Jefferson Lab Weekly Briefs October 26, 2011

Jefferson Lab Weekly Briefs
October 26, 2011

12 GeV Upgrade

At the request of the Office of Nuclear Physics, Daniel Lehman, Director of the Office of Project Assessment in DOE's Office of Science, convened a team of 24 experts plus 10 observers in an Independent Project Review of the 12 GeV CEBAF Upgrade Project held Oct. 18-20 at JLab. The purpose of the review was to assess progress in all aspects of the project. The review committee commented on the excellent progress made over the last year, with strong support from the lab in all areas. Twelve recommendations were provided to guide activities in the coming months.

Refinement of the low-level radiofrequency control system continues. Checkout of the second 12 GeV cryomodule, C100-2, is almost complete. The third 12 GeV cryomodule has been completed and moved to the Cryomodule Test Facility. Three more are being assembled. JLab personnel witnessed testing of the first-article box supply at the vendor’s facility. Assembly of the third new RF zone is nearly complete.


In Hall C, the High-Resolution Kaon Spectrometer has been fully disassembled and relocated to the Experimental Staging Building. Hall C staff, JLab staff and the Q-weak collaboration are engaged in final preparations for the resumption of the Q-weak experiment in November. The Moller polarimeter has been repaired and the beamline in the area of the polarimeter is under vacuum. The Q-weak liquid hydrogen target underwent a successful cool-down test and has been surveyed into position. New beam current monitors have been installed on the beamline. These monitors, when coupled with the new BCM electronics, will minimize the contribution of current measurement noise to the error on the measurement of Q-weak. A sieve slit has been installed in region I of the Q-weak setup in order to enhance tracking mode measurements.


Radiofrequency commissioning of SL25 continued. The dipole power supply for the spectrometer magnet at 0L07 was replaced. Radiation measurements at the northeast stub gate were performed with beam in the 0L07 spectrometer dump and later with north linac RF on; radiation levels remained at background for both instances. During the evening shifts, the injector was set up for upcoming low-energy beam breakup studies. Afterward, work on the injector laser table was performed by Q-weak personnel; later in the week, Q-weak performed studies with beam in the injector.  The area in the northeast spreader region damaged from the overheated magnets was cleaned up. The damaged magnets were removed for later replacement with spares. Beam instrumentation and beam loss sensors in the area were checked out, with some replaced purely as a precaution. Operations staff began turning on the north and south linac RF cavities to verify operation.

Theory Center

A new theory paper explores the sensitivity of W and Z boson production in hadronic collisions to uncertainties in parton distribution functions (PDFs) at large momentum fraction x, showing increasing effects at high boson rapidities, particularly for the d quark. The effects of PDF uncertainties on heavy W' and Z' bosons beyond the Standard Model become progressively more important for larger boson masses, in both proton-proton collisions at the LHC and in proton-antiproton scattering at the Tevatron. The PDF uncertainties at large x will be reduced with new data from deep-inelastic scattering measurements at JLab following the 12 GeV Upgrade.


The Electrical Support Groups have been busy performing checkout of magnet, RF and Instrumentation & Controls systems in preparation for resuming accelerator operation. Initial power up and interlock checks are performed prior to full operational restoration. Problems have been encountered with RF loads and magnet ground isolation issues that have required significant effort to rectify. Diagnostic and vacuum restoration activities have gone better, with most equipment being restored without major problems. Work on the 12 GeV RF system commissioning and installation has continued in parallel with the recovery work. Two of the new RF systems are being prepared for beam testing during start up and hopefully will run in support of the upcoming Physics program. Gaining operational experience now with the new RF systems will greatly enhance the 12 GeV accelerator start up following the next long shutdown.

Environment, Safety, Health and Quality

Halloween Safety Tips
With little ghosts and goblins set to hit the streets next week for Halloween, now is a good time to review basic fright night safety information for homeowners, parents and little ones:

  • Make sure your walkways are adequately lighted and clear of all tripping hazards;
  • Put pets in a secure area where they can't get loose and freak out, or be freaked out by, trick-or-treaters;
  • Make sure all costumes are made of flame-resistant materials;
  • Trick-or-treaters should carry a flashlight, light stick or reflective material;
  • Young trick-or-treaters should always be accompanied by an adult;
  • Drivers should be cautious of trick-or-treaters and vehicles that may make frequent stops or turns;
  • Be aware of the trick-or-treat times set for your neighborhood.

Additional Halloween safety tips can be found online at, the Consumer Product Safety Commission website and the Halloween Safety website. For non-trick-or-treating Halloween celebration ideas, see the Travel Virginia website and the local events calendar.

Computing and Networking Infrastructure

Major Systems Outage on Friday, Dec. 23
The CNI group is planning a major computer systems outage for the first day of this year's winter holiday break. On Friday, Dec. 23, 6 a.m.-5 p.m., all major systems will be unavailable, including email, calendar and access to central file services, such as the J:, K:, L: and M: drives, home directories, group areas, etc. Additionally, all MIS applications and business services applications will be unavailable. All services will return to full operation by 5 p.m. For additional information, contact the IT Division Helpdesk, x7155.


JLab Beam Kickoff and Tailgate Party
The Jefferson Activities Group invites staff, students and users to celebrate JLab's successful Six-Month Shutdown and the work underway to resume CEBAF accelerator operations. The picnic will feature chili, Brunswick stew, nachos, hot dogs, hamburgers and hot cocoa, as well as a craziest fan contest and informal games. Wear your favorite team jersey to the picnic next Wednesday, Nov. 2, 3-5:30 p.m. on the SURA Residence Facility field. Volunteers make JAG events possible, so click the link to volunteer your time so that everyone can have a safe, fun and festive party.

Annual E-Commerce Small Business Vendor Show
The vendor show will take place 9 a.m.-2 p.m. on Thursday, Nov. 3, in CEBAF Center. If you purchase products for use at JLab, come on out to enjoy a continental breakfast and noontime snack as you peruse featured products offered by JLab's vendors to help make your and your colleagues' work safer, faster and easier.

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 DeAnn Maddox, Karen Bartek, Michael Wilson, Mike Martin, Rochard Jacobsen and Narciso Gomez, who were the first to correctly identify the Oct. 19 location. Honorable mentions go to Brita Hampton, Sam Holben, Greg Adams, Dick Owen, Jason Willoughby, Doug Higinbotham, Michael Haddox-Schatz, Cindy Eller, Lisa Surles-Law, Guy Wilson, Jim Follkie, Harry Fanning and Dena Polyhronakis. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.

JLab Calendar of Events

Nov. 1: Science Series public lecture
Nov. 2: JAG Beam Kickoff Tailgate Picnic
Nov. 3: Annual E-Commerce Small Business Vendor Show
Nov. 6: Daylight Saving Time ends
Nov. 7: Safety Shoe vendor onsite
Nov. 24-25: Thanksgiving holiday; JLab closed