Jefferson Lab Weekly Briefs
July 18, 2012
12 GeV Upgrade
Detector construction for the Hall C Super High Momentum Spectrometer continues, with preparations started to aluminize and overcoat the mirror blanks for the heavy-gas Cerenkov counter. Winding of the third coil for the Q1 quadrupole magnet is complete. Soldering of the copper stabilizer to the superconducting SSC cable for the Q2, Q3 and dipole magnets continues, with the second major shipment of soldered production conductor having arrived at the magnet vendor. Production winding tooling for the dipole magnet is arriving at the vendor and being assembled. The sections of the support structure have arrived at JLab and are stored pending their move to Hall C after removal of Q-weak and the Short Orbit Spectrometer is complete. The first sections of the several hundred tons of Q2, Q3 and dipole magnet steel yokes have been cast and readied for final machining.
In the Long Shutdown labwide coordination effort, an essential tool is the integrated schedule. The integrated schedule, implemented by the Project Management Group in the P6 scheduling software, includes all activities that are relevant to the LSD, and allows for the planning and tracking of the work and manpower resources. Updating the schedule is an essential exercise: at the end of each month, the accelerator, the halls, the FEL, Facilities Management and Logistics and all parties that have scope of work in the LSD report their monthly progress. Those reports are collected and analyzed by Project Management and Integrated Planning and the LSD Team. The progressed schedule allows lab leadership to check on the LSD overall status. The progress collected at the end of June is positive and did not show any major problem so far in schedule or resources.
The FEL team continued its efforts to set up beam for the DarkLight experiment, successfully achieving 99.999 percent transmission through the 2 millimeter aperture for 100 kilowatts of continuous wave beam. The team also took some very interesting beam images with five orders of magnitude dynamic range for visualization of the beam halo.
Center for Theoretical and Computational Physics
A first systematic study of the effects of the input scale in global determinations of parton distribution functions (PDFs) is presented in a new paper. Although in principle the results should not depend on these choices, in practice a relevant dependence develops as a consequence of what is called procedural bias. This uncertainty should be considered in addition to other theoretical and experimental errors, and a practical procedure for its estimation is proposed. This is of relevance for future extractions of PDFs as well as predictions for present and future measurements in JLab experiments.
The new Document Repository and E-Sign process, an electronic signature and archival system for engineering documents (i.e. drawings, specifications, calculations, etc.), was launched July 1. Initial feedback has been very positive. As with all new systems, JLab employees continue to identify items that did not surface during testing. If you find issues or have other comments about the system, forward to Bridget Paul.
JLab Calendar of Events
July 18-20: 5th International Workshop on Thin Films and New Ideas for Pushing the Limits of RF Superconductivity
Environment, Safety, Health and Quality
Hot Cars Not Safe for Kids
Last Chance to Apply for Voluntary Separation Program
Governor's School Mentorship Program
JLab Community Invited to Intern Poster Session on Aug. 3
Tracking Thomas at JLab
Congratulations this week go to Casey Heck, who was the first to correctly identify the location for July 11. Honorable mentions go to David Anderson and Harry Fanning, with a late entry from Leo Ketchum. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.