Jefferson Lab Weekly Briefs

May 6, 2009

12 GeV Upgrade

The request for Best-and-Final Offers for the fabrication of the “Q1” superconducting quadrupole magnet for the new Super High Momentum Spectrometer in Hall C has been issued. This constitutes the first of the planned seven new superconducting magnets that will be procured. To initiate construction of the new CLAS12 wire chamber packages in Hall B, procurement of many of the component parts, such as wire and wire feedthroughs, has begun.


In Hall A, commissioning for the next two polarized helium-3 experiments, E05-015, A Measurement of the Quasi-Elastic Single Spin Asymmetry, and E08-005, Measuring the Transverse Asymmetry in the 3He(e,e'n) Reaction, has been successfully completed. Production running with 3-pass beam began April 29.

In Hall B, the damage on the polarized target that occurred during the insertion into CLAS last week has been fixed. The experiment has been ready to receive beam since April 29; after some startup problems, the beam was brought to the hall April 30, and first commissioning data have been taken. The data show excellent performance of the detectors. The target polarization is high (~80 percent).

Installation of the hypernuclear experiment continues in Hall C. The sieve slits for both the High Resolution Kaon Spectrometer and the High Resolution Electron Spectrometer are being installed, tested and aligned. The detector platform for the HKS has been placed. HKS and HES detectors are being tested in the Experimental Equipment Lab prior to installation in Hall C. The Hall C summer physics workshop is planned for August 6-7.


The accelerator was performing relatively well with a low trip rate. On April 29, Hall A was changed from 1-pass to 3-pass, and Hall B started to take 5-pass beam. The Arc4 box supply tripped off a few times, and investigation of the problem continued. The beam in the injector was having a slow drift, most likely caused by gun anode grounding; the problem was fixed. The insulating vacuum pump for zone 1L06 tripped off twice; the cause was identified, and the problem was corrected. Also, there was some routine maintenance on the radiofrequency system.

Free-Electron Laser (FEL)

The low-conductivity water line is being installed. Taking advantage of the gap in operations, FEL staffers are continuing installation work on the ultraviolet branch and replacing some diagnostics on the main machine. They have also been working to understand the location of the field emission in the gun, to increase the power and stability of the drive laser, and to improve the optical transport system.

Theory Center

A new Theory Center paper <arXiv:0905.0466 [hep-lat]> presents the results of an exploratory lattice QCD calculation of three-baryon systems through a high-statistics study of one ensemble of anisotropic clover gauge-field configurations at a pion mass of mπ ~ 390 MeV.  The energy of a three baryon system is extracted for the first time, focusing for the most part on a system with the quantum numbers of two Ξ's and a neutron for computational expediency, but also providing first results for the channel containing the triton. This present work establishes a path to multi-baryon systems and shows that lattice QCD calculations of the properties and interactions of systems containing four and five baryons are now within sight.

JLab's Safety Numbers

121 Days since Last Recordable Accident (JLab record: 331)
238 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

May 20: JLab Annual Run-A-Round
May 25: Memorial Day holiday, lab closed
May 27: Safety Glasses Vendor onsite
May 28: Safety Shoe Vender onsite
June 1-19: HUGS 2009
June 2-4: 53nd Annual Materials Management Workshop
June 8-10: Users Group Workshop and Annual Meeting




Environment, Safety, Health & Quality

The Corrective Action Tracking System database now allows users to enter Facilities Work Orders as they enter their CATS items. Previously, all issues associated with a single CATS item had to be entered, saved and then re-typed into the FML system individually. In the improved configuration, a checkbox at the bottom of each individual issue entry allows users to create a Facilities Work Request. Additionally, all common information between the two systems is pre-populated within the FML system. This new functionality was implemented as a result of site feedback, specifically the CATS users group, and is intended to save time for CATS users.

Additionally, newly revised ESH&Q Manual chapters are now available on the JLab website. They include 6650 Engineered Nanoparticle Policy, 6650 Appendix T1 Miminum Mitigation Requirements for Engineered Nanoparticles, and 6650 Appendix T2 Emergency Procedure for Engineered Nanoparticles.

Computing and Networking Infrastructure

Computer User Audit Underway
The JLab semi-annual user audit started on Monday. If you are a supervisor or sponsor, you should have received an e-mail asking you to go to Insight and complete your audit. This audit is critical to maintaining an appropriate level of security here at the lab. All audits are required to be completed by the end of the day on May 26.


JLab Community Mourns the Loss of Cornelius Bennhold
The JLab community was saddened to learn of the untimely passing of Cornelius Bennhold, a professor at The George Washington University who was an active and effective participant in the research program at JLab since its beginnings. A copy of the tribute to Bennhold written by his colleagues has been posted on the JLab website. Colleagues and friends of Bennhold are encouraged to share anecdotes and expressions of condolence or of celebration for the life that he lived via the websites identified in the tribute.

TIAA-CREF Individual Counseling Sessions Available
The June date for individual counseling sessions with Robert Jean, of TIAA-CREF, is Wednesday, June 17. The Individual Counseling Session will help you plan your retirement by providing objective advice and asset allocation based on your individual needs; showing you how you can get a personalized actionable plan and reviewing your retirement income options. To sign up for an appointment, visit the TIAA-CREF website, click on Meetings & Counseling and follow the menu. The sessions will be held in VARC 42.

2009 Jefferson Activities Group Run-A-Round Set for May 20
Dust off those running shoes! The 24th annual Jefferson Activities Group Run-A-Round will be held Wednesday, May 20, from 3-6 p.m. JLab staff, users, full-time contractors and immediate family members are invited to participate. Staff and users that participate can receive a free 2009 JLab T-shirt by turning in their Run-A-Round race bibs at the T-shirt distribution tent. You can find more information and register for the Run-A-Round online. Volunteer sign up is also available via the JAG webpage.

Virginia’s Hurricane Preparedness Sales Tax Holiday
All Virginians should take steps to prepare their families for any emergency by getting an emergency supply kit, making an emergency plan and staying informed about the hazards that could affect their area. Detailed instructions for getting ready for emergencies are online. The General Assembly established an annual sales tax holiday to ease the cost of creating an emergency supply kit. From May 25-31, the purchase of certain items is exempt from the Commonwealth’s sales and use taxes. Customers may use manufacturer’s coupons to lower the price of an item so that it will qualify for the $60 or $1,000 price cap. Items include bottled water, flashlights, battery-powered radios, batteries and first aid kits. The entire list of tax-free items is available online.

U.S. Postal Rates increase Monday, May 11
On May 11, the price for a one-ounce First-Class Mail stamp will increase from 42¢ to 44¢. Prices for other mailing services — Standard Mail, Periodicals, Package Services (including Parcel Post), and Extra Services — will also change. Click here for more information.

APS Toy Box Physics Contest
Like tossing yo-yos? Ever wanted to unravel the mystery of the drinking bird? Then the Toy Box Physics video contest is for you. Take any toy you want and use it to somehow express a physics concept. Bounce, spin, jump and splash your way into physics history. The winner will receive a trophy lovingly made by American Physical Society staff from some of our favorite physics toys as well as $1,000 cash. All entries must be received by May 26 at midnight.