Jefferson Lab Weekly Briefs November 26, 2008
Jefferson Lab Weekly Briefs
November 26, 2008
12 GeV Upgrade
Preparations continue for the awarding of civil contracts in January 2009. For the Hall D Complex construction contract, the Best and Final Offers (BAFO’s) were received on Nov. 21 and are now under review. For the Central Helium Liquefier (CHL) Building Addition construction contract, the initial technical review of the proposals is complete and clarifications are due from the Offerors on Nov. 26. In support of these two construction contracts, the Architect-Engineering firms will review submittals and shop drawings, perform milestone inspections, and provide office and field consultations. Fee proposals for these A-E services have been received and are under review.
In Hall A, experiments E06-010, Measurement of Single Target-Spin Asymmetry in Semi-Inclusive Pion-Electroproduction on a Transversely Polarized 3He Target, and E07-013, Target Normal Single-Spin Asymmetry in Inclusive DIS n(e,e') with a polarized 3He Target, are now in stable production mode. The installation of three narrow-band lasers has improved the polarized helium-3 in-beam target polarization from around 50 percent to around 60 percent.
PAC 34 Call for Proposals Due Dec. 15
The accelerator is settling into the time-honored groove of relatively stable high-energy beam delivery. The schedule for the next few weeks is to continue in this mode. Halls A & B received 223 hours of beam during the past week. The only notable repair was replacement of an electrical contact on the RSEP9A box supply.
Free-Electron Laser (FEL)
FEL staff members installed a new cathode, baked the gun and are already high-voltage conditioning. This is in only nine days from last operation. Staff members took advantage of the vault access during the gun work to make small but critical repairs and upgrades to the optical, vacuum, radiofrequency (rf) and diagnostics systems. Very significant progress has also been made in understanding the performance of the new drive laser with respect to phase stability.
A new paper (arXiv:0811.2440 [hep-lat]) reports the first unquenched calculation of the magnetic moments of the Δ(1232) and the Ω baryons using the background field method. This approach removes some of the systematic errors present in previous calculations by directly extracting the magnetic moment from the shift in the baryons' mass in a constant magnetic field. The results are consistent with experiment, with errors for the Ω comparable to the experimental ones and significantly smaller errors than experimental data for the Δ.
JLab's Safety Numbers
77 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
Environment, Safety, Health & Quality
Control of Nonconforming Material or Products Procedure
JLab procedure provides a process for positive control of nonconforming material or products, including identification, reporting and disposition. JLab uses a graded approach when dealing with any type of nonconforming material or product, and the procedure applies to nonconforming material or products labwide, whether just received, during assembly or while in use.
A subset of nonconforming material is suspect/counterfeit items (S/CI); because of the significance of S/CI within the DOE complex and special requirements for their reporting and disposition, JLab has a defined program to manage these issues.
Computing and Networking Infrastructure (CNI)
Windows Active Directory Update
Calendar Server Work Over Holiday Break
JLab Colloquium and Public Lecture
Children's Holiday Party
Toys for Tots Donation Drive
Calling All Amateur Interior Designers: Ready, Set, Decorate!
Children's Holiday Party Volunteers Needed