Jefferson Lab Weekly Briefs October 1, 2008
Jefferson Lab Weekly Briefs
October 1, 2008
12 GeV Upgrade
An important milestone for the 12 GeV Upgrade Project was achieved in September. The total design for the civil scope is complete. The major conventional construction will be the new experimental Hall D Complex, including the accelerator tunnel extension. The remaining scope is modifications to support facilities that are primarily associated with utility upgrades. There will be an addition to the Central Helium Liquefier (CHL) building to accommodate the additional refrigeration equipment. The low-conductivity water (LCW) and electrical distribution systems will be upgraded to support the accelerator operations at 12 GeV. The civil scope includes eight construction subcontracts to be placed during the next four years, with a total construction value of more than $25 million. The acquisition process of the first procurement, the Hall D Complex, continues. The Technical Evaluation Team completed assessment of the Offerors’ capability and discussions were initiated on Sept. 29.
L'Oreal USA Fellowships For Women in Science
The AIP State Department Science Fellowship Program
There was an unusual incident last Wednesday, Sept. 24, when a Central Helium Liquefier IOC (input/output controller) failed. This failure resulted in higher than normal gas discharge pressures that led to a pressure relief valve being activated several times in a short period of time. Unfortunately, this caused a 10 inch diameter high-pressure helium transfer pipe to rupture. The pipe was repaired in good order, and the CHL started the process of checking helium inventory prior to beginning 2 Kelvin pumpdown operations again. Aside from this incident, accelerator staff is concentrating on being ready for beam operations in about three weeks.
Free-Electron Laser (FEL)
FEL staff members are cooling down the FEL cryomodules and high-voltage processing the gun in preparation for running. The high-power RF (radiofrequency) window tests were successfully completed. FEL staff also installed mirrors and established aligned optical transport to the last lab with the new Optical Transport System.
A new method has been proposed for extracting neutron structure functions from inclusive structure functions of nuclei (arXiv:0809.4308 [nucl-th]). Unlike earlier approaches, the new method is applicable to both spin-averaged and spin-dependent structure functions and is able to reproduce known input functions of almost arbitrary shape to very good accuracy with only several iterations. The method is currently being applied to the analysis of JLab data on structure functions of deuterium and helium-3 nuclei.
The Installation and Vacuum group has been performing acid flushing of all power supplies in the beam switchyard service building and installing additional LCW taps in Hall C. Alignment and Metrology group members completed the initial alignment of the Hall C Spin Asymmetries of the Nucleon target (SANE: E07-003) and the Hall A Transversity target (E06-10/E07-013).
Environment, Safety, Health & Quality
Over the past three months, the site has experienced a number of near-miss safety incidents involving pressurized piping, electrical components, wild animals and slips, trips and falls. Unfortunately, we've also experienced a severe injury. An important correlation exists between these events; they were reported, investigated and analyzed. Because of that, we were able to learn from them and apply corrective and preventive actions site-wide.
The most important component of these investigations is the initial employee notification to their supervisor. For instance, if the recent slip, trip and fall incidents had not been reported, the hazard would not have been identified as a site-wide issue. However, our colleagues presented the information, which then allowed lab management to identify this as a hazardous trend. Facilities Management is currently surveying the entries and exits throughout the site to identify whether non-skid material is appropriate to mitigate the risk. Therefore, the entire site is now safer for all of us, simply because our colleagues took the crucial first step of reporting the events.
In summary, our most important objective is to work safely. Sharing information that could prevent future incidents or injuries plays a critical role in that objective.
Computing and Networking Infrastructure (CNI)
The CNI group has scheduled a maintenance period from 5-10 p.m. Tuesday, Oct 7. The central login servers, jlabl1 and jlabs1 will be down while they are moved to a new network. Jlabl1 will be rebuilt to use Redhat Enterprise Linux 5, so it will be down for an hour or so. The FEL networks will be down for about 30 minutes for network switch code upgrades; expect connection problems during that time. Linux and Windows patches will be pushed out to desktops and servers. Computers users with these CUE systems should plan on rebooting their desktop system(s) on Wednesday to complete the installation.
Blood Drive Set for October 7
Excess-Freestock Furniture Moves to New Building
$4-off Coupons for State Fair Ride Wristband
Friday Deadline for Entry in the JLab 2008 Fall Golf Tournament!
JLab's Safety Numbers
21 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
Oct. 1-4: Workshop on Sources of Polarized Electrons and High Brightness Electron Beams (PESP2008)