Jefferson Lab Weekly Briefs May 30, 2012
Jefferson Lab Weekly Briefs
May 30, 2012
In Hall C, the Q-weak experiment is finishing up electronics and data acquisition system checks and documentation. After warming the hydrogen target, the target was recooled twice with helium in the loop to measure the extent to which the target moves as it is cooled. The dis-assembly of Q-weak is starting.
Summer Lecture Series 2012 Calendar Posted
The week began with preparing the injector for the upcoming Polarized Electrons for Polarized Positrons (PEPPo) experiment. Equipment was locked out and jumpers installed by the Safety Systems Group to allow the experiment to continue while work is being performed for the 12 GeV Long Shutdown. On Thursday, the injector and North Linac were locked up to perform a hot checkout of the systems needed for PEPPo. A small punchlist was generated to be worked on Friday. On Friday morning, the injector and North Linac were locked up and work began with setting up the electron beam through the injector to the PEPPo platform. The weekend saw the optimization and characterization of the beam and detectors at multiple beam energy levels. A faulty video switcher in the injector caused a few hours of grief. It was eventually fixed by swapping it with an unused one from the accelerator. On Memorial Day, the electron and positron runs were used to characterize the spectrometer at different energies. The week ended with PEPPo performing coincidence optimization runs.
Center for Theoretical and Computational Physics
In a recent paper, Quantum Chromodynamics is studied at nonzero isospin chemical potential using a canonical approach by analyzing systems of fixed isospin number density. To construct these systems, a range of new algorithms for performing the factorially large numbers of Wick contractions required in multi-hadron systems are developed and used to study systems with the quantum numbers of up to 72 π+s. The systems studied correspond to isospin densities of up to 9 fm-3 and probe isospin chemical potentials, μI, in the range mπ <∼ μI <∼ 4.5 mπ , allowing for an investigation of multi-pion interactions and a verification of the conjectured transition of the system to a Bose-Einstein condensed phase at μI >∼ mπ.
Mechanical installation work is progressing well. To date, seven dipoles have been removed out of the east recombiner (R1) region and sent to the magnet measurement facility for dis-assembly and refurbishment. The refurbishment includes either reworking or replacing the coils, electrical improvements and other necessary upgrades to handle the higher energies that the 12 GeV machine will require. Additionally, the North and South Linac warm region girders (containing steering quads, corrector dipoles and beam position monitors) have been removed to support the 12 GeV cryomodule installation.
Facilities Management and Logistics
Cigarette Butt Causes Fire Outside of CEBAF Center
Environment, Safety, Health and Quality
Working on Energized Equipment
In such cases, only qualified persons may work on electric circuit parts or equipment that have not been de-energized. Such persons shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials and insulated tools. Click the link for a complete toolbox talk on this topic.
Last Chance to Get Your Hurricane Season Supplies - Tax Free!
Computing and Networking Infrastructure
Email Migrations into New System Continue
6 GeV End of an Era Party June 6 for Lab Staff, Students & Users
Last Chance to Pick Up Reserved T-Shirts
Tornado Warning Siren Test Set for Friday, June 1
Tracking Thomas at JLab
Congratulations this week go to Anusha Liyanage and Brita Hampton, who were the first to correctly identify the May 23 location. Honorable mentions go to Dick Owen, Samika Hawkins, Jodi Patient, Annie Tran, Ron Bartek, Stephen Wood, Mike Syptak, Rob Mahurin, Hyekoo Kang and Robert Martin. Check out the Tracking Thomas webpage for a better view of his last location and this week's new mystery photo.
JLab Calendar of Events
June 4: Safety Shoe vendor onsite