Jefferson Lab Weekly Briefs December 14, 2011
Jefferson Lab Weekly Briefs
December 14, 2011
12 GeV Upgrade
Closeout reports with lessons learned are being developed for the Six-Month Shutdown in preparation for the next shutdown scheduled to begin in May 2012. The “Long Shutdown” planning team for JLab has been established. A range of 12 GeV installation activities will be incorporated into the labwide integrated installation schedule for the shutdown. Facilities Management & Logistics support is integrated with 12 GeV projects through the FM&L work order system and is coordinated weekly.
Hall A is getting ready for a commissioning run to check the new beamline elements, detectors and data acquisition system. Most systems are ready, but there was a problem with the beamline vacuum system - too much torque developed on one section when vacuum was pulled. Some strong braces are being added to support this section. Meanwhile, work on the polarized target continues (the work is done by the target group) and is on track for installation, with the start of g2p/GEp in mid-February.
Q-weak continued production and background measurements on liquid hydrogen and aluminum at beam currents up to 180 microamps in Hall C. On Saturday, the Q-weak toroidal magnet power supply tripped, with a large number of failed fuses in one of its four transistor banks. While awaiting delivery of fuses, the physics program was switched to measurements of the asymmetry for the N to Delta transition, which requires a lower current at which the power supply will still reliably function. By end of Tuesday's day shift, the fuses were replaced and Qtor could run at full current; Q-weak returned to production running.
An air leak in the valve control system was discovered by Facilities Management & Logistics staffers. A tunnel access was made to repair it. Vacuum problems were traced to an open chassis door. A spin dance was performed to measure beam polarization. C100 testing was conducted to study the cryomodules' impact on beam quality and stability. These zones were turned off after testing. Circulator loads were replaced on zones in the North Linac. Throughout the week, Hall C's Q-weak experiment received 180 microamps of beam, while Hall B's HDice target received 40 nanoamps.
The alignment group continued supporting the installation in Hall A. Additionally, the final alignment of the Hall A beamline upstream of the FZ magnets was completed, and initial alignment of the chicane FZ magnets and components was started. Alignment also completed quality control inspections on a C100 vacuum vessel and spaceframe for the superconducting radiofrequency group. The magnet measurement group continued measurement and QC inspections of spreader/recombiner dipoles for the 12 GeV Upgrade.
Facilities Management & Logistics
Extensive JLab Power Outage Over Holiday Shutdown
JLab Calendar of Events
Dec. 16: JLab Library Open House
Environment, Safety, Health and Quality
Green Up Your Holidays
Computing and Networking Infrastructure
Computing Services Outage Will Precede Shutdown Power Outage
Beware Unexpected Online "Gifts"
Library to Hold Open House Dec. 16
Lands' End Logo Orders
Quark Cafe Holds Annual Holiday Bake Sale!
Colloquium: Potential "Sputnik Moments" for U.S. Energy Challenges
Personal Dosimeter Change Out Set for Dec. 19
Rad Workers: Read, Sign 2012 General Access RWP by Dec. 31
Annual Enrollment for TIAA-CREF 401(k) GSRA Ends Thursday, Dec. 15
Tracking Thomas at JLab
Congratulations this week go to Harry Fanning and Sebastien Procureur, who were the first to correctly identify the Dec. 7 location. Honorable mentions go to Michael Haddox-Schatz, Doug Higinbotham, Dena Polyhronakis, David Anthony, Sue Witherspoon, Andrea Celentano, Michelle Shinn and Sam Stevens. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.