Caltech: Drever, Lazzarini, Mours, Shawhan, Zweizig
     Dublin: Ottewill
     LHO: Ito, Landry, Savage, Schofield, Sigg, Whitcomb
     Michigan: Riles
     Syracuse: Penn, Saulson

Preliminary E3/E4 Investigation Reports:

• E4 Lock Losses (KR reporting)

(See preliminary report web page for details and plots)
• A striking correlation was documented between ability to acquire / retain lock and seismic noise in the 1-3 Hz band, suggesting that many lock losses were seismic in origin. But no smoking gun (e.g., coil saturation) was observed in a sample of losses thought to have been seismic.
• There were other classes of lock loss observed, however. One class was coil saturation after tidal drift (expected and somewhat gratifying to see).
• Another class appeared to be a servo instability with exponential growth in coil current of 5 ms time scale. The source is not yet understood.
• Another class was gradual growth of a large, narrow 686 Hz oscillation in the arm control signals that caused end-mass coil saturation. The narrowness suggests a mechanical or electronic resonance, not servo instability. Several BSC down tube resonances are expected in this frequency range. In an e-mail comment after the meeting, Rana reported further study of this oscillation that suggests that it is not a servo instability: a harmonic at twice 686 is seen, and a change in servo gain did not change the frequency of the oscillation.

 
• E4 Frequency Noise (R. Adhikari reporting)

(See preliminary report web page for details) His automobile's ignition acquisition failure prevented Rana from attending the telecon. He will report on the results posted here at the next detector characterization telecon. Highlights include:
• Measurement of common mode rejection of factor of ~20
• Evidence of shadow sensor noise dominating the differential mode noise floor
• Preliminary investigation of seismic noise coupling into the mode cleaner length noise

 
• E3/E4 Seismic Noise (D. Greenwood reporting by e-mail shortly after meeting)

Dick is investigating a phenomenon common to the E3 and E4 periods: a persistent 10 Hz seismic signal measured at the EX (but not EY) station that rose during the day and fell at night. It was also detected by the LLO external seismometer array during E3.
In addition, the EY seismometers measured alarming ~30 Hz signals that sometimes contributed > 50% of total seismic activity in the 1-50 Hz range. Finer resolution revealed two sharp peaks at 29.3 and 29.7. More will be reported at the next telecon.

• Likely dates and interferometer configurations - S. Whitcomb

As announced earlier, E5 is tentatively planned for the first weekend in August (Fri Aug 3 to Mon Aug 6). It is strongly hoped that the LHO 2K will be in recycling configuration and the LLO 4K in recombination. It is also possible that the LHO 4K will be in recombination. If, however, the LHO 2K is not stably recycled by early August, the run may be delayed three weeks to Aug 24-27. This will be the first engineering run data taken with a recycled interferometer.
 
• Investigations and E2-E5 reports - KR
• Many E2 final reports are still missing. A web page contains links to results and final reports of the E2 investigation teams. Only those reports that are unambiguously final are linked to it at the moment.
• E3/E4 investigators are asked to turn in final written reports no later than the August LSC meeting and to make presentations at that meeting. All teams should give preliminary reports at a detector characterization telecon before the LSC meeting.
• It may be appropriate to do some tweaking of the investigation organization for E5, based on E3/E4 experience. Since E5 is the direct precursor to the E6 upper limits run, we may want to refocus some of the investigations to address particular issues the upper limits groups are worrying about. Suggestions for modifying the present E4 lineup (which is an excellent starting point) are requested. An e-mail will be sent to the entire detector characterization soliciting suggestions and volunteers.
• DMT software developers are strongly urged to get ready for E5. Several DMT monitors proved quite useful in E4, but more are needed, and many of the existing monitors need improved online documentation and information display.

• General - J. Zweizig

E4 preparations and the run itself took up about two weeks of John's efforts. At LLO a 2-cpu Pentium III (1 GHz) linux box has been brought up to run online DMT in parallel with delaronde. Despite quoted speed differences, John finds that one linux cpu performs at about the same effective speed as one sun E-450 cpu. The cpu power per dollar is better, however, with the linux machine. John notes that byte swapping contributes to but doesn't appear to dominate the linux time per job. The jury is still out on whether large improvements in the linux performance can be achieved with software changes.
Motivated by an interesting microphone pickup in E4 (see lock loss report above), John got a program running on the LLO suns that converts any data channel to audio for the listener's pleasure.
John has also been documenting and upgrading parts of the DMT infrastructure. The current development version now uses root 3.01.03 (old was 2.25.03) and uses a new gcc compiler version too, which is reputed to give better code performance.
John and Daniel have been preparing for next week's DMT camp for which seven persons have signed up. Daniel has written up lectures that will be posted on the DMT home page (and linked to the DetChar bulletin board).
• Histogramming - M. Ito

Masahiro is creating a new histogram class within the DMT which will be used to transport information from the DMT background processes to the DMT viewer program (monserver/monclient infrastructure). A header file has been given to John and Daniel for comment. On the DMT viewer end, the DMT histogram class will be converted to a root histogram class so that root's powerful display code can be exploited. Masahiro has looked at what is required to create a histogram gui and believes he can have a first version of the entire package ready for E5.

• Line noise:

 
• B. Allen, A. Ottewill (Adrian reporting)

Adrian has been working mainly on the multi-taper line removal code (already in the DMT) for the LDAS data conditioning API and will be attending the LDAS camp next week. He has worked a bit on getting the dmt viewer running on his computer at Dublin to see plots generated by background monitors running at Hanford. He succeeded in getting the viewer program running, but had trouble seeing the plots, a misunderstanding which was cleared up during the telecon. The line monitor code will be the first to be integrated into the dmt viewer, followed by the correlations monitor code.
 
• S. Klimenko (not present)

 
• A. Sintes (not present due to conflicting GEO meeting)

• Characterizing seismic noise:

• E. Daw (not present)

 
• Inter-channel correlations:

• B. Allen, A. Ottewill (see above)

 
• Bilinear cross-couplings

 
• S. Penn

Steve's monitor is now runnable on the online suns (developed on his linux laptop). The executable and source code can be found in the spenn directory on delaronde. Called xbispec, the monitor allows real-time display of either bispectra for a single channel or cross-spectra for 2-3 channels. Steve is working on a version to display normalized bi-coherence. He will give instructions to interested commissioners and operators on using the program (KR offered to make a link on the DetChar bulletin board page for any web instructions). John suggested this program, which is cpu-limited at high requested bandwidths,  would be  suitable for running on the LLO linux. Steve reported being unable to ssh directly to delaronde from Syracuse. KR believed that to be a deliberate security decision, but John and Daniel thought that decision to be inappropriate and volunteered to look into it.
• Operational state:

 
• D. Chin, K. Riles (KR reporting)

Dave has added several new operational state conditions, designed to flag simple global changes to channel behavior, but has spent more of his time on integrating the lock loss monitor into the dmt viewer. He has a private version working now that allows display of lock history in the viewer and will be adding some bells and whistles in the next few weeks. New versions of the lock loss monitor and of a dmt-viewer-supporting servo monitor will be ready well before E5 and exercised on E4 data for shakedown.

• Bandlimited RMS

 
• E. Daw  (not present)

 
• Time / Frequency plots

 
• S. Mohanty (not present due to conflicting GEO meeting)

E-mail report: not much progress since last month, working on test of prototype background monitor for transients. Search algorithm applied recently to E3 data and report in progress.
 
• J. Sylvestre (not present)

 
• Non-Gaussian noise

 
• S. Penn (nothing new reported)

 
• S. Finn, G. Gonzalez, P. Sutton (not present)

• Power spectral transients:

 
• S. Mohanty (see above)

 
• Servo instability:

 
• D. Chin, R. Gustafson, K. Riles (see above)

 
• Event catalog:

 
• J. Sylvestre, R. Weiss (not present)

• Impulse recognition:

 
• M. Ito

Masahiro has focussed solely on histogramming work lately (see above). KR noted, however, that Masahiro's  glitchmon monitor had generated some very interesting triggers in the meta-database during E4 (see lock loss report above) and encouraged others to look (with the guild program) at those triggers.
• Magnetic field and seismic transients

 
• R. Frey, R. Rahkola (not present due to Ph.D. candidacy oral exam, which Rauha passed )

Not much progress on magnetic field monitoring, but Rauha has developed a seismic alarm for control room operators, which is almost working now.

A.O.B.

• Next detector characterization teleconference: Friday July 13 at 11:00 a.m. EDT (8:00 PDT).

(NOTE: This will be the second Friday in July, not the first. KR will be travelling on the 6th.)