Jefferson Lab Weekly Briefs
March 13, 2013
12 GeV Upgrade
Conventional facilities construction for the 12 GeV Upgrade will resume with the award of a construction contract to upgrade the air conditioning systems in the North and South Linac Service Buildings. Approximately 30 tons of cooling will be added to each service building to handle the heat load from the new 12 GeV radiofrequency zones. The vendor site visit was held on March 12; vendor proposals are due March 28.
There was no Office of Naval Research effort on the main program this week, but Joint Technology Office work continued in optics and FEL simulation. The FEL team participated recently in the Basic Energy Sciences Advisory Committee meeting as observers. A new study of future light sources has been requested by Bill Brinkman, which will be monitored closely.
Center for Theoretical and Computational Physics
A new paper examines the QCD evolution of the helicity and transversity parton distribution functions, including their dependence on the parton transverse momentum. Using appropriate definitions of these polarized transverse momentum dependent distributions (TMDs), the dependence on the factorization scale and rapidity cutoff is derived. The results will be essential for phenomenological applications, especially for the analysis of the future JLab 12 GeV data.
The Installation group has completed the removal of the 6 GeV transport channel recombiner magnets and stands. The new floor-to-ceiling stands for this region were assembled and installed. Stands for the second extraction region were also assembled and installed. The beam switch yard lines A and B have had all the girders and dipoles removed for upgrade work. Additionally, work continues on the removal of line C magnets. The new line D pedestals have been installed up the ramp to the shield wall. Girders and dipoles were installed in the second spreader and low-conductivity water work is ongoing there, as well as at the first recombiner. The Vacuum group has been supporting beamline work in Hall A, cleaning and leak checking vacuum chambers for septa magnets, continuing with girder rebuilds, and connecting warm region girders in the linacs.
JLab Calendar of Events
March 13: Colloquium and Public Lecture
Environment, Safety, Health and Quality
JLab workers use acronyms or abbreviations by the score. In Industrial Hygiene, the acronyms TLV and PEL are frequently used in reference to dusts, gases and fumes. TLV and PEL represent Threshold Limit Value and Permissible Exposure Limit, respectively. Both refer, for the most part, to the allowable concentration of dusts, fumes and gases in the air for a chemical (other hazards such as heat, noise and etc. also have TLVs). Each concentration is based upon an eight- or 10-hour time weighted average exposure for a five-day work week. Studies and experience have determined that the typical adult worker can be exposed to this concentration for a 40-year working lifetime and not develop an adverse health effect. JLab uses the lowest exposure limit, which is generally the TLV.
Exposure concentrations ascertained from quantifiable air monitoring at JLab are generally either not detectable or significantly below these exposure limits. If you have questions regarding TLVs or PELs, contact either Dick Owen, x6381, or Jennifer Williams, x7882.
Got a Green Thumb? Take the JLab Garden Club Survey!
2013 Annual T-Shirt Contest Is Underway
Previous winning JLab T-shirt entries are available for viewing online.
Reminder: Tornado Response Survey
Colloquium and Public Lecture: The Origin(s) of the Heavy Elements
Tracking Thomas at JLab
Becky Mosbrucker correctly guessed the location for March 6. Honorable mentions go to Maurizio Ungaro, Annie Tran, DeAnn Maddox, Michael Haddox-Schatz, Ryan Bodenstein, Stephanie Vermeire, Casey Heck and Brita Hampton. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.
|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.|