Jefferson Lab Weekly Briefs
August 28, 2013
12 GeV Upgrade
In-tunnel testing of C100-9 is nearing completion, and testing of C100-10 is starting. Installation, including vacuum, diagnostics hookup and final alignment, is nearing completion for the beamlines in the main “racetrack” of the accelerator; leak checking for the vacuum system in the west recombiner is underway, and the last few pieces of beam tube are being installed in the west spreader. Completion of the beamlines is now focused on the extraction section, where alignment for hookup of the magnets and separator cavities is complete, and vacuum installation is underway. The radiofrequency waveguide circulator repairs are complete, and installation in the four zones in the south linac has begun. The in-place testing of the new box supply for arc 1 is nearing completion. Installation of the new box supply for arc 2 has begun. The new box supply for the beamline to Hall A will be shipped to Jefferson Lab this week. Retesting of the 4.5 Kelvin coldbox was delayed until Aug. 27, while some problems with the controls were resolved.
In Hall A, a 100-ton 48D48 magnet from Brookhaven National Lab was delivered to Jefferson Lab last week. It will be used for the 70 millisteradian Super BigBite Spectrometer in Hall A. The Jefferson Lab Program Advisory Committee has already approved four experiments that will use the magnet, and several additional proposals are on the way. The SBS program (mainly for the nucleon form factor experiments) was approved for construction by the Office of Nuclear Physics within DOE's Office of Science in May 2012. The arrival of the magnet presents a significant milestone in the construction program.
Center for Theoretical and Computational Physics
The measured value of the magnetic moment of the muon differs from the Standard Model prediction by more than three standard deviations. The largest source of error in the theory calculation is actually due to a dispersive analysis of experimental measurements that is used to determine the hadronic corrections. This recent work is the first four-flavor lattice QCD computation of these effects, and it confirms the dispersive analysis and the corresponding discrepancy with the Standard Model.
The Installation and Vacuum groups continue their work on the 12 GeV Upgrade in the accelerator. In the southwest corner of the main ring, the ZA, YR, YA and YB magnets have all been installed. These magnets all allow multi-pass beams and allow operations to split beam off to the experimental Halls A, B or C, or to continue on for another pass to increase their energy.
Additionally, beamline fabrication, installation, leak checking and pump down have been completed on the east spreader and east extraction regions. Low-conductivity water plumbing installation and beamline installation continues in the west spreader and west extraction, transport recombiner and west arc. Girders were assembled for the Hall D tagger line and the transport recombiner AT line.
Facilities Management and Logistics
Intermittent Power Outages Planned for Test Lab Aug. 29
Environment, Safety, Health and Quality
Travel Tips for Labor Day Weekend
VDOT also offers valuable information about planning your route, along with tips for getting live updates on local travel conditions on its website.
Hogan Drive Lane Closed
Jefferson Lab Graphic Identity Standards & Style Guide Now Available
Get Fit with Fido!
Next OnTarget Newsletter Scheduled for September
TIAA-CREF Onsite Individual Counseling Sessions
Tracking Thomas at Jefferson Lab
JLab Calendar of Events
|JLab Weekly Briefs is an ongoing publication providing information on the status of safety, accelerator operations, experiments, free-electron laser, reviews, upcoming activities and special events. Deadline for submission is every Tuesday by 10 a.m. Submit new items to: Public Affairs or contact Kandice Carter at x7263.|