Dec 17, 1991 - Blue Sheet

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Project Progress Summary

December 17, 1991

The next Project Progress Summary will appear on January 7, 1991. Have a happy and safe holiday!

FET Operations

  • A good bunch length measurement was completed with 100 MHz BPMs as pickups. We are well

within longitudinal emittance specifications, and results agree with PARMELA simulations.

  • We investigated 60 Hz steering on the beam and were able to reduce but not eliminate it.
  • Substantial time was spent training beam operators as well as performing CW beam RF tests.
  • Quantitative measurements of dispersion in the 180° bend lead us to believe we can suppress it to centimeter values.

SRF

Cavities:

  • Tested 89/101 pair on 12 December and 83/84 pair on 13 December; both exceed specifications. Next assembly: 131/132

HOM Loads:

  • Completed 100 production loads 7 December. All the in-house loads are now complete.
  • The sole source justification for obtaining the special glassy carbon ceramic from the qualified vendor is being reviewed. This procurement will finish all the parts needed to complete the balance of loads.

RF Windows:

  • Four more production windows were turned over to the cavity assembly group.
  • Eighty raw ceramics are being machined. An additional 125 pieces are on order. These parts will be metallized and brazed by production vendors.

Cryomodules:

  • Cryomodule #8 (for the second position in the north linac) has been successfully tested and is capable of delivering 20 Me V at the design heat load.
  • In addition, as expected, all vacuums -- beam waveguide and insulating -- are excellent.
  • Cryounit #40 was transferred to the cryomodule assembly area and cryounit #41 in assembly is being welded into the helium vessel.

Arcs

Magnets:

  • Magnetic measurement of the east arc dipoles was completed.
  • Sixty-three dipoles have been installed in the east arc.

Survey/Alignment:

  • Stand alignment in the NE matching region has been completed.
  • Stand alignment in the SE matching region has been started.
  • West arc stand alignment continues.

DC Power:

  • One trim rack placed in the south access building. Total is now 34.
  • Installed unistrut and tray in the east spreader.
  • Made tests of dipole hookup in the east arc and of cable dressing unistrut for north linac warm sections.

Diagnostics:

  • Two M15 BPMs were received and rejected because they were out of tolerance.
  • The recirculation experiment kicker was successfully tested.
  • The bunch length measurement was tested and yielded a resolution of about 1 psec.

 

Linac

RF:

  • Digital group found problem of occasional memory loss an incorrectly programmed PLD.
  • Fixture is complete for production of 55' RF feedback cables. Several cables were fabricated and passed QA. Full production starts this week.

Ops Electronics:

  • All cables have been pulled and terminated for NL RF test with the exception of the gate switch.
  • NL CARM cable 90% complete. SL started.
  • East arc BLM cross connect and trunk cabling complete.
  • East arc diagnostics field cable installation started.
  • SL to MCC fiber optics terminated, tested and ready.

Software and Controls:

  • Real time exec operating system working for RF module.
  • Negotiations underway with HP to solve HP 720 GPIB problem. BPM noise filters installed, automatic chopper tuning program ready for test.
  • Second roll-around RF cart equipped.

Cryogenics:

  • Operational problems occurred with the CfF. Expanders, K-10 blower, and recovery compressor were repaired.
  • Operation of turbo #4 at CHL resulted in bearing failure. Turbine is being shipped to France to be returned next month.
  • An electrical problem still exists in the 2 K box and may require cover to be removed.
  • Kaiser air compressors have been repaired.
  • By 12 December, cryosystems were operating normally.

 

Physics: Collaboration meetings for both Hall A and Hall B will be held January 10 and 11.

Civil Construction

End Stations Underground (Package A):

  • Continued crane-related work in Halls B and C.

End Stations Above Ground (Package B)

  • Completed the footing for SB #1 and started forming and placing foundation walls.
  • Completed installation of the roof fans on the ESRJSB #2 roof and continued installing siding and closures and door frames.
  • Completed the membrane roofing system and the siding on SB #5. -

Miscellaneous Projects:

  • Continued relocating sprinkler lines, installing LCW and instrument air lines, and applying the floor coating in the accelerator tunnel.

Support Services

Stockroom:

  • Inventory progressing well -- transportainers and EEL completed.

Machine Shop:

  • Manufacturing cold trap parts for WBS 7.
  • Completed fifteen slant target bodies for WBS 2.
  • Began beam viewer cylinder modifications for WBS 5.

Fabrication Planning:

  • Two sets of HMS detector plates are planned to be processed through procurement this week (Hall C).
  • Sixty-eight assemblies of the 45 Me V spectrometer flex plate processed. Awaiting quotes (WBS 2).

Educational Activities at CEBAF on Saturday, 4 January

  • On Saturday, 4 January up to 250 minority high school students will attend a career awareness day at CEBAF from 9:30 a.m. to 3:00 p.m. Activities will include guest speakers, exhibits, and lunch. · Sponsoring organizations are CHROME, Cooperating Hampton Roads Organizations for Minorities in Engineering, and V AMPSE, Virginia Alliance for Minority Participation in Science and Engineering.
  • Simultaneously, 30 middle school girls with math anxiety will be visiting CEBAF to improve their interest in math and to meet with role models to increase their awareness how math is used in diverse jobs at CEBAF. This program, called GAMES (Girls and Math Equals Success) is funded by NSF. The girls attended an intensive program last summer at Christopher Newport College and now meet monthly during the school year.

Winter/Spring 1992 CEBAF Science Series

Flyers for the January through May CEBAF Science Series presentations are being distributed. The next presentation, on Thursday, January 9, will be "The Nature of the Nucleus -- Where We've Been and Where We're Going," by Nathan Isgur. Mrs. Pat Kirby (husband: Jud, of Project Management) and Mrs. Ursula Mecking (husband: Bernhard, of Physics) are moving on after two years of valuable contributions to the CEBAF Science Series, where they have served the post-presentation refreshments. Any CEBAF spouse or staff member interested in volunteering to help at future Science Series should call Steve Corneliussen at 249-7582.

WARNING: A computer virus "michelangelo" was discovered on discs obtained from SLAC.