Jefferson Lab Weekly Briefs August 8, 2012
Jefferson Lab Weekly Briefs
August 8, 2012
12 GeV Upgrade
The fit-out of the Hall D complex with services and beamline items continues, with the cryogenics and solenoid magnet service module progressing well. The tagger magnet coils are being insulated and tested, with delivery expected in late summer. Wiring of the end-caps for the straw tubes for the Central Drift Chamber is well underway at Carnegie Mellon University. Construction of the fourth Forward Drift Chamber package (of four total) is underway onsite. The final Cockcroft-Walton high-voltage bases for the Forward Calorimeter are being assembled at Indiana University. The various readout boards for the Barrel Calorimeter are under production. Electronics procurements continue with the manufacturing contract awarded for several hundred FADC-125 read-out modules, and the contract for the F1TDCs is out for bid.
One of the critical activities for the Long Shutdown, the warm-up of the Central Helium Liquefier-1 and the CEBAF Linacs, began on Aug. 1. Things are progressing as planned, and the liquid helium has been transferred to storage to allow shutting down of the cold box. The Linacs are being warmed up in a controlled way to minimize the possible risks due to uncontrolled transients, such as the insulating vacuum pressure. So far, the linacs have been warming up in a controlled way.
Lots of activity is in progress in the tunnel enclosures and service buildings. The concerted effort by many groups necessary to undertake such a wide-scope shutdown should not be underestimated. Beyond the most visible components, such as cryomodules and magnets, there is an enormous scope of work in installation, survey and alignment, cabling, moving of stands, girders and equipment that is planned, coordinated and executed on a daily basis. CEBAF operations and the upgrade would not be possible without the expert and dedicated work of the support groups.
The FEL team concluded operations of the FEL for the calendar year on Aug. 1. This week, the team tested orbit lock software scripts from Colorado State University, performed some extended Terahertz experiments, and did more testing of the high dynamic range diagnostics. Substantial work is underway in reviewing the load lock and prep chamber design of the new gun. Two summer interns presented the results of their studies on the predicted vacuum level in the new gun and on PARMELA optimization of the new injector beamline layout.
Center for Theoretical and Computational Physics
The Collins effect contribution to the transverse single-spin asymmetry observed in the inclusive production of a single hadron in proton-proton interactions at large transverse momenta has been estimated using information from semi-inclusive deep-inelastic scattering and electron-positron data. The authors found that a sizable part of the asymmetry can be associated with the Collins effect, namely, a transversity function convoluted with the Collins fragmentation function. Future measurements at JLab with 12 GeV will pin down this contribution to high precision.
Facilities Management and Logistics
Electronic Forms Now Available for Property Storage Requests
JLab Calendar of Events
Aug. 6-10: 7th International Workshop on Chiral Dynamics
Environment, Safety, Health and Quality
While one may joke about not being able to walk and chew gum at the same time, being a distracted walker can have significant consequences. A number of JLab people have been observed in near-miss situations. While the walker may have the right of way on JLab streets, it does not prevent a person from being struck by a vehicle. Walk across JLab as you would drive on a highway – being especially careful in parking lots and crosswalks – and don’t become a distracted walker statistic.
Computing and Networking Infrastructure
Zimbra Calendar Testing
Zimbra Training Offered in August
Public Affairs Seeks Your Feedback on Newsletter
Ends Thursday: Last Chance to Order 2012 JLab T-Shirts or Sweatshirt
Quantities are limited, so be sure to order yours today!
Onsite TIAA-CREF Counseling Offered
Operational Safety Procedure Process Goes Electronic on Sept. 15
Department of Energy Sponsors Food Drive at JLab, Aug. 6-16
Onsite Blood Drive Set for Aug. 21
Studying the Quark-Gluon Plasma - Colloquium and Public Lecture
Tracking Thomas at JLab
Congratulations this week go to Saptarshi Mandal, who was the first to correctly identify the location for Aug. 1. Honorable mentions go to Michelle Shinn and Harry Fanning. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.