Jefferson Lab Weekly Briefs
March 3, 2010

12 GeV Upgrade

The winter 2010 tunnel work for 12 GeV installation has been completed. Planning efforts for the summer 2010 scheduled accelerator down are in progress. Activities include installation of the remaining west arc low-conductivity water (LCW) supply and return lines, Arc 10 stand installation, the remaining four cryomodule base plates, radiofrequency (RF) waveguide hangers and cable installations. Planning efforts for 12 GeV installation activities during the scheduled six-month accelerator shutdown (May-November 2011) are also in progress. 

Physics

In Hall C, water and power connections to the Q-weak torus magnet were completed and the magnet has so far been tested to 5000 Amps, which is more than 50 percent of the operating current. The magnet mapping has been completed. The mapping data will be used to check the coil positions and verify the symmetry of the magnet. Installation and alignment of the beamline continues.

Accelerator

The accelerator has been locked up and is in beam permit. Eighty percent of the RF and all of the box supplies have been turned on. Some of the scheduled maintenance work is complete, and the rest is in the final stage.

Free-Electron Laser

The FEL team completed a lot of work in preparing the FEL beamline for re-establishment of lasing. However, the team is still awaiting the U-tube connections and cooldown of the new cryomodule and the commissioning of that system. The FEL remains inoperable until it receives support for this work.

Theory Center

Although the Δ(1232) resonance plays a fundamental role in nuclear reactions, its electromagnetic properties are largely unknown, with the exception of scarce indirect information extracted from data on the electromagnetic N to Δ transition, together with very recent lattice QCD calculations. Recently, a relativistic quark model, adjusted to fit both experimental data and lattice QCD simulations, was used to predict the electromagnetic structure of the Δ <arXiv:1002.4170 [hep-ph]>. In addition to the charge and magnetic dipole distributions, the model makes predictions for the higher order electric quadrupole and magnetic octupole form factors, which may be tested by lattice QCD calculations in the near future.

Facilities Management & Logistics

Construction of new cooling towers is underway just inside the accelerator site gate to replace the existing cooling towers, which are 20-45 years old and are located south of the Test Lab. The new site has room for additional towers to support future loads. The pedestrian walkway between the accelerator site gate and the North Access Building has been rerouted to accommodate the construction and will remain in place until this summer. The cooling towers and piping to the Test Lab chiller plant will be installed during March and April. Access to the exterior southwest area of the Test Lab may be limited. For more information, contact Celia Whitlatch, x6299.

JLab's Safety Numbers

40 Days since Last Recordable Accident (JLab record: 331)
40 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

March 6: Virginia Regional Middle School Science Bowl
March 10: Colloquium: Physics and Forensics
March 14: Daylight Saving Time begins
March 25: Safety Shoe Vendor onsite
April 14-15: AVS Mid-Atlantic chapter meeting and short course
April 21: JLab Teacher Night
May 1: Jefferson Lab Open House

 

 

 

Environment, Safety, Health & Quality

Most JLab employees use hard hats infrequently. It's good to review a few simple tips about hard hats before using them. The shell should be inspected routinely for dents, cracks, nicks, gouges and any damage that might reduce protection. Any hard hat that shows signs of wear or damage should be removed from service immediately. The shell material may be degrading if the shell becomes stiff, brittle or faded or appears dull or chalky. With further degradation, the shell’s surface may flake or delaminate. A hard hat should be replaced at the first sign of any of these conditions.

Here is a two-part, simple hard hat inspection technique:
• Compress the shell from both sides about one inch with your hands and release the pressure without dropping the shell. The shell should return to its original shape quickly, exhibiting elasticity. Compare the elasticity with that of a newer shell if you are not sure about the result. If it does not have as much elasticity as a new shell, or if it cracks, it should be replaced immediately.

• Inspect the suspension system closely for cracks, cut or frayed shell straps, torn headband or size adjustment slots, loss of pliability or other signs of wear. Remove and replace any suspension that is damaged.

New equipment may be obtained from the stockroom. If you have specific questions about your hard hat or the need for hard hats in general, contact your division ESH&Q Liaison or your Safety Warden.

Computing and Networking Infrastructure

CNI Maintenance Day Set for March 9, 5-10 p.m.
The CNI group is planning a maintenance period from 5-10 p.m. on Tuesday, March 9. During this period, several web servers will be rebooted. In addition, there will be some reboots of Subversion servers. These changes should all be complete by 10 p.m. on March 9. If you have questions or concerns, you may contact the Helpdesk at x7155.

Announcements

Recharge Each Wednesday Afternoon in the Quark Cafe
The Quark Cafe will be open this afternoon from 3-4 p.m. for Recharge Wednesday. Today's featured snack is the banana split.

Education Seeks Mentors for Summer Programs Participants
The Science Education staff needs your help. Seven regional high school students will be at the lab June 21-July 30 for the High School Summer Honors Program. A mentor with an appropriate project is needed for each student. In addition, 20 teachers will be here July 5-30 for the DOE Academies Creating Teacher Scientists program. Mentors with hands-on projects where groups of three teachers could work about 40 hours each over the length of the program (about 10 hours per week per teacher) are needed. Participants will develop a poster about their project and present it on the last day of their program.

If you have a project or projects that would be appropriate for a high-achieving high school student or for a small group of dedicated science teachers, e-mail a short project description and the proposed work requirements to Christine Wheeler.

Middle School Science Bowl Practice Session
A practice session for volunteers for the Middle School Science Bowl is set for Friday, March 5 at 9:30 a.m. in CEBAF Center room F113.

Physics and Forensics Colloquium and Public Lecture
A colloquium on the connections between physics and forensics will take place at 3:30 p.m. in the CEBAF Center auditorium on Wednesday, March 10. John A. Reffner, John Jay College of Criminal Justice, CUNY, will show how physics underlies many of the tools of the trade that are used in forensic science. In particular, spectroscopy and spectroscopic imaging are critical in many analytical situations. Ultra-bright light sources, such as are produced by accelerators, allow higher spatial resolution work for specialized applications. Reffner will not focus on accelerator-produced light, but rather give a more general introduction to the forensic science field, with examples drawn from his personal experience solving cases.

Annual T-Shirt Design Contest Underway
The deadline for submissions for the 25th Annual JLab T-shirt Design Contest is March 26. Submissions should be in color, on 8.5x11 paper and include a front (pocket) and back design. Submission rules and past winning designs are posted on the JAG website.