Jefferson Lab Weekly Briefs May 1, 2013
Jefferson Lab Weekly Briefs
May 1, 2013
12 GeV Upgrade
Detector construction for the Hall C Super High Momentum Spectrometer continues, with drift chamber stringing progressing at Hampton University and the vessel readied for the heavy gas Cerenkov counter. For the HB dipole magnet, machining of the helium vessel is underway, and the designs of the liquid nitrogen (LN2) shield and vacuum vessel are in final check. The stacking and welding of the steel laminations that form the yoke for the Q1 quadrupole magnet has passed the halfway point. Tests of the epoxy impregnation method to be used for the coils of the dipole, Q2 and Q3 magnets have been completed; production of the automated tooling to consolidate the conductor into its final form is underway; and a first test winding of the dipole magnet using the final conductor was done. Installation of the rails for the SHMS support carriage is complete, and an award of the main contract to assemble the support carriage is being prepared. Final machining is complete for the hundred tons of magnet steel yokes.
Work will begin soon in both the North and South Linac Service buildings to add additional cooling capability. When this work commences, new construction work areas will be established. The work areas will be under the control of the contractor and will require additional PPE for entry. As with any construction area, access will be restricted to those having a specific need to be there. The work permit will be posted and will list the SOTR responsible for coordinating activities in the designated construction area.
PAC Proposal Deadline Nears
Program Posted for Users Group Annual Meeting
The FEL team held a kickoff meeting for the collaboration in timing and bunch length measurements with Colorado State University this week.
Center for Theoretical and Computational Physics
A new, comprehensive analysis of γ-Z interference corrections to the weak charge of the proton, measured in the Q-weak parity-violating electron scattering experiment, has just been completed by the Adelaide-JLab-Manitoba (AJM) collaboration. Constraints from parton distributions in the deep-inelastic region, together with new Hall A data on parity-violating electron scattering in the resonance region, result in significantly smaller uncertainties on the corrections compared to previous estimates. The new constraints also allow precise predictions to be made for parity-violating deep-inelastic asymmetries on the deuteron planned in future 12 GeV measurements at JLab.
The Electrical group has been busy with many installation activities around the accelerator. The first of the five spreader/recombiner regions has had all magnets reconnected electrically, and the area is ready for quality assurance checks to commence. All installed magnetic elements in the east and west arcs have been connected. The Radiofrequency group has completed the commissioning of North Linac RF Zone NL22, and cryomodule commissioning is in progress. NL24 is ready to start cryomodule commissioning and RF systems tests are being done in zone NL23. Restoration of the 42 6 GeV RF systems has begun with much needed maintenance(preventive maintenance - PM) and checkout work in progress. As PM is finished, the RF system and cryomodule operation are re-established and the performance measured.
The Safety group is supporting RF system re-certifications, so these systems can be restored. The Instrumentation group is working on installation and hookup of the beam diagnostic and vacuum equipment around the accelerator. Great progress has been made, but much remains to be done.
JLab Calendar of Events
May 3: TEDxCERN Simulcast at JLab
Environment, Safety, Health and Quality
On-Site Emergency Phone Number Reminder
TIAA-CREF Onsite Individual Counseling Sessions
Ready, Set, Register for the JAG Run-A-Round
Education Seeks Two More Projects for Summer Honors Interns
Monthly Tornado Siren Test Set for Friday
RIM Trivia Question of the Week
Reminder: U.S. Customs and Border Protection (CBP) Announces Automation of Form I-94 Arrival/Departure Record
Tracking Thomas at JLab
|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.|