Jefferson Lab Weekly Briefs March 23, 2016
Jefferson Lab Weekly Briefs
March 23, 2016
Jefferson Lab Published Journal Articles, March 7-18
Publications Refresher Course Offered March 28
JSA Offers Sabbatical and Research Leave Support at Jefferson Lab
Center for Theoretical and Computational Physics
A new computation of the strange-antistrange asymmetry in the proton has been performed within chiral effective theory, which includes off-shell and contact interactions, in addition to the usual kaon loop contributions with on-shell intermediate states, which were only accounted for in previous calculations. Using a regularization procedure that preserves chiral symmetry and Lorentz invariance, the analysis finds that existing data limit the integrated value of the asymmetry to the range -0.07 × 10-3 ≤ (x<s-s>)≤ 1.12 × 10-3. In contrast to some suggestions in the literature, the magnitude of this correction is too small to account for the so-called NuTeV anomaly, which found an anomalously large value for the weak mixing angle.
In the last few weeks, the Alignment group has been active in Halls A, B, C and D. Additionally, surveys have taken place in the Upgrade Injector Test Facility beamline located in the Test Lab. In Hall A, the group has carried out surveys of the spectrometers and the Deeply Virtual Compton Scattering calorimeter, as well as surveys around the Compton line. In Hall B, the group has measured the new 12 Gev Torus, assisting Hall B personnel in obtaining the best orientation of the Torus cold masses to the beamline. Also in Hall B, control work was undertaken to make sure the accelerator and hall's coordinates were current. Additionally in Hall B, the crews assisted the Hall B crews to align the supports for the Low Threshold Cherenkov Counter detectors and Panel 2 forward time of flights. Hall C work has focused on the Hall C dump and on the mapper for the Super High Momentum Spectrometer bender magnet. Beam position monitors were measured in the Hall D access line (5C). New control points have been installed and measured in the UITF cave in preparation for beamline layout and alignment.
The magnet measurement group has been working hard to set up a prototype measurement system for measuring Hall B's Torus magnet.
Jefferson Lab Calendar of Events
March 29-31: JLEIC Collaboration meeting
Volunteer Now for Jefferson Lab Open House on April 30!
Professional Development Lunch and Learn Offered April 5
Notice to All Radiation Workers
Enrollment Deadline for Excel and PowerPoint Training Is March 25
Jefferson Lab Community Invited to Retirement Reception for Dave Kausch on April 4
Last Chance to Vote for the 2016 JLab T-Shirt Design
Education Seeks Projects for Summer Honors Interns; Send Ideas/Proposals in by May 2
Research Assistantship Program Now Taking Nominations
Property Validation Deadline Approaches
|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.|