Jefferson Lab Weekly Briefs August 18, 2010

Jefferson Lab Weekly Briefs
August 18, 2010

12 GeV Upgrade

There is a great deal of 12 GeV civil construction activity in progress. In the accelerator tunnel, installation of the low-conductivity water (LCW) header pipe for the 10th arc commenced with the start of the summer Scheduled Accelerator Down. At the North and South Access Building additions, the sitework is being completed with asphalt paving. At the Central Helium Liquefier (CHL) building addition, the underground portion of cooling water piping for the CHL #2 compressors is being installed from the cooling towers to the west end of the new addition. Also, SEG blocks for the Hall D photon beam dump and electron beam dump are being transported to the Hall D construction site. The concrete roof for the Hall D truck ramp has been placed.


Hall B has successfully completed a major data-taking run: g9b. A total of 15 billion events were collected using the excellently performing polarized frozen spin target, "FROST." This marks a huge milestone of the N* program with CLAS: For the first time, data collection for several "complete experiments" has been finished. It requires the measurement of meson production with unpolarized, circular and linearly polarized photons, as well as transverse and longitudinally polarized targets, and the measurement of recoil polarization of baryons. As a minimum, eight independent measurements are needed. CLAS has obtained 16 measurements for some channels. The combination of previous run groups and the current run group has finally achieved this goal. "Complete measurements" allow the experimenters to determine the production amplitudes for pseudoscalar meson photoproduction in a truly model-independent way, the Holy Grail of N* physics for the past 35 years, when the corresponding theory paper by Barker, Donnachie, and Storrow appeared in Nucl. Phys. B95, 1975.


Operations began the week delivering beam to the halls. On Thursday, the injector was commissioned with higher gun voltage. The commissioning went well, with gun2 voltage raised from 100 to 130 kilovolts. The higher voltage will make high-current beam transport better. Hall C received beam with gun2 at 130 kV. At 7 a.m. on Friday, the spring run ended successfully and the Scheduled Accelerator Down started.

Free-Electron Laser

Last week's efforts were focused on installation of the final components required for turn-on of the ultraviolet FEL. After considerable exemplary effort by many FEL staff members, the final required hardware components (wiggler chamber, the optical cavity mirror metrology system, viewers, beam position monitors, optical diagnostics and controls) are in place and pumped down. The rapid progress and successful completion of this work is another indication of the dedication and enthusiasm of all involved.

JLab's Safety Numbers

33 Days since Last Recordable Accident (JLab record: 331)
155 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

Aug. 20: Safety Shoe Vendor onsite
Aug. 23-25: PAC 36
Sept. 1: TEDF Groundbreaking Ceremony
Sept. 6: Labor Day holiday - JLab closed
Sept. 7: Safety Shoe Vendor onsite




Computing and Networking Infrastructure

CNI Systems Maintenance: Aug. 24, 5-10 p.m.
The CNI group is planning a systems maintenance period on Tuesday, Aug. 24, from 5-10 p.m. During this maintenance, there will be intermittent network outages as network switches receive code updates. This will include a brief internet outage, as well. Additionally, the systems that provide the web search function will be replaced, causing a short JLab webpage search outage. The current web server will also be updated.

Shutdown of wireless network 'jlab_secure' on Aug. 24
Wireless network 'jlab_secure' will be turned off on Tuesday, Aug. 24. If you are still connecting to 'jlab_secure,' you will need to migrate to wireless network 'jlab' at your earliest convenience. If you have any problems connecting to 'jlab,' contact the IT Helpdesk at x7155.

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


Lost and Found Online
On Aug. 11, two brass keys were found near a door to the CEBAF Center F Wing and were turned in to Lost and Found. The keys are each about 1.5 inches long and appear to be for a locker or door lock. They are held together with a clip to a small, white, plastic, square tag with a notch in it. The numbers 650 or 250 and 202 appear to be written in black marker on one side of the tag. The keys do not appear to belong to any JLab key lockbox. If these keys are yours, stop by the CEBAF Center front desk to claim them. This and other Lost and Found items are posted on JLab’s Classified Marketplace page, which is linked on Insight.

Onsite TIAA-CREF Counseling Offered
TIAA-CREF will offer individual counseling sessions onsite on Aug. 24, Oct. 28-29 and Dec. 16-17. In these sessions, employees can discuss their personal financial situation with a TIAA-CREF consultant on a confidential basis. To discuss your plan and options for managing your retirement savings or to schedule an appointment with a TIAA-CREF individual consultant, call TIAA-CREF at (800) 732-8353, M-F, from 9 a.m.-8 p.m.

Construction & Maintenance Recyclables Are Hot Commodities
Thefts of copper and other metals from utilities, contractors and home owners have been on the rise in Newport News, resulting in the loss of thousands of dollars and increased costs of doing business. At JLab, project managers and contracting officials should advise companies and workers that metal scrap collection for personal use is not permitted in any form. All excess JLab metals should be placed in metal recycling containers in the JLab Central Material Storage Area. Persons who remove materials from collection containers without permission may be disciplined, prosecuted or barred from entering JLab. You can help deter theft by storing materials in an appropriate manner, disposing of materials in JLab recycling containers, and reporting suspicious persons and activities to JLab security at x5822. If you have questions or concerns, contact Kris Burrows at x7548 or Mike Lewellen at x7169.

JLab Strategic Plan Available Online
The JLab Strategic Plan is now available for review online. The document has been posted to the Insight page in the Popular Applications portlet.

American Red Cross Blood Drive Results
The July 28 blood drive was very successful. A total of 61 people signed up to donate blood. Several people were deferred for various reasons; however, the Red Cross still collected 52 pints of whole blood and two donations of red cells using the Double Red process, exceeding the lab goal of 45 units! JLab donors made a significant contribution to the American Red Cross. Occupational Medicine staffers extend a sincere thank you to everyone that participated with this blood drive and congratulations for a job well done!

United Way School Tools Drive Underway
Collection boxes for donations of new school supplies are in Building 85, and in the CEBAF Center, VARC and ARC lobbies. School supplies for students of any grade level may be placed in the boxes and will be collected until close-of-business Tuesday, Aug. 31. Appropriate items include: pens, pencils, student scissors, crayons, spiral notebooks, 3-ring binders, binder paper, pocket folders, rulers and protractor/compass sets. The United Way will collect and disburse the materials to area schools. For more information, e-mail or call Joshua Cameron at x7628.