work as a path finder for a TAMA 300 SAS
    suspended optical bench.  The system could test advanced mirror
    suspension performances.

    Riccardo gone back to Pasadena 15th Dec.
     


    For additional information about this report, contact sanders@ligo.caltech.edu