Jefferson Lab Weekly Briefs October 21, 2009
Jefferson Lab Weekly Briefs
October 21, 2009
12 GeV Upgrade
The two FY10 procurements for 12 GeV civil construction are on schedule for award in the second fiscal quarter. The solicitation for the North and South Access Building Additions is being prepared by the JLab Procurement Group, and the site visit will be held in the beginning of November. This contract includes 1800-square-foot additions to each of the access buildings and new electrical unit substations for the accelerator power supplies to be installed in these buildings. The other FY10 civil construction procurement is the Central Helium Liquefier (CHL) Utility Upgrades, cooling towers and transformers, to support the CHL #2 compressors.
For the past week, experiment E05-109, HAPPEx-III, a measurement of the nucleon strange form factors at high Q2, has taken production data under excellent beam conditions, both with respect to helicity-correlated properties and background conditions in the Compton polarimeter in Hall A.
Last Chance to Submit Your APS April Meeting Abstract
The accelerator has been running well with low trip rates. On Thursday, the injector was optimized to deliver better beam. Several minor issues were addressed this week, including: the insulating vacuum pump for zone 1L03 failed and was replaced; the Arc1 Box Supply failed, and the power supply was replaced; the radiofrequency separators tripped off twice; and a couple of trim rack power supplies were replaced.
The FEL had a good week of running tests for beam, a Colorado State optics study and one user test. The gun continues to operate exceptionally, maintaining its quantum efficiency at operational levels over the entire week without additional cesiation. Installation and checkout of the ultraviolet beamline also made great progress; the FEL team intends to thread beam through the line for the first time next week.
Members of the JLab lattice QCD group have calculated the spectrum of mesons composed of quarks with masses around that of the strange quark. The results <arXiv:0909.0200> include the first determination of the mass of a spin-4 meson, the identification of states with exotic quantum numbers and a vector-hybrid candidate. The next steps are to lower the quark masses and to develop methods for dealing with two-particle states, before eventually calculating meson-photon couplings. This program of calculations will inform expected production rates for GlueX at 12 GeV, as well as providing the ab initio predictions for the meson masses demanded by experiment.
JLab's Safety Numbers
98 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
Oct. 28: William F. Brinkman, Director of DOE's Office of Science, visits JLab
Environment, Safety, Health & Quality
The following information was developed by various organizations (in parentheses) to help make people aware of the hazards of driving while distracted:
For more information, visit the Drive Smart Virginia website.
Computing and Networking Infrastructure
Tips for Curtailing Spam
Performance Appraisals Update
Hand Sanitizer Still Available
Access Your United Way Pledge Form Electronically
If you wish to use the traditional form, it is available for pickup at the following locations: CEBAF Center Lobby, VARC Lobby, ARC Lobby, Test Lab 2nd Floor Lobby and MCC Lobby. Detach and keep the pink carbon for your personal record and send the rest of the completed form, along with any check payments attached, to Joshua Cameron.