Jefferson Lab Weekly Briefs August 17, 2011

Jefferson Lab Weekly Briefs
August 17, 2011

12 GeV Upgrade

Excellent progress continues to be made on the work planned for the Six Month Shutdown. Magnet rework and re-installation of the south half of the east arcs has been completed and they are back under vacuum. Work is proceeding well on getting the magnets in the north half of all arcs re-installed. All arc magnets have now been refurbished, with only a few left to measure and re-install. The first 12 GeV cryomodule has been installed in the tunnel and connected to one of the new radiofrequency zones. The expansion and upgrade of the Personnel Safety System was completed on schedule last week, which permitted in-tunnel testing of the new cryomodule-RF zone to start this past Monday. The second zone of RF has been completed and good progress has been made on the third. Three more cryomodules are at various stages of assembly.


In the injector, injector experiment (PEPPo) checks continued. Lockup of the south linac and a PSS function test went well, with no problems found. Tunnel cleanup was completed in preparation for daily lockup of the south linac for RF commissioning. Cryomodule 2L24 is in place and hookups are completed. Some RF commissioning and beam switchyard penetration grouting has begun. Lastly, the Central Helium Liquefier mag lev bearing control cabinet has been rebuilt.

Free-Electron Laser

The FEL team continued to prepare the gun and drive laser for 350 kilovolt operations. The quarter cryo booster was brought back into operational status. The rest of the cryomodules have been brought into RF operation. The team has a few remaining tasks to complete next week on the machine front end and then beam operations will be ready to recommence.

Center for Theoretical and Computational Physics

The role and implications of spin-flavor symmetries that emerge in Quantum Chromodynamics (QCD) for a large number of color degrees of freedom have been investigated in the real world, where the number of colors is equal to three. This was carried out in a new article by investigating the different decays of negative-parity baryon resonances where π, η or Κ mesons are emitted. This study provides insights into those symmetries and also predictions, which being based on a study that to a large extent is rigorously connected to QCD, should serve as important tests of the strong dynamics of QCD. A main motivation for this kind of study is the N* experimental program at JLab and the quest for understanding strong QCD from the results of that program.


The Machine Shop is presently manufacturing:

  • Two each assemblies, torus magnet weld test coil case for the Hall B 12 GeV Upgrade
  • One each assembly, accelerator injector positron Faraday cup assembly
  • One each assembly, high-threshold Cerekov counter mirror mold facet block 4 for Hall B CLAS 12
  • Efforts continue on the cavity resonance monitor crab cavity for Argonne.


The shop has received a mostly positive response from its customers on the use of the electronic Machine Shop Work Request system. The shop has processed 201 job requests since July 5.




Environment, Safety, Health and Quality

Warning Tapes Provide Information for Your Safety
During the construction and other type of work around JLab, crews have erected barrier tapes to warn and notify people of hazards or conditions. Recently, a number of JLab employees have been observed ignoring these barriers. Warning or barrier tapes are used for a variety of purposes
. Never enter an area that has been taped off unless you have the proper training to do so. Areas that have been taped are off-limits to anyone who is not specifically trained, properly protected and authorized to work beyond the tape.


JAG Luau Set for Today
The JAG Luau is open to all lab employees and their families, users and students, and will be 3-6 p.m. on Wednesday, Aug. 17, on the lawn behind the Residence Facility. Refreshments will include summer favorites: hamburgers, hotdogs, chips, cold beverages and special treats. For more information, visit the JAG website.

United Way School Tools Drive
The United Way School Tools Drive is now underway. Collection boxes for donations of school supplies are located in the VARC, MCC, CEBAF Center and ARC lobbies through Aug. 25. New school supplies for students of any grade level may be placed in the boxes. Appropriate items include pens, pencils, student scissors, crayons, spiral notebooks, 3-ring binders, binder paper, pocket folders, rulers, protractor/compass sets, etc. For more information, contact Joshua Cameron, x7628.

Last Chance to Sign Up for 2011 Day of Caring
The 2011 annual United Way Day of Caring will be Friday, Sept. 9. Volunteers will help provide much-needed help for senior citizens in multiple communities to remain safe and secure in their homes. No prior experience is required. Volunteers are asked to fill out the 2011 United Way Day of Caring volunteer participation form and send or deliver it to Joshua Cameron (Mail Stop MS 12B, CEBAF Center room B214) by 5 p.m. Monday, Aug. 22. Before turning in the form, each volunteer must have their supervisor's signature (in any open area) on form. For more information about the 2011 Rock the Block Day of Caring, visit the website.

Fed Travelers and Smartphone Apps
Love your smartphone and using apps to make your life a little easier? Federal travelers and others who use GSA's per diem rates can now look up rates while on the go with just a few taps or clicks, as GSA announces the new per diem rate app for the iPhone and BlackBerry platforms. The app is free of charge. The new app allows travelers to look up per diem reimbursement rates for lodging and meals and incidentals rates by location or ZIP code. Travelers can look up rates for the federal government fiscal years 2010 and 2011, with 2012 rates available later this summer. Visit GSA's per diem website for more information.

Tracking Thomas at JLab
Little Thomas is visiting all corners of the JLab campus. If you can identify his location this week, email Kandice Carter with your guess. Guesses are accepted through Fridays.

Congratulations to Jason Willoughby, Stephen Smith, Doug Higinbotham, Michael Haddox-Schatz, David Fazenbaker, Percy Harrell, Marcy Stutzman and Stephanie Vermeire, who were the first to correctly identify the Aug. 10 location. Honorable mentions go out to Harry Fanning, Dick Owen, Mike Martin, Aidan Kelleher, Casey Heck, Cynthia Eller, Michelle Shinn and Mike Davis. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.

JLab Calendar of Events

Aug. 18: Senator Mark Warner, CC auditorium, seating 2:30-2:45 p.m.
Aug. 22: Safety Shoe vendor onsite
Aug. 22-26: PAC 38
Sept. 5: Labor Day holiday; JLab closed