Jefferson Lab Weekly Briefs
August 19, 2009
12 GeV Upgrade
Construction of the Hall D Barrel Calorimeter detector is underway at the University of Regina in Saskatchewan, Canada. Production shipments of the Kuraray scintillating fibers are arriving according to schedule, and the first shipment of lead has been received and passed acceptance tests. Procedures for fabrication of the first article construction module have been finalized, and the base lead layer has been successfully glued to the aluminum base plate.
The Scheduled Accelerator Down ended on Aug. 17, with a lot of work done. Ops restored 5.97 GeV accelerator operation successfully over the weekend. Continuous wave beam (5 μA) was established to the beam switchyard dump. On Monday, the accelerator was scaled down to 5.764 GeV.
The FEL team had a successful week of operation devoted to beam measurements and optics characterization. Staffers also did some preparation for user runs on the Light Pseudoscalar and Scalar Search experiment by providing alignment beam to several labs and operating at secondary wavelengths.
A fully relativistic calculation of the polarized 2H(e,e'p)n reaction has just been performed <arXiv:0907.3712 [nucl-th]> at large Q2 in the impulse approximation, employing the Gross equation to describe the deuteron ground state and the SAID parametrization of the full nucleon-nucleon scattering amplitude to describe the final state interactions. The target spin asymmetries are shown to be sensitive to the full spin structure of the final state interaction. The results of this calculation are being used in support of the JLab E93-009 experiment in Hall B (EG1 run group).
JLab's Safety Numbers
35 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
Aug. 19: Jefferson Activities Group Luau
Environment, Safety, Health & Quality
Excessive heat exposure caused 8,015 deaths in the U.S. from 1979-2003. More people died from extreme heat in this period than from hurricanes, lightning, tornadoes, floods and earthquakes combined.
People suffer heat-related illness when their bodies can't properly cool themselves. The body normally cools itself by sweating; under some conditions, sweating isn't enough. As a person's body temperature rapidly rises, damage can occur to the brain and other vital organs.
To protect your health when temperatures are extremely high, remember to keep cool, use common sense and use the following tips:
For more information, visit the Centers for Disease Control "Extreme Heat" website.
Computing and Networking Infrastructure
Helpdesk Summer Hours Ending
Nuclear and Particle Physics at the Spallation Neutron Source
Register for a Personal Finance Lunchtime Seminar: Stretching Your Dollar
Public Tours Briefly Suspended
Remembering Camille 40 Years Later