Jefferson Lab Weekly Briefs November 9, 2011

Jefferson Lab Weekly Briefs
November 9, 2011

12 GeV Upgrade

The Hall D Civil construction contractor is finishing with balancing the air and water for the mechanical systems and commissioning to verify all mechanical and electrical systems are functioning according to the design requirements. On Nov. 3, inspections were conducted by representatives from the Architect-Engineering firm, Facilities Management, future Facility Users and the ESH&Q Division to establish the contract punch list. Upon completion of commissioning and safety-related punch-list items, a beneficial occupancy inspection will be conducted to turn the Hall D facilities over from the construction contractor to JLab. The beneficial occupancy date is anticipated to be toward the end of November.


The week began with turning on the radiofrequency (RF) accelerating cavities and magnet power supplies and letting them run at low levels after being off for several months. During the day, Engineering Support staffers worked on their respective systems, while at night, Operations staffers locked up the accelerator and sent the beam around as far as possible. After wrestling with vacuum valves that did not want to open and RF cavities that did not want to stay on, beam was sent halfway around the accelerator to the first first-pass (1R) dump on Thursday morning. Just before midnight on Thursday, one full pass of beam was sent around to the second first-pass (2R) dump. Four hours later, another pass was added, taking beam to the 4R dump. Friday saw many punch-list items taken care of, after which rethreading the beam around was rather difficult. Beam optics was cleaned up, but then an as-yet-determined problem with a magnet at the end of the fifth arc prevented achieving a third pass through the machine. The two-pass beam was subsequently steered to the beam switchyard, and 25 microamps of continuous wave beam was delivered to the BSY dump. The new 12 GeV C100 RF cavities were then turned on and run at a modest 10 Megavolts per meter, with > 40 uA beam; they performed superbly. The machine was in the process of being set up for beam breakup testing when the Arc #1 power supply failed at 1 a.m. Monday, effectively halting any further work with beam in the accelerator. In addition, the temporary shield wall for the Hall D tunnel was installed, which will allow running beam in the main accelerator during Hall D construction.

Theory Center

A collaboration between theorists and experimentalists has revisited the question of "How well do we know the neutron structure function?" The new analysis of inclusive proton and deuteron deep-inelastic scattering data included realistic uncertainties in the nuclear corrections to the deuterium data, from which neutron information is extracted. The uncertainties arise from the deuteron wave function, nuclear smearing and nucleon off-shell corrections. The analysis provides an important baseline that will allow future, model-independent extractions of neutron structure, such as those planned at JLab following the 12 GeV Upgrade, to be used to examine nuclear medium effects in the deuteron.


The Machine Shop is presently manufacturing components for the first of three SPX cryomodule cavity assemblies. Additionally, the shop is also manufacturing CRM crab cavities for Argonne National Lab. Work also continues on building the accelerator injector's positron spectrometer vacuum chamber. The shop has processed 160 job requests since Sept. 26.

The Alignment group has been busy aligning detectors and components in Hall C in support of the Q-weak experiment. The Region 2 and 3 detectors, the quartz bar detectors and the target have been aligned. Additionally, alignment determined the amount of fill that is covering the new tunnel leading to Hall D.

JLab Calendar of Events

Nov. 16 Colloquium and Public Lecture
Nov. 17: Quark Cafe's Thanksgiving Feast
Nov. 21: Safety Shoe vendor onsite
Nov. 24-25: Thanksgiving holiday; JLab closed
Dec. 2: Hall D Open House for Staff and Users
Dec. 5: Safety Shoe vendor onsite
Dec. 10: JAG Children's Holiday Party
Dec. 23-Jan. 1: Winter holidays/Shutdown days - JLab closed

Environment, Safety, Health and Quality

Reminder: Golf Carts Must Use Headlights After Dusk
Good safety practice calls for anyone at JLab using a golf cart between dusk and dawn to drive with the golf cart's headlights on. For some golf carts, turn on the headlights and enable the turn signals by turning the ignition key to the "accessories" notch.

Beware Glowing Eyes in the Headlights
Several herds of deer make their home in and around the JLab campus. The following are basic tips for safe driving near deer from the Insurance Information Institute:

  • Be especially attentive from sunset to midnight and during the hours shortly before and after sunrise, which are high-risk times for deer-vehicle collisions.
  • Deer seldom run alone. If you see one deer, others may be nearby.
  • When driving at night, use high-beam headlights when there is no oncoming traffic. The high beams will better illuminate the eyes of deer on or near the roadway.
  • Slow down and blow your horn with one long blast to frighten the deer away.
  • Always wear your seat belt. Most people injured in car/deer crashes were not wearing a seat belt.
  • If your vehicle strikes a deer, do not touch the animal. A frightened and wounded deer can hurt you or further injure itself.

Computing and Networking Infrastructure

JLab Primary Nameserver Work Set for Tomorrow
JLab's primary internal DNS name server will be taken offline at 7:30 a.m. for about five minutes on Thursday, Nov. 10.  There are continued issues with the primary nameserver, and this emergency effort will put in place a temporary nameserver until a complete solution can be implemented. Staff and users may see a slowdown in their internet connections during the work. If you have questions or concerns, contact the IT Division Helpdesk, x7155.


Quark Cafe Offers Holiday Desserts
The cafe is accepting holiday dessert orders through Nov. 18 during breakfast, lunch and Wednesday snack hours. The cafe is offering a selection of whole pies, including sweet potato, pumpkin, pecan, apple high and fruits of the forest. Pumpkin cheesecake is also available. Pre-ordered desserts will be available for pickup on Tuesday and Wednesday, Nov. 22-23. Pick up your order form and get more information in the Quark Cafe.

JLab Colloquium and Public Lecture Set for Nov. 16
Marc Kamionkowski, Johns Hopkins University, will present "The Cosmic Microwave Background: Beyond the Power Spectrum" in a colloquium set for Wednesday, Nov. 16 at 4 p.m. in the CEBAF Center auditorium. Kamionkowski will discuss new signatures in the cosmic microwave background.

Thanksgiving Warm-Up Buffet in the Quark Cafe
The annual Quark Cafe Thanksgiving Feast is set for Thursday, Nov. 17. This year's buffet will feature roast turkey with cornbread sage dressing, gravy, fresh orange-cranberry sauce, Smithfield ham, roast prime rib of beef with au jus and horseradish cream, Yukon gold garlic mashed potatoes, sweet potato casserole, green beans almandine, maple-walnut brussel sprouts, dinner rolls and assorted pies. The buffet is just $9.99 (plus tax).

JLab 2012 Holiday Calendar Posted
The official calendar of holidays to be observed by JLab in 2012 is now posted on the Human Resources page.

Mobile Mammography Unit Onsite Dec. 7
The Sentara Mobile Mammography Unit will be at JLab on Dec. 7. Mammography detects breast cancer, and The American Cancer Society recommends scheduling your first or baseline mammogram by age 40. It only takes 15 minutes! This service is open to all; personal health insurances will be billed. To make an appointment, visit

Tracking Thomas at JLab
Little Thomas is visiting all corners of the JLab campus. If you can identify his location this week, email Kandice Carter with your guess. Guesses are accepted through Friday.

Congratulations this week go to Doug Higinbotham, Jason Willoughby, Russell Mammei, Michelle Shinn, Mike Wilson, Narciso Gomez, Christine Fragapane and Samika Hawkins, who were the first to correctly identify the Nov. 2 location. Honorable mentions go to Deborah Dowd, Harry Fanning, Sue Witherspoon, Ron Bartek, Jim Boyce, Karsten Flowers, Dick Owen and Stephanie Vermeire. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.