Jefferson Lab Weekly Briefs August 20, 2014

Jefferson Lab Weekly Briefs
August 20, 2014

12 GeV Upgrade

The last drift chamber for Hall B's CLAS12, one for Region 3, has had all wires strung, window added, feed-thru pins potted, and is being readied for testing. Three of the remaining 17 drift chamber sectors are having instrumentation completed, with the balance ready for installation. The production modules of the Silicon Vertex Tracker (SVT) barrel continue being assembled and tested at Fermilab, with over 30 now completed. The innermost modules of the SVT have been mounted onto the support frame/cooling plate in the clean room at Jefferson Lab and have been tested in place. The containment vessel for the High Threshold Cerenkov Counter (HTCC) has had the photomultiplier tube supports added and is being readied for mirror installation. All of the coated production mirror segments for the HTCC are being glued to form 12 half-sector mirrors. These will then be glued along their edges to form the full HTCC mirror. The aluminized Lexan strips that will be placed on the hyperbolic mirror segments of the Low Threshold Cerenkov Counter (LTCC) have arrived from the vendor and are being attached. A second full-size practice coil for the Torus magnet was wound, epoxy-potted and then sectioned to test the revised potting procedure. A good coating of all the coil elements was found. Pre-assembly of the Torus thermal shield is nearly complete at Jefferson Lab. The parts for the vacuum jackets have all arrived and are being welded as much as possible before the coil cold masses arrive from Fermilab. The vendor for the Solenoid magnet has wound 12 of the 26 layers of the practice coil. 


Jefferson Lab Published Journal Articles, August 11-15

  • I. Bedlinskiy et al. (CLAS Collaboration) "Exclusive pi0 electroproduction at W>2 GeV with CLAS."  Phys. Rev. C 90, 025205 (2014).
  • Simona Malace, David Gaskell, Douglas W. Higinbotham, Ian Cloet. "The Challenge of the EMC Effect: existing data and future directions." Int. J. Mod. Phys. E 23, 1430013 (2014).
  • Ling-Yun Dai and M. R. Pennington. "Comprehensive Amplitude Analysis of γγ to π+π-, π0π0 and KK below 1.5 GeV." Phys. Rev. D 90, 036004 (2014).

Remember to submit your papers for approval to the Jefferson Lab Publications database.

Center for Theoretical and Computational Physics

In a recent paper,  the covariant spectator theory (CST) was used to compute the π-π scattering amplitude, which was shown to satisfy the Adler self consistency condition, as required by chiral symmetry. Novel features of this theory and calculation are that it is carried out in real space-time (Minkowski rather than Euclidean space), so that it can be easily extended to real scattering and so that the dynamics can include a confining interaction with a scalar component and still have the correct chiral limit. The calculation was a serious test of the CST, because the Adler zero can be obtained only when contributions from the kernel are calculated to all orders.

Facilities Management and Logistics

CEBAF Center A & C Wing Restrooms to Close Temporarily for Refurbishment
The men's and women's restrooms in CEBAF Center, Wings A and C, are being refurbished to replace dilapidated partitions, lavatories and counters. The restrooms will be closed while refurbishment work is underway. The work will be done in two phases:

Phase I includes Wing A restrooms on the first and second floor.
Phase II includes Wing C restrooms on the first and second floor.

Phase I work is set to begin on Monday, Aug. 11, and should be completed within four weeks. Phase II work is planned to begin immediately thereafter and should take about the same time. Notification will be made in advance of the start date for Phase II.

Notices will be placed on the restroom doors while they are closed. The notices will include locations of other restrooms. The anticipated project completion date for all phases is late September. Facilities Management appreciates your patience during this brief inconvenience, as we work to provide safe, sanitary and upgraded restrooms.

Environment, Safety, Health and Quality

Migrating Critters
On the news last week, you may have seen the large canebreak rattlesnake that was captured by two individuals in an upscale neighborhood right at the front of a home. Unfortunately,  this isn't an odd occurrence. About this time of year, certain animals and insects enter a breeding season. They may also be moving to new "homes" due to the over-crowding at their current nest. With the spring/summer crop of offspring, they need to move, seeking an additional food source.

To avoid such encounters, you should be looking for animals before moving equipment that has been in the grass or along a fence or when trimming bushes, moving logs, raking leaves, etc. The venomous critters of Hampton Roads include copperhead/cottonmouth snakes, black widow and brown recluse spiders and stinging insects. Additionally, fire ants can be a big nuisance this time of year.

Computing and Networking Infrastructure

Get Jefferson Lab Site-Wide Alert Pager Messages on Your Personal Cell Phone
After the June 11 threatening situation exercise at Jefferson Lab, a number of people asked if it was possible to get Site-Wide Alert (SWA) pager messages over their personal cell phones. You can register your personal cell phone number in JList to  receive SWAs, weather advisories, laboratory closing notices and other alerts. Additionally, others at the lab will be able to text you from Jefferson Lab’s web staff-search application.

In order to register your cell phone number in JList, send an email to with email subject line "Add personal cell to SWA JList List." In the body of the email, provide your name, cell phone number including area code and the service carrier (Sprint, AT&T, Verizon, etc). Questions may be directed to

Cybersecurity: Protect Against USB Vulnerability
It has been widely reported in the news that two cybersecurity researchers have discovered a vulnerability in USB devices that they plan on presenting at the upcoming Black Hat conference. The vulnerability is not something that can be fixed with a patch, and hacked USB devices cannot be discovered with anti-virus software. The vulnerability is with the design of USB devices themselves. Although the bad news is that USB devices can be used to hack into systems, steal data and do other nefarious things, the good news is that using good judgment and existing best practices will mitigate the risks. As a reminder, do not connect USB devices to your computer that you don’t own or don’t have good reason to trust. Likewise, do not connect your USB devices to computers you don’t own or don’t have good reason to trust. Any time you need assistance with your Jefferson Lab computer system, contact the IT Division Helpdesk at or x7155.

For more tips on safely using USBs, see these recommendations from the U.S. Computer Emergency Readiness Team.


Jefferson Lab Employee Tour Set for Thursday, Aug. 28
Have you ever wanted to see the experimental halls and the accelerator tunnel, but have not had the opportunity to do so? Jefferson Lab employees, users, students and contractors will have that opportunity on Thursday, Aug. 28, 1-4 p.m. The tour will include stops at the Test Lab, the Machine Control Center, the accelerator tunnel, and experimental Halls B, C and D. The visit to each facility will be guided by subject-matter experts. Photos may be taken. Space is limited and your supervisor's approval and advance registration is required. For signup instructions and more information, see the all-staff memo posting.

Engineering Seminar: The European Spallation Source and its Safety Protection Systems   
The European Spallation Source, located in Lund, Sweden, is currently under construction. It includes a linear accelerator, which will send 2.86 ms-long pulses of 2 GeV protons at 14 Hz to a rotating tungsten target with an average power of 5 MW. This spallation source distributes thermal and cold neutrons to a variety of state-of-the-art neutron instruments, at which researchers from academiand industry will investigate scientific questions. ESS plans to deliver its first neutrons in 2019 and reach its full design specifications in 2025, with a suite of 22 research instruments. Decommissioning is foreseen to start in 2065. Annika Nordt will give an overview of the design of different protection and safety systems, such as the Machine Protection System (MPS), Personnel Safety System (PSS) and the Target Safety System (TSS). A statistical reliability model and the impact of early reliability modeling on the design of safety and mission critical systems will be discussed. The presentation will be held in the CEBAF Center auditorium at 1:30 p.m. on Thursday, Aug. 21.

Registration Underway for Sept. 12 United Way Day of Caring
The annual United Way Day of Caring will be Friday, Sept. 12. Jefferson Lab is in need of 20 volunteers to interact with patients at a veterans hospital and to assist them during their annual picnic. Volunteers will assist with setup during the early part of the day and then assist with food and activities throughout the picnic. No prior experience is required. Bring a friendly smile! Volunteers may sign up to participate before Friday, Aug. 29. If you wish to volunteer, please visit the all-staff memo webpage for signup details.

Jefferson Lab Calendar of Events

Aug. 21: Engineering Seminar
Aug. 26-28: Accelerator Readiness Review
Sept. 1: Labor Day, Jefferson Lab closed


JLab Weekly Briefs is an ongoing publication providing information on the status of safety, accelerator operations, experiments, free-electron laser, reviews, upcoming activities and special events. Deadline for submission is every Tuesday by 10 a.m. Submit new items to: Public Affairs or contact Kandice Carter at x7263.