Jefferson Lab Weekly Briefs

October 14, 2009

12 GeV Upgrade

Construction continues on the first barrel calorimeter module for Hall D, with lead- and fiber-layered assembly now complete at the University of Regina in Saskatchewan, Canada, and machining of the assembled module started. One quarter of the total fibers needed for this detector have now been received, with all samples passing quality assurance checks. The endplate for the central drift chamber detector for Hall D has been released for fabrication, and construction of the prototype layers for the forward drift chamber is proceeding at JLab. 

A meeting was held at JLab to plan construction of a complete prototype chain, from sensors to data acquisition, of the silicon vertex tracker for Hall B. The bid process has begun for the five large power supplies needed for the Hall C Super High Momentum Spectrometer superconducting magnets.


In Hall C, the hypernuclear experiment continues production data taking, with recent data taking using lithium and boron targets. A polyethylene (CH2) target has been installed in order to perform optics and missing mass calibration with Lambda production on hydrogen. With the approach of the Q-weak installation period, the Q-weak toroidal magnet (QTOR) spectrometer has been disassembled at MIT/Bates and shipped to JLab. The eight copper coils, weighing 12,000 pounds each, have arrived and are being fiducialized before being moved to the hall.

REVTeX 4.1 Released
The first update to REVTeX since 2001 is now available. REVTeX 4.1 is a set of macro packages designed to be used with LaTeX2e. REVTeX 4.1 includes bug fixes, improved functionality and support for a wider range of journals, including those of the American Institute of Physics and the American Physical Society. For more information and a link to the updates, visit the AIP website.

APS April Meeting Abstract Submission Deadline is Oct. 23
The 2010 APS April Meeting will take place at the Marriott Wardman Park Hotel in Washington, DC. Because the April Meeting will be held in conjunction with the annual winter meeting of the American Association of Physics Teachers (AAPT), it has been moved to February. The deadline for receipt of abstracts is Friday, Oct. 23, at 5 p.m. EDT (2 p.m. PDT).


Operations personnel delivered beam to the halls with some down times. On Thursday, the Central Helium Liquefier tripped due to a failed uninterruptable power supply. The injector was optimized to deliver high current to Hall C. Time was also spent to optimize the injector to stabilize the beam on a couple of occasions. It appeared that beam in the injector had been drifting for a few days, but the root cause of the drifting has not been identified. Beam has been stable since Monday evening after some injector tuning.

Free-Electron Laser

The FEL ran extremely well again this week. New operating conditions were investigated, and good lasing took place at 3.86 and 3.4 microns. In addition, the FEL team ran beam into user lab 6 and confirmed that all nine optics were performing well. The team is preparing for the first electron beam through the ultraviolet transport line. A short in one of the UV magnets was located and repaired, and the team is preparing to measure the fields in all the magnets and to check out the diagnostics. A group of users from Aerospace Corp. upgraded their setup in user lab 4 and successfully ran some machining tests using a table-top laser. This is an important step in preparation for using the FEL.

Theory Center

A new computational technique is described <arXiv:0910.0992 [hep-lat]>, in which the cost of solving the linear systems in QCD calculations using anisotropic lattices can be accelerated by a factor depending on the lattice anisotropy. In testing, the condition numbers of the fermion matrix - which is a measure of how difficult it is to solve the linear system - were improved by a factor between two and three, compared to the traditional even-odd preconditioning technique. These developments will make it easier to compute observables measured in JLab experiments from first principles.




Environment, Safety, Health & Quality

Stroke Awareness
The early warning signs of stroke are:

1. Numbness or Weakness: sudden numbness or weakness of the face, arm or leg, especially on one side of the body.
2. Confusion: sudden trouble speaking or understanding.
3. Eyesight: sudden trouble seeing in one or both eyes.
4. Dizziness: sudden trouble walking, loss of balance or coordination.
5. Headache: sudden severe headache with no known cause.

You can determine if someone is having a stroke by asking him or her to perform these three simple things: smile, raise both arms and speak a simple sentence. Problems performing any of these tasks could indicate the person is having a stroke and must get help immediately. In order to survive a stroke and minimize long-term disability, the person must be treated without delay; otherwise, severe disability or death could occur. Even if the symptoms only last a few minutes, seek medical attention at once by calling 911 or by going to your local emergency department. For more information on strokes, visit the American Stroke Association website.

Computing and Networking Infrastructure

Maintenance Day Set for October 20, 5-10 p.m.
The CNI group is planning a minor maintenance day next Tuesday from 5-10 p.m. During this outage, the group will shut down and relocate jlabs1, jlabs2 and the /scratch file server. Each outage should last no more than 15 minutes. There may also be some web server outages during this time. As before, each web server outage will last no more than 15 minutes. 


Performance Appraisals - Self Assessments Due Today
Today is the deadline for employees to forward self assessments to supervisors. The lab-wide goal is to have all appraisals completed by Dec. 16; the timeline is posted online. The online appraisal system is composed of a predetermined sequence of events and is user friendly. However, if you are new to the system or need a refresher, there is a tutorial slideshow and a frequently asked questions document. In addition, formal classes can be added by request. If you have specific questions, call Bruce Ullman at x7170 or Cassandra Andrews at x7068.

Access Your United Way Pledge Form Electronically
Donors can access the United Way pledge form electronically this year. Simply print the form available at this link, fill it out and send it with any check payments attached to Joshua Cameron, CEBAF Center, room B214, MS 12B by Monday, Nov. 2. As always with charitable donations, make a copy of the signed form for your records.

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.

Change in Main Phone Number for SURA Residence Facility
Effective immediately, the main phone number for the SURA Residence Facility is 757-223-1167. The fax number, 757-223-5430, remains unchanged. Users of the old number, x7460, will be transferred to the current Residence Facility phone number until Dec. 31. The Residence Facility offers overnight room accommodations for the JLab user community, visitors and guests. For information regarding room reservations, visit the facility's website.

CAD Design and Engineering Experts Needed
For the second consecutive year, JLab will support NASA Knight Team 122 in the FIRST (For Inspiration and Recognition of Science and Technology) Robotics Competition. A few expert CAD Design and Engineering volunteers are needed for the program. The CAD systems will be Autodesk Inventor (and maybe some PRO-E). The group will meet for a couple of hours per week between now and the end of the year. The contest kicks off at the Virginia Air and Space Center on Jan. 9. The team will have until Feb. 23 to complete the robot and prepare for competition. The JLab CAD group will help the team develop models, drawings, pictures, etc. for the robot being constructed. If you are interested in volunteering, contact Jim Henry at x7718.

JLab's Safety Numbers

91 Days since Last Recordable Accident (JLab record: 331)
399 Days since Last Lost Workday Accident (JLab record: 676)

JLab Calendar of Events

Oct. 15: Safety Shoe Vendor onsite
Oct. 20: Science Series Lecture - The Founders of Modern Astronomy
Oct. 28: William F. Brinkman, Director of DOE's Office of Science, visits JLab
Nov. 1: Daylight Saving Time ends
Nov. 12: Safety Shoe Vendor onsite
Nov. 16: Women in Science and Engineering Workshop
Nov. 24-25: Thanksgiving holidays - JLab closed
Dec. 10: Safety Shoe Vendor onsite
Dec. 24 - Jan. 1: Winter holidays/Shutdown days - JLab closed