Jefferson Lab Weekly Briefs June 23, 2010

Jefferson Lab Weekly Briefs
June 23, 2010

12 GeV Upgrade

Civil construction continues to make progress. On the North and South Access building additions, the transformers have been placed on the concrete pads, and the structural steel is set. Metal siding is being installed at the South Access building addition. At the South Linac service building, the contractor has started the ductbank for the power upgrade. On the Hall D Complex, the contactor has completed the Hall D concrete walls. These walls will be another 10 feet higher with structural steel framing. The contractor is also installing the under-slab grounding grid and plumbing at the Tagger Area.


The accelerator was running, with some interruptions. On Wednesday, ion pump 2L17B would not stay on, which caused two beamline valves to close. The faulty control board for the pump was replaced. Right after the ion pump issue was resolved, the underground fiber optics cable for the Personnel Safety System was damaged due to the construction work between the South Access building and the South Linac service building. More than 17 hours were lost due to this event. Some arc box supplies and beamline valve VBV3A03 also caused several hours of downtime. Over the weekend, beam delivery went well. On Monday morning, the accelerator finished the 5.056 GeV run. By Monday evening, the accelerator energy change (5.562 GeV) started.

Free-Electron Laser

The FEL group provided terahertz beam for a user, Harvey Rutt, of Southampton University in the U.K. The group is still preparing for ultraviolet lasing in July.

JLab's Safety Numbers

56 Days since Last Recordable Accident (JLab record: 331)
99 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

June 24: Lunchtime lecture and slideshow
July 5: JLab Closed: Independence Day holiday (observed)
July 19-21: JLab Facility Ops Review
July 28: American Red Cross Blood Drive




Environment, Safety, Health & Quality

Choking occurs when a foreign object, such as food or a toy, becomes lodged in the throat or windpipe, blocking the flow of air. Because choking cuts off oxygen to the brain, administer first aid as quickly as possible. If choking is occurring, the Red Cross recommends a "five-and-five" approach to delivering first aid:

  • Deliver five back blows between the person's shoulder blades with the heel of your hand;
  • Perform five abdominal thrusts (also known as the Heimlich maneuver).
  • Alternate between five back blows and five abdominal thrusts until the blockage is dislodged.

For additional information on assisting someone who is choking, visit The Mayo Clinic website.

Computing and Networking Infrastructure

Redhat Enterprise Linux Version 3 Support Ending
Redhat will stop support for the Redhat Enterprise Linux 3 version of its operating system in October. As a result, JLab will stop supporting RHEL3 on Oct. 1. If you are running a RHEL3 system, plan to upgrade to RHEL5 no later than Oct. 1. Installation CDs are available from the IT Division Helpdesk, which is open 8 a.m.-4:30 p.m., Monday through Friday. If you have questions about upgrading your system, contact the IT Helpdesk at x7155 or at


Personal Dosimeter Change-Out Set for June 30
The semi-annual personal dosimeter change-out will take place June 30. To ensure that your dosimeter is available for the change-out during this busy vacation, holiday and business travel season, everyone with a personal dosimeter is asked to place it in its assigned rack when not in use and especially before leaving the lab for an extended absence. If you have questions, contact Becky Mosbrucker, x7236.

A Grand Lunchtime Lecture and Slideshow
Bring your own lunch for "The Grand Canyon National Park," a lunchtime lecture and slideshow by Elliott Wolin offered in CEBAF Center room L104 at 12:30 p.m. on Thursday, June 24. In November 2009, Wolin and his wife hiked to the bottom of the Grand Canyon and camped there for three nights. In the presentation, Wolin will give a general overview of the geology of the Grand Canyon and discuss general backpacking concerns. The bulk of the presentation will be a slideshow of the trip. This lunchtime lecture is sponsored by JAG.