Jefferson Lab Weekly Briefs April 18, 2012

Jefferson Lab Weekly Briefs
April 18, 2012

12 GeV Upgrade

In response to the reduced FY12 budget and subsequent extended duration of the long shutdown, the 12 GeV team has updated the FY12/13 installation schedules. These have been integrated into the lab-wide shutdown schedule. As installation activities increase in the completed 12 GeV conventional facilities, weekly meetings with Facilities Management & Logistics ensure coordination of resources. The 12 GeV team is working with FML to finalize all transportation, material handling, space, storage and waste/recycle needs.


In Hall A, the g2p experiment has been in a smooth production mode this week. The experiment has completed data collection for several kinematics at the 1.7 GeV energy setting.

In Hall C, the Q-weak experiment has completed most of a measurement of the parity-violating asymmetry of the nucleon to delta transition using a beam energy of 877 MeV. The measurements consist of high-current measurements on hydrogen and aluminum targets, as well as a set of low-current tracking measurements to define the kinematics.

Voting in Users Group Elections Open Through April 30
The annual election for new members to the JLab Users Group Board of Directors (UGBoD) is underway. This body represents all the researchers who use Jefferson Lab facilities – to the lab and the world at large. Biographical sketches of the candidates can be accessed through the ballot page. The election will close at 5 p.m. EDT on Monday, April 30. Newly elected members will be announced at the 2012 Users Group Meeting, and their terms will begin after the meeting.


The accelerator energy was changed and hall passes were reconfigured. Problems with capture resulted in a lost shift. Once that was repaired by the Electrical Engineering Support group, the machine ran well, with virtually uninterrupted beam to all three halls for the rest of the week. Over the weekend, Hall C vacuum degraded, but no specific cause could be found. Various beam currents were sent and pumps and instrumentation were investigated. The cause of the vacuum problem is still under investigation.

Free-Electron Laser

This week, FEL Operations staffers supported experiment LOP 12-008, 2.2 Micron Lasing Performance, during the day shift. The team delivered several kilowatt hours of FEL light at wavelengths between 2.14 and 2.25 microns in order to characterize a new set of optics. In the evening, the machine was used for a terahertz experiment, LOP 12-010. Machine utilization has been exceeding 16 hours per day during the week, with machine maintenance occurring on third shift and the weekend. The FEL team plans to continue operating two shifts per day until moving to ultraviolet lasing setup in a week.

Center for Theoretical and Computational Physics

In a recent paper, the scattering phase shifts for the spin-singlet and spin-triplet neutron-Σ¯ systems have been obtained from lattice QCD. The calculations, performed at a pion mass of mπ ~ 389 MeV in two large lattice volumes, and at one lattice spacing, are extrapolated to the physical pion mass using effective field theory. The low-energy neutron-Σ¯ interactions determine, in part, the role of the strange quark in dense matter such as neutron stars, and the results obtained in this calculation strengthen theoretical arguments that the strange quark is a crucial component of dense nuclear matter.


The lab's new CAD and data management software tools, NX and Teamcenter, are in the process of being rolled out across all mechanical design groups. Training for both NX and Teamcenter will be held in April. In the future, it is expected that Teamcenter's role will expand to handle additional documents and engineering data beyond CAD models and drawings.

In addition, electronic signature for CAD drawings, procedures and specifications is in the beta test stage. E-sign will enable drawing/document owners to get signatures without having to print out vellum drawings to carry around for manual signatures. The resulting savings will be in reduced paper usage and a more efficient signature process.

Environment, Safety, Health and Quality

Protective Footwear
According to the U.S. Department of Labor's Bureau of Labor Statistics, there were nearly 100,000 foot injuries on the job in 2010 that caused workers to miss work. This number indicates how important it is to procure and wear the proper type of protective footwear or safety shoes when working in areas that require protective footwear.
Protective footwear is tested with a number of criteria (and not all criteria apply to every type), such as impact and compression, puncture, heat, cuts, electrically conductive, static and traction. Other factors include specific applications to address wet conditions (waterproof) and temperatures (hypothermia and freezing or high-heat applications). You need to inform the safety shoe vendor of the type of work environment you are in and the type of hazards, so they can help you select the appropriate shoe and material.

Footwear is also identified under ANSI standards as to whether it is for a male or female. Often women select a shoe from the appropriate men's size. This is a common mistake. Although sometimes the sizing can be adjusted, the best fit and least amount of complications come when a female employee selects footwear designed for the female foot.

JLab's safety shoe vendor is available onsite twice per month, with visits scheduled in advance on JLab's At-A-Glance calendar and also noted in the Briefs' Calendar of Events. All footwear orders should be placed through Webstock and approved prior to the vendor's onsite visit. If you need to procure new or replace aging protective footwear, click the link in the Calender of Events below for more information.


Last Chance to Register for the JAG Run-A-Round
Online registration for the 27th annual event is open through 5 p.m. on Tuesday, April 24. Participants must be registered to be eligible for event awards. Register or check out additional information on the JAG webpage. The JAG Run-A-Round is set for Wednesday, April 25, 3 - 6 p.m. JLab staff, users, students, full-time contractors and immediate family members are invited to participate. Staff and users who register for and participate in the run or volunteer can receive a free 2012 JLab T-shirt. The event will begin in front of CEBAF Center at 3 p.m. with the debut of the 2012 T-shirt. The run/walk will start promptly at 3:15 p.m. and cover a 2.2 kilometer (~1.36 mile) course. Food and beverages, music and the awards presentations will follow the race.

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 Harry Fanning, Jason Willoughby and Andrew Burrill, who were the first to correctly identify the April 11 location. Honorable mentions go to Samika Hawkins, Karen Bartek, DeAnn Maddox, Tonya Evans, Brita Hampton, Narciso Gomez, Ron Bartek, Pashupati Dhakal, Mike Martin and Michael Haddox-Schatz. 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

April 15-19: Beam Instrumentation Workshop
April 23: Safety Shoe vendor onsite
April 25: JAG Run-A-Round
April 30: FLUKA Training Course
May 2: Colloquium and Public Lecture
May 7: Safety Shoe vendor onsite
May 9-11: Science and Technology Review
May 14-17: QCD Evolution Workshop
May 19: JLab's 2012 Open House: Passport to Science
May 28: Memorial Day holiday, JLab closed