Jefferson Lab Weekly Briefs April 13, 2011


Jefferson Lab Weekly Briefs
April 13, 2011

12 GeV Upgrade

With only five weeks until the start of the summer 2011 shutdown, the 12 GeV project installation activities have been integrated into the labwide schedule. Additional transportation and material handling equipment has been secured to support the effort. Existing trailers have been outfitted to support additional contract employees, and storage/staging locations are in place. The project team is finalizing work-planning documents in preparation for the down, as well as handover documents to Accelerator Operations and training for operators and technicians.


Hall A ran the short-range correlation experiment this week. The running was very efficient and the data is looking good. Accelerator availability has been excellent.

Q-weak has continued production data taking on the high-power hydrogen target with currents up to 165 microamps in Hall C. The data taking is interspersed with regular measurements of beam polarization and background asymmetry measurements on aluminum.


Last week, the CEBAF accelerator delivered beam to Halls A and C with 87.6 percent beam availability. Hall B has been offline for installation of HDice. During Tuesday’s beam studies, the Wien was flipped from right to left, and some optics data were collected for improvement of beam quality. On Thursday, the gun2 photocathode was heated and reactivated, resulting in 1.4 percent quantum efficiency of the cathode. Maintenance on the Arc2 dipole power supply was performed in parallel with the cathode activation. Performance over the weekend was robust with about 13 Coulombs/day delivered for physics research. Vigilant maintenance of the injector orbit over the past few weeks by Operations staff has contributed to the high availability. Identifying the source of the observed subtle injector orbit shifts is presently ongoing.

Free-Electron Laser

After getting the infrared FEL back up and lasing reliably from a seven-month ultraviolet hiatus, the FEL team spent the week setting up and starting two sets of IR optics measurements for Joint Technology Office/Office of Naval Research programs. The team also performed some double resonance terahertz experiments for the University of Southampton.

Computational and Theoretical Physics

This week, JLab is hosting the XIX International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2011), the premier annual meeting of the parton structure community. The meeting has approximately 350 experimental and theoretical nuclear and high-energy physicists from around the world, and is for practical reasons being held at the nearby Marriott City Center. Topics reviewed at the conference include structure functions, QCD, spin physics, electroweak physics and physics beyond the Standard Model, as well as the first results on parton distributions from the Large Hadron Collider.


The machine shop is presently drilling and taping the upstream and downstream ends of 37 four-meter XP-style magnets to accommodate the addition of end shims. The end shims are being laser cut by an outside source.

The shop is also continuing efforts in the manufacture of the deflecting mode Crab Cavity for Argonne National Lab. The prototype cavity has been trimmed for tuning, and the weld preps have been completed. The "Y"-shaped waveguide has been machined and is ready for welding. Since Feb. 28, the shop has processed 215 job requests.

The electric systems group (EES) reports that two more klystrons were received, as well. In addition, the second 12 GeV klystron cathode power supply has been delivered and placed in zone SL25 in the south linac along with klystron pedestals. With klystron pedestals and CPS's installed in zones SL24 and SL25, the 12 GeV radiofrequency systems are becoming a reality.

Environment, Safety, Health and Quality

Practice Window Safety to Prevent Falls
Each April, the National Safety Council takes a week to focus on the importance of practicing window safety in the home. National Window Safety Week reminds parents and caregivers how dangerous windows can be for unsupervised children. The National Safety Council offers these tips to help protect children from window falls:

  • Avoid placing any furniture near windows that young children can climb.
  • Do not lean on screens or rely on them to prevent a window fall.
  • Supervise children to prevent them from playing near windows, balconies or patio doors.
  • Install building code-compliant devices such as window guards (with quick-release mechanisms in case of fire).
  • Teach your children how to safely use a window to escape during an emergency.

Computing and Networking Infrastructure

CNI Maintenance Day Tuesday, April 19
The CNI group is planning a maintenance period for 5-7 p.m. on Tuesday, April 19. During this time, Windows and Linux patches will be pushed out and several central server machines will be rebooted. Plan on rebooting your Windows or Linux system on Wednesday to finalize patch installation. If you have questions or experience difficulties with your machine after rebooting, contact the IT Division Helpdesk, x7155. Additionally, the email server software will be upgraded. Thus, reading email from offsite may be unavailable for no more than 15 minutes. Onsite reading of email should not be affected.


Get in on Home Energy Savings With 'Next Step' Program
The DOE is funding a program designed to reduce home energy use and related costs. The Next Step program is available to home owners in specific jurisdictions in the Hampton Roads region and provides discounts for applicable energy-efficiency improvements. To learn more about this energy savings program and the potential benefits to homeowners in the JLab community, visit the Next Step display table in the CEBAF Center atrium on Earth Day, Friday, April 22, 11 a.m.-1 p.m. Additional information can also be found in this program announcement.

Education Seeks Projects, Mentors for Summer High School Interns
The Science Education staff is preparing for the lab's High School Summer Honors Program. Six local high school students will be at the lab from June 20-July 29. If you have a project or projects that would be good for one or more high-achieving high school students, send a short description of the project and what you'd like the student(s) to do to Brita Hampton, x7633. The students, currently in 10th and 11th grade, will be required to develop a poster about their project and present it during a poster session on the last day of their program. Ideas or proposals are needed by June 1.

Agilent Tour Bus Onsite
The Accelerator Division is hosting a visit by Agilent's Innovations Tour bus on Wednesday, April 27, 10 a.m.-2:30 p.m. in the parking lot on the east side (facing Res. Facility) of CEBAF Center. The bus will display a range of new products, including network analyzers, signal and spectrum analyzers, signal generators, oscilloscopes, protocol analyzers/exercisers, logic analyzers, digital multimeters and voltmeters, power meters and power sensors, DC power analyzers, semiconductor device analyzers and digitizers. All interested staff, students and subcontractors are invited to stop by the bus to look at Agilent's latest offerings and for product demos and technical discussions.

Tracking Thomas at JLab
Little Thomas is enjoying the spring weather this week. If you can identify his location, email Kandice Carter with your guess. The first correct response will receive special recognition on this page. Guesses are accepted through Fridays.

Congratulations to David Fazenbaker and Jason Willoughby, who were the first people to correctly identify the April 6 location. Honorable mentions go out to Simon Taylor, George Biallas, Mike Koch, Rebecca Yasky and Josh Foyles. 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 11-15: DIS2011
April 19: Science Series Lecture - The Science of Chocolate
April 20: JLab's Annual Region II Teacher Night
April 25: Safety Shoe vendor onsite