Project Progress Summary
September 12, 1991
PAC5
The fifth meeting of CEBAFs Program Advisory Committee will take place next week at CEBAF. The
PAC will review the recently received second-round experimental proposals.
FET Operations
Around-the-clock FET operations have gotten off to a successful start. With seventeen shifts per week,
including a night shift that maintains RF, productivity is up because beam is available each day less than
an hour after nominal start -- sometimes within minutes. Among the recent accomplishments are:
- RF operational stability has improved substantially.
- Precise measurements have been made of energy spread upper limits in pulsed operation. The measured value is 2.7xl04, about four times better than the nominal specification.
- Beam has been transported around the 85 Me V recirculation beam path as far as the last viewscreen before reinjection into the cryomodules.
- CW beam was accelerated to 46 Me V at 135 microamps and sent to the straight-ahead beam dump.
- Maximum energy has been 46.9 MeV/c, and typical operation has been 45.8 MeV/c.
- All 22 cavities have been powered consistently for these runs.
- I&C operational proficiency continues to improve.
SRF
Cryomodules:
- The cryounit technicians are continuing work on three more alignment fixtures.
- A' has been removed from the test cave following completion of the loss-of-vacuum test.
Cavity Pairs:
- IA90/IA91 has had the two RF windows replaced for observation of multipactor coating. Placed in VTA on Friday and cooled down for testing.
- IA094/IA096 will have the windows and loads removed and the cavity pair given to the cryounit group for tuner assembly practice.
HOM Loads:
- Forty HOM flanges have been received back from Electro-glo three days early. They are being inspected. Forty more flanges have had final machining and will be sent for electropolishing.
RF Windows:
- Four more production windows are complete; three need RF testing.
- More windows are being electron-beam welded and leak checked. The milestone of 25 windows by mid-November will be met
Nb Pair Parts:
- Two more FPC extensions with the new dimensions were completed.
Am
Magnets:
- Accepted first articles of the extraction corrector dipoles.
- Arc quadrupole (QA) laminations passed a preliminary inspection.
- The first arc dipole was installed (with beam tube) in its permanent location.
Survey/alignment:
- East arc stand alignment continues at about six stands a day. It should be complete in one week.
- Preliminary work for locating Hall C reference points was begun.
- The final report on the Hall A floor plates was completed. Some plates were found to be up to 0.5 m out of position.
- A surface plate was leveled for the machine shop.
DC Power:
- Another trim rack was placed in the south linac service building. Overall total is now 29.
- The east arc cable tray installation is a bit beyond the 50% point.
- WBS 1 cable pulls completed in south linac sections 1 and 2.
Diagnostics:
- Procurement was begun for 150 BPMs.
Linac
RF:
- HOM filters were tested and found to meet specs from 1.7-2.6 GHz.
- Klystron tests continue. Several have failed on bandwidth and will be retuned by Varian.
Ops Electronics:
- 150 arc BPM CAMAC modules are being ordered.
- FET recirculator 1500 MHz BPM software was installed and is being checked out.
- East arc control fibers installed and terminated.
Cryogenics:
- Supported FET and test lab operations.
- Clean up of purifier at CHL continuing.
- Acceptance test schedule from CVI is on hold awaiting location probe from L'Air Liquide.
- A review of flow sheets for ESR has been proceeding this week. Markups due from Physics by 18 November for signoff. Design is proceeding.
Physics
- The detector group recently designed and produced prototype circuit boards for readout of Hall A's focal plane polarimeter prototype. The boards were made with the assistance of Tom Powers' team from SRF. The "Detector Meisters" also completed the design and produced the supports for Hall C's prototype hodoscope. Initial evaluation is underway for their mockup design of the CEBAF photomultiplier (PMT) base and housing.
Civil Construction
- Continued working on cleanup, leak repairs, and punch list items in all areas. Completed the Hall B dome.
- Continued installation of the crane support brackets in Hall C.
- Continued working on the storm drain system, site fine grading, roads and parking lot areas.
- MCI continued working on site utilities and the footings, underslab utilities, and floor slabs for SB #l, SB #2, SB #4. Completed erecting structural steel for the ESR building and plan to start erecting the steel for SB #4 this week.
Support Services
Stockroom:
- Withdrawal activity for the week: $23,904.02.
- Total monthly expenditures: $28,864.02.
- Material Handling Effort: moving of klystrons for WBS 3.
Fabrication Planning:
- Proceeding with effort to fabricate components for the "Alignment Quad Reference Fixture" (WBS 2).
- Processing component fabrication for beam viewer and harp near completion (WBS 3).
Voice Mail Training
In the auditorium on Wednesday at 11:00 a.m. and again on Thursday at 2:00 p.m., a 30-minute class will be held to familiarize CEBAF staff with the new phone mail system.
Conference Participation
F. Dylla is presenting an invited talk, "Correlation of Outgassing of Stainless Steel and Aluminum With Surface Treatments," at the American Vacuum Society Symposium this week in Seattle. Calls to DOE Germantown In the 301 area code, DOE Germantown telephone numbers now have a 903 prefix instead of 353. Last four digits have not changed.
CEBAF Science Series
The next CEBAF Science Series presentation will take place Wednesday, 20 November. Professors Hans von Baeyer and John McKnight of the William and Mary Physics Department will re-create in authentic G detail an eighteenth-century science demonstration. Students in grades six to twelve are targeted for the Science Series, but all are welcome.