Jefferson Lab Weekly Briefs
February 6, 2013
12 GeV Upgrade
Assembly of the ninth C100 cryomodule is complete, assembly of the 10th is progressing, and acceptance testing of the sixth C100 continues in the Test Lab. Work on the new radiofrequency zones continues. Connections of the power supplies to the quadrupole and corrector dipole magnets is underway in the east arc beamlines. Preparation of the 4.5 Kelvin coldbox for the Central Helium Liquefier-2 continues for February commissioning, and assembly is underway of the transfer line that will connect CHL2 to the linacs. Re-installation of the east spreader and east recombiner is complete except for the BCOM dipoles (magnets at the linac-end of the segment with multiple beams passing through them); installation of girders and dipoles for the west recombiner is underway. The first reworked BCOM dipole has been tested and has met specifications. The first 3-meter-long ZA septum magnet is installed; the fourth ZA has been received. The Personnel Safety System for the North Linac achieved certification. A final functional review of the new beam position monitor electronics is scheduled for next week.
The demolition of the Short Orbit Spectrometer shield house in Hall C is nearing completion. The shield house is being removed by using diamond wire cutting to separate the shielding into pieces that the hall crane can lift. The rails on which the Super High Momentum Spectrometer will rotate have been placed on rail beds that have been bolted to the floor.
Installation of the ring resonator hardware is going well and should be ready by the time the beam is able to be turned on. That is slated for around April 1 after repairs to the Central Helium Liquefier are completed and the machine is cooled to 2 Kelvin. FEL staffers are making good progress on the design of the gun upgrade and producing procurement packages for the hardware. The team sent the procurement package for a wiggler for the Navy INP FEL program to JLab Procurement for release.
Center for Theoretical and Computational Physics
The scattering lengths and effective ranges that describe low-energy nucleon-nucleon scattering are calculated in a new paper in the limit of SU(3)-flavor symmetry at the physical strange-quark mass with lattice QCD. This is done by determining the energy levels of the two-nucleon systems at finite volume from which the low-energy elastic phase shifts in each channel are computed. These phase shifts are parametrized well using the effective range expansion from which the scattering length and effective range are obtained.
Dog-Friendly Landscaping Tips and Therapy Dog Class
JLab Blood Drive a Success!
New Dates Offered for Onsite TIAA-CREF Counseling
Tracking Thomas at JLab
Samika Hawkins, Buddhini Waidyawansa, Becky Mosbrucker and Andy Kowalski correctly guessed the location for Jan. 30. Honorable mentions go to Mike Staron, Lori Zukerman, Luci Collins, Michael Haddox-Schatz, DeAnn Maddox, Daniel Moore, Dana Cochran, Saptarshi Mandal, Tim Whitlatch, Brita Hampton, Kim Kindrew, Sue Witherspoon, Todd Satogata, Chris Stanislav, Ron Bartek, Kelly Tremblay, Michael McCaughan, Stephanie Vermeire, Gwyn Williams, Katherine Myers, Connie Adams, Alexei Prokudin, Russell Mammei, Charlene Polk, Rob Mahurin, Andrea Celentano, Doug Higinbotham, Casey Heck, Deborah Dowd, Sandra D'Souza, Sam Holben and Chris Wicker. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.
Environment, Safety, Health and Quality
LNT at JLab
So why LNT at JLab? Recent walk-throughs have discovered floors covered with discarded materials, parts and supplies. Some areas were such that one could almost not walk through without stepping on something that could slip from underfoot, resulting in a fall. These observations revealed that some JLab workers were just not cleaning up after themselves in open work areas.
JLab runs extremely "clean machines" (the Accelerator and the FEL), so why not operate all our jobs and work areas that way? Pick up any mess that you create - this makes the work environment safer both for you and for those coming later.
Computing and Networking Infrastructure
Computer User Account Audit
JLab Wireless Certificate Changes
Java Update Set for Tonight
Java 1.6 End-of-Life Preparations
JLab Calendar of Events