Jefferson Lab Weekly Briefs July 22, 2015
Jefferson Lab Weekly Briefs
July 22, 2015
12 GeV Upgrade
Both of the large, refurbished quadrupole magnets have been put in place for the Moller Polarimeter in the beam tunnel upstream of Hall C, while downstream of the hall, removal of aged equipment from the beam-dump tunnel is taking place. Delivery has been made of about half of the new beam pipes and stands that will run from the pivot to the dump tunnel entrance. Inside Hall C itself, installation of the Personnel Safety System on the new spectrometer has been completed and shielding blocks are being cleaned and brought in so they can be stacked to form a wall just behind the Super High Momentum Spectrometer (SHMS).
The Q1 magnet acceptance tests and final alignment have been completed, and that fabrication contract is now closed-out. Low-current measurements involving the Horizontal Bend (HB) magnet continue. Careful, methodical testing and modeling of the components of this superconducting magnet are required to demonstrate that a quench, or any other sudden interruption in the current supplied to the magnet, will not damage it. The coil of the main SHMS dipole magnet, collared last month, is now integrated with its steel helium vessel. The Q2 magnet coil has undergone its final potting and been sent for machining on a giant lathe; splicing of the sub-coils of the Q3 magnet coil assembly has been completed.
Installation of mirrors, photomultiplier tubes and windows of the Noble-Gas Cerenkov has started in the Equipment Service Building, as has cosmic-ray testing of one of the drift chambers. These detectors are scheduled to go into the hall in Summer 2016, after the dipole magnet is installed.
Jefferson Lab Published Journal Articles July 6-10
Remember to submit your papers for approval to the Jefferson Lab Publications database.
Center for Theoretical and Computational Physics
The first coupled-channel π-π and K-K analysis has been performed in lattice QCD, from which the ρ-meson resonance has been extracted at a pion mass of 236 MeV. The coupled-channel scattering amplitudes have been derived from a detailed spectrum of finite-volume energy levels, allowing a pole to be identified in the complex energy plane that corresponds to the ρ resonance. The mass and width are found to be closer to the experimental values than in previous analyses with larger pion masses, and the K-K channel is essentially decoupled for this energy region, which is in good agreement with experimental observations.
Jefferson Lab Calendar of Events
July 27: Safety Shoe vendor onsite
Environment, Safety, Health & Quality
Pay Attention as a Pedestrian
Recently, it's been noted that there have been a number of pedestrians on the Jefferson Lab site that have been walking while distracted. As a pedestrian, you can greatly reduce your risk of injury by always being aware of your surroundings and by not letting a cell phone, iPod or other device distract you as you walk through parking lots, cross streets or use intersections.
Lab Community Invited to Summer Interns Poster Session on July 31
Deadline Nears for JSA Initiatives Fund Proposals
*Locations Changed* TIAA-CREF Individual Counseling Available by Appointment
Jefferson Lab Employee Tour Set for Thursday, Aug. 27
Looking for Summer Fun? Discount Entertainment Tickets Available
|JLab Weekly Briefs is an ongoing publication providing information on the status of safety, accelerator operations, experiments, free-electron laser, reviews, upcoming activities and special events. Deadline for submission is every Tuesday by 10 a.m. Submit new items to: Public Affairs or contact Kandice Carter at x7263.|