Jefferson Lab Weekly Briefs November 18, 2009

Jefferson Lab Weekly Briefs
November 18, 2009

12 GeV Upgrade

The July 2010 scheduled accelerator down is the last scheduled shutdown prior to the six-month down planned for 12 GeV installation starting in May 2011. In order to coordinate with the scheduled electrical outages during the July 2010 down, JLab Facilities Management personnel have added two acquisition packages for civil construction procurements to their FY10 plans. The N&S Linac Power Upgrade, moved ahead from FY11, provides two new 1.5 MVA unit substations – one each at the North and South Linac service buildings to provide power for the new radiofrequency zones for the 12 GeV cryomodules. The new switchgear section, previously part of the FY10 Central Helium Liquefier Utility Upgrade contract, will distribute power to the new 5 MVA unit substations for the CHL #2 compressors.


Overall, the accelerator ran well. During the past week, the experts spent more than two shifts troubleshooting high Hall A Compton noise. The injector was optimized and the Compton counts were much improved. On Thursday, the storm caused a power glitch, which led to a couple of hours of downtime during the swing shift.

Free-Electron Laser

This week, FEL staff performed several tests of the optical transport and setup at long wavelengths and continued studies on injector optimization and terahertz, despite minor water seepage in the vault due to November Nor'easter downpours. The team held a planning meeting for actions on the injector during the December-February time frame when the FEL will not be running. FEL staffers have been heavily engaged with the JLAMP proposal, and tasks, responsibilities and timelines have been determined.

Theory Center

A collaboration between Theory Center staff and experimental and theory users from Hampton University and elsewhere has completed a new global analysis <arXiv:0911.2254 [hep-ph]> of quark distribution functions in which the usual kinematical cuts are relaxed, thereby including more data at high values of Bjorken-x. Effects of target mass (TM), higher twist and nuclear corrections are significant at large x, but the extracted distributions are stable to TM model variations as long as higher twists are also included. The behavior of the d quark as x->1 is particularly sensitive to the nuclear corrections, and using realistic nuclear smearing models, the d-quark distribution is found to be smaller at large x than in previous fits with more restrictive cuts.

JLab's Safety Numbers

126 Days since Last Recordable Accident (JLab record: 331)
434 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

Nov. 23: Colloquium - State of High-Level Waste and Spent Nuclear Fuel Disposal, CC auditorium, 4 p.m.
Nov. 26-27: Thanksgiving holidays - JLab closed
Dec. 5: JLab Children's Holiday Party
Dec. 10: Safety Shoe Vendor onsite
Dec. 24 - Jan. 1: Winter holidays/Shutdown days - JLab closed




Environment, Safety, Health & Quality

Slips, Trips and Falls
Falls account for about 15 percent of all work-related injuries. Falls often occur at ground level because of slippery surfaces caused by grease, water or ice. Even if you have a sturdy, slip-resistant floor, a slight contamination from dust, water, grease or metal shavings can make the surface slippery. The use of inappropriate footwear, poor lighting and obstacles in walkways and on stairs can also contribute to slips, trips and falls. Elevated falls account for about 25 percent of all falls: on average about one quarter of all elevated falls are from ladders, while another quarter are from elevated vehicles and other mobile equipment. Same-level falls account for the remaining 75 percent. A few reminders:

  • Look out for foreign substances on the floor. Watch for liquid spills such as beverages, food, grease, oil, soap or debris. Even small quantities of these substances, sometimes almost too small to see, can be slippery.
  • When you come into a work area from outdoors in rainy weather, wipe your shoes thoroughly on a doormat. This isn't just to keep the floor clean, it also prevents the wetness of your shoes from making you slip and  fall.
  • Always try and wear the best non-skid shoe possible, especially during bad weather. Shoes that have worn, smooth soles should not be worn. Avoid high heals during inclement weather. Select something that has a large surface area, which has good traction.
  • Use handrails especially during inclement weather, and if there is not enough light, please report it. Stairwells are to be kept uncluttered, with some sort of non-slip coating applied to the steps. Inform your supervisor if you notice a step that is slick. Don’t carry objects up or down steps that may obstruct your view.

To report unsafe surfaces at JLab, call x7400. Also contact your area Safety Warden so that others in the are may be warned.


Performance Appraisals
The deadline for all appraisals to be completed and presented to employees is only a month away. With the Thanksgiving holiday coming, that leaves less time than one might think. To obtain a PIN to work offsite or get answers to questions that may be holding you up, contact Bruce Ullman at x7170 or Cassandra Andrews at x7068.

JLab 25th Anniversary Jacket Liners
If you are interested in ordering a liner for your 25th Anniversary Jefferson Lab Jacket, please contact Michelle Lechman, Public Affairs at The deadline for signing up is Monday, Nov. 23.

Food Drive for Foodbank
The JAG is sponsoring a food drive through Nov. 20 to support the Foodbank of the Virginia Peninsula. Especially needed are peanut butter, nuts, dried fruit, canned meats and tuna, canned vegetables, cereal, crackers, rice and chunky soups. No perishable food items or food in glass or breakable containers will be accepted. Drop barrels have been placed in CEBAF Center, the MCC, Test Lab, VARC and ARC.

Quark Cafe Offers Thanksgiving Feast
Quark Cafe staff will host a Thanksgiving Buffet from 11:30 a.m. to 1:30 p.m., Thursday, Nov. 19. For $8.99, patrons get the buffet spread, which includes one plate, a 24 oz. fountain drink and a dessert. The buffet will feature buttery sage and thyme-roasted turkey with home-style gravy, carved Smithfield ham, roasted duck with wild mushroom demi-glaze, maple-roasted glazed butternut squash, fresh herb dressing, green beans almandine, Yukon gold smashed potatoes, sweet potato casserole, fresh cranberry relish, dinner rolls and a selection of scrumptious desserts.

Holiday Desserts to Tempt Your Taste Buds
The Quark Cafe is now taking Thanksgiving dessert orders. Selections include apple, pumpkin, pecan and sweet potato pies and pumpkin cheesecake. The deadline for orders is 2 p.m. on Friday, Nov. 20. Order forms and a full list of desserts are available in the cafeteria.