Jefferson Lab Weekly Briefs February 2, 2011
Jefferson Lab Weekly Briefs
February 2, 2011
12 GeV Upgrade
Twenty-four of the total 48 barrel calorimeter (BCAL) modules for Hall D have now arrived from the University of Regina. The first 500 production units of the new Cockcroft-Walton type high-voltage synthesizer-and-divider bases for the forward lead-glass calorimeter in Hall D are beginning to arrive at Indiana University. Extensive testing of the first two production boards of the custom 16-channel 250 Megahertz Flash Analog-to-Digital Converters (FADCs) has been performed with excellent results. Several rings of straws have been inserted into the endplate support structure for the central drift chamber at Carnegie Mellon University. The first of the four superconducting coils for the Hall D solenoid was successfully tested to 1200 Amps in the Test Lab last month. The installation and testing of the second coil is underway.
Last week, the accelerator was running with some downtime due to troubleshooting high-current beam delivery instability (100 microamps or higher). The gun high voltage, the warm and cold radiofrequency system and the magnets in the injector were checked, and all appeared to be working normally. On Monday, the beam optics in the injector chicane region was optimized based on the design, and Operations staff members were able to deliver high current (150 uA) afterward. The Hall B nanoamp beam position monitor system is working well since the lock-in amplifiers were shielded from radiation.
Last week was the second and final week of hosting the U.S. Particle Accelerator School, with hands-on experience for 12 individuals and with the FEL performing extremely well. The team received feedback from the school organizer that using the FEL for this course had been a huge success.
Theoretical and Computational Physics
A new review article <arXiv:1101.2482> on generalized parton distributions and their experimental studies at JLab has been compiled by Theory Center staff and experimentalists from France. In particular, experiments on Deeply Virtual Compton Scattering performed in Halls A and B are discussed, and plans for DVCS and deeply virtual meson production at 12 GeV are outlined.
The next scheduled presentation in the Engineering Division Professional Development Program has been moved to the CEBAF Center auditorium due to overwhelming demand for the course. The Cycle Design/Carnot Analysis lecture will be presented by Rao Ganni on Feb. 8 at 1:30 p.m. Advance registration is required.
JLab Calendar of Events
Feb. 5: Va. Regional High School Science Bowl
Environment, Safety, Health and Quality
Proper Work Planning Alteration
Computing and Networking Infrastructure
JLab_guest Wireless Change On the Way
New Mathematica and Maple Versions Available in CUE
Big Game Tailgate Lunch in Quark Cafe on Friday, Feb. 4
Plan Your JLab Tour Now
Onsite TIAA-CREF Counseling Offered
Colloquium: Nanotubes - 20 Years and Into the Future