Jefferson Lab Weekly Briefs January 11, 2012

Jefferson Lab Weekly Briefs
January 11, 2012

12 GeV Upgrade

The Hall D Complex facilities have been accepted from the construction contractor. Approval for occupancy of the Counting House, Service Building and Tagger Area is expected to happen in a few weeks, following completion of various tasks related to safety and janitorial services.


In Hall C, the Q-weak experiment resumed data taking, starting with yield measurements on a dilute gas in the target cell to determine the target cell window thicknesses. The experiment is now part way through the low current tracking measurements that are used to determine the experiment kinematics. Once these are completed, Q-weak will return to asymmetry measurements at the maximum possible beam current. During the last week, the laser for the Compton polarimeter was repaired, and a burst water-cooled power lead (connecting the Qtor magnet and power supply) was replaced. The Hall C Users meeting is set for this Friday and Saturday, Jan. 13-14, in CEBAF Center Room F113.


Last week was dominated by restoration of the accelerator and the halls following the break. Radiofrequency recovery included the repair of many cavities in the period between the termination of beam in December and the beginning of the winter down. This allowed the accelerator to be configured to the same energy with fewer passes, a necessity for the present lineup of hall experiments. Injector studies were performed in support of the Hall C Q-weak experiment. C100 studies continued during beam studies. Low-conductivity water leaks in both the accelerator and the halls required an interruption of beam delivery to repair. Tuesday beam studies time was used to swap LCW pumps in the end stations and to improve beam optics to Halls B and C. Higher-pass beam optimization, necessary for future running with Hall A, was also performed.

Theoretical and Computational Physics

In a recent Theory Center paper, the evolution of transverse momentum dependent distributions (TMDs) is applied for the first time to observables. The Sivers transverse single spin asymmetry is calculated and compared at different scales using the TMD evolution equations applied to previously existing extractions. Recent COMPASS measurements from CERN are shown to be consistent with the suppression prescribed by TMD evolution, and some predictions are given for future experiments.


The Machine Shop is presently manufacturing or continuing to manufacture:

  • Components for the second and third SPX cryomodule cavity assemblies,
  • CRM crab cavities for Argonne National Lab,
  • CLAS 12 HTCC mold mirror facet block 4 for Hall B,
  • Two beam transport insertable dumps for the 12 GeV Upgrade,
  • Six CRM C100 cryomodule waveguide knife flanges (reworking),
  • One BL OR02 SLM vacuum chamber and one dipole vacuum chamber for the 12 GeV Upgrade.

The shop has processed 200 job requests since Nov. 7.

JLab Calendar of Events

Jan. 16: Martin Luther King Day holiday - JLab closed
Jan. 23: Safety Shoe vendor onsite
Jan. 24: Science Series Lecture - Volcanoes in Virginia
Jan. 27: American Red Cross Blood Drive
Feb. 4: Va. Regional High School Science Bowl
Feb. 7: Science Series Lecture: Living and Working in the Freezer

Environment, Safety, Health and Quality

Electrical Safety
Every year, electrical products are associated with injuries, deaths and fires in homes. The U.S. Consumer Product Safety Commission staff recommends inspecting electrical products in your home every six months. Each time you change your clocks, or whenever you move to a new home, it is the perfect time to check your smoke alarms and perform a check of your home's electrical devices on this U.S. CPSC free home electrical safety room-by-room checklist.

Computing and Networking Infrastructure

CNI Maintenance Day Set for Tuesday, Jan. 17, 5-7 p.m.
The CNI group is planning a mini-maintenance period on Tuesday, Jan. 17, 5-7 p.m. During this time, patches will be released for both Windows and Linux desktops. Plan to reboot your Windows or Linux desktop on Wednesday morning to finalize patch installations. If you have questions or concerns, or any time you experience a problem with your computer, contact the IT Division Helpdesk, x7155.

Brief Phone Outage Scheduled for Thursday, Jan. 12, 5-5:30 p.m.
There will be a brief network/phone outage at 5 p.m. this Thursday for the Test Lab (Bldg. 58), RadCon complex (Bldgs. 52/52b/52c) and Bldgs. 59, 34d, 34e. All services should be back online by 5:30 p.m. If you have questions about the outage, contact the IT Division Helpdesk, x7155.


Science Series Lecture: Volcanoes in Virginia!
Everyone is invited to the next Science Series lecture, set for 7 p.m. on Jan. 24 in the CEBAF Center auditorium. The recent earthquake may have you wondering what other surprises Virginia's geology may hold. Could there be a volcanic eruption in Virginia? According to Dr. Elizabeth Johnson, James Madison University, a number of mysterious eruptions occurred in western Virginia 35-48 million years ago. This talk investigates the possible origins of these eruptions, and what they can tell us about the crust and mantle underneath Virginia. All Science Series lectures are free and open to students and adults with an interest in science.

New Dog Training Class Forming
About 96 percent of dogs who end up in shelters with behavioral problems have not received any obedience training, according to a recent study in the Journal of Applied Animal Welfare Science. JLab staff, users and their family members can beat the statistic by joining the JAG Dog Training Club. A new Canine Good Citizen/Therapy Dog class is starting on Tuesday, Feb. 7 at 7 p.m. in the VARC lobby. Dogs who attend this class must be at least six months old, housebroken and up-to-date on all shots. For more information, contact Joyce Miller, x7163, or Brian Kross, x7022.

Onsite Blood Drive Set for Jan. 27
The next American Red Cross Blood Drive is scheduled for Friday, Jan. 27, 10 a.m.-4 p.m. in CEBAF Center Room F113. New and repeat donors are encouraged to attend. Appointments and walk-ins are welcome. Contact Johnie Banks, x7539, to schedule an appointment.

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 Karl Slifer, Samika Hawkins, Harry Fanning, Jim Follkie and Doug Higinbotham, who were the first to correctly identify the Jan. 4 location. Honorable mentions go to Ryan Bodenstein, Pashupati Dhakal, Mike Dickey, Dick Owen, Mike Martin and Michelle Shinn. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.