Jefferson Lab Weekly Briefs July 21, 2010


Jefferson Lab Weekly Briefs
July 21, 2010

12 GeV Upgrade

Civil construction for the 12 GeV Upgrade is now 25 percent complete. The North and South Access Building additions have taken shape, with the structural steel and metal siding installed. At Hall D, the last 10 feet of the walls is being framed with structural steel. A portion of the concrete floor for the tagger area has been placed and the contractor is installing the reinforcing steel for the remaining portion of the concrete floor. The contractor for the Central Helium Liquefier (CHL) utility upgrades has mobilized and the new transformer and switchgear at the South Linac is being installed.


In Hall C, installations of the Q-weak experiment, upgraded beamline and high-power cryotarget are complete. Preparations for helium and hydrogen cool downs of the target are underway and will be followed by tests with beam. The first beam in eight months was recently delivered to Hall C. This low-current beam was used for the initial checkout of Q-weak detectors and the new beamline.


This past week, the accelerator was up and beam available but none of the experimental halls took beam. Hall A started the summer down for installation. Hall B was down due to issues with its target, and Hall C was down, because work on the Q-weak target was not complete. The accelerator was used for beam studies and measurement of the quality factors of the cavities. The CHL tripped Saturday and was quickly recovered.

Free-Electron Laser

The FEL team continues to make progress toward ultraviolet lasing, although issues with the wiggler chamber welding have led to a slip to the third week of August for first try at oscillation. The team did complete the optics installation and  verified that instrumentation works properly. The FEL hosted a visit by two DOE Basic Energy Sciences program managers for a tour of the FEL and discussions on accelerator R&D.

Theory Center

Several experiments aimed at studying parity violation in low-energy processes involving few-nucleon systems are being completed or are in an advanced stage of planning at cold neutron facilities (LANSCE, NIST and SNS), with the primary objective of determining the fundamental parameters of hadronic weak interactions (HWI), in particular the strength of their long-range component mediated by one-pion exchange. The determination of these parameters requires evaluating matrix elements of HWI operators between eigenstates of the strong-interaction Hamiltonian and, as a result, experiments in this field are especially reliant on theory for their analysis and interpretation.  A new paper <arXiv:1007.2052> provides a detailed theoretical study of the (parity-violating) longitudinal asymmetry in the charge-exchange reaction 3He(?n,p)3H (whose measurement is being planned at the SNS), based on state-of-the-art interactions and wave functions.

Facilities Management and Logistics

Site Construction Updates


  • The EEL Parking Lot will close at 5:30 p.m. today for striping. All vehicles and stored materials/equipment must be removed.
  • Rattley Road will close at 5:30 p.m. today for striping. Subcontractors will also finish painting the crosswalk on Hadron Drive.
  • On the accelerator site, travel on CEBAF Blvd. will be restricted to one lane south of the Guard House for installation of an electrical ductbank July 22-26. Flagmen will be present to assist vehicles.
  • The CEBAF Center parking lot is now striped and all striped areas are open for parking.


Note that all road and parking lot striping work is weather dependent. If it rains during the scheduled work period, the work will be rescheduled.




Environment, Safety, Health & Quality

Back injuries are a leading cause of lost work time. The types of back injuries include: strains, sprains, bulging and herniated disks. Remember to protect your back by:

  • Maintaining good back posture
  • Exercising regularly
  • Using available lifting equipment and have a lifting plan
  • Using your legs; bending them when lifting
  • Always thinking about your back before using it to lift


You can consult with Industrial Hygiene (Dick Owen, x6381) regarding exposure to workplace hazards and Occupational Medicine (Johnnie Banks, x7539) regarding your working conditions. Occupational Medicine staff may be scheduled to conduct an ergonomic assessment for you. Together, Industrial Hygiene and Occupational Medicine can recommend improvements that will make your work-life safer and healthier.

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


American Red Cross Blood Drive
The next American Red Cross Blood Drive is scheduled for Wednesday, July 28, from 10 a.m.-4 p.m. in CEBAF Center room F113. New and repeat donors are encouraged to attend. Walk-ins are welcome; however, making an appointment allows the Red Cross to schedule adequate staff for the visit. Volunteers are also needed to help with the blood drive. To schedule an appointment or to volunteer, e-mail or call Johnie Banks, x7539.

August Beam Physics Symposium Honors Yaroslav Derbenev
On Aug. 2 and 3, Jefferson Lab will host an international event to celebrate a milestone for both a scientist and his half century in science. The lab is holding a Beam Physics Symposium to honor the 70th birthday and lifetime of achievements in accelerator and beam physics of Yaroslav "Slava" Derbenev, whose distinguished career stretches from Novosibirsk to Yerevan and from Ann Arbor, Mich., to JLab's Center for Advanced Studies of Accelerators. A special session recognizing Derbenev will take place from 4-5 p.m. on Aug. 2 in the CEBAF Center auditorium. The entire JLab community is invited to this portion of the symposium. For more information, contact Audrey Barron, x7327, or Yuhong Zhang, x7509.

New SOTR Training And Certification Process
JLab's Subcontracting Officer's Technical Representatives (SOTRs) handle a wide range of contract management responsibilities, providing oversight on everything from ensuring that the subcontractor is complying with JLab policies to monitoring work progress. To help prepare SOTRs for their responsibilities, the Procurement Department has instituted a training class and a certification process for all current and new SOTRs. The class, GEN020 SOTR Training, is offered on the last Wednesday of every month, from 8:30 a.m. to noon in ARC 428. Current SOTRs have one year to complete the process, while new SOTRs must do so before assuming their duties. You can sign up for the class online through the Training and Development webpage.

JLab's Safety Numbers

84 Days since Last Recordable Accident (JLab record: 331)
127 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

July 28: American Red Cross Blood Drive
July 23: Safety Shoe Vendor onsite
July 30: Science Education Summer Poster Session
Aug. 23-25: PAC 36
Aug. 5: Safety Shoe Vendor onsite
Aug. 20: Safety Shoe Vendor onsite
Sept. 1: TEDF Groundbreaking Ceremony
Sept. 6: Labor Day holiday - JLab closed