Jefferson Lab Weekly Briefs
December 16, 2009
12 GeV Upgrade
Rain has slowed progress at the Hall D construction site. A little over half of the mud slab has been placed, and the contractor has started forming the floor slab over this portion of the mud slab. The remaining portion of the mud slab should be placed by the end of this week. During the holiday shutdown, there will be an electrical outage at the northeast end of the accelerator site to facilitate two electrical connections for Hall D. One connection is the new 15 kilovolt switch at the existing unit substation north of the Free-Electron Laser Trailers to provide permanent power to the Hall D Complex, and the other is a temporary connection at Building 49 for construction operations power.
In Hall C, removal of the hypernuclear spectroscopy experiment, E05-115, equipment has been completed, and Q-weak installation is in full swing. The frame for the Q-weak toroidal magnet has been assembled and installation of the copper coils is starting. The Hall C users meeting will be held Jan. 22 and 23, 2010.
JSA/JLab Graduate Fellowship Program
JSA/JLab Sabbatical Support Program
Overall, the accelerator has been running well with high current and low trip rates. The injector laser spot was moved to boost the quantum efficiency. There were some repair activities. Last Wednesday, shunt adder MAN5R04 tripped off; on Friday, VBV2L17A would not open; and on Saturday, magnet RSEP9A tripped off and VBV2L17B would not open. All the faulty parts were replaced.
The FEL team made significant progress in a number of areas this week. The team successfully got H. Freund's Genesis/OPC (optical propagation code) running on a local machine and reproducing previous results. Genesis is simulation code for calculating the performance of FELs; this code was augmented with Freund's OPC. The team had a successful user run in pulsed laser deposition, the NASA/JLab boron nitride nanotube effort was cited in ScienceNow, the JLAMP proposal was finalized, and the team set up for a light pseudoscalar/scalar search run over the weekend before the machine shut down for two months for cryogenics work at the Central Helium Liquefier and installation of a new cryomodule.
In a new study by Theory Center staff and collaborators from Italy <arxiv:0911.1744 [hep-ph]>, the inclusive pion production reactions l p↑ → h X and l p↑ → jet + X are proposed as a test of factorization of transverse momentum dependent parton distributions (TMD) in processes with one hard scale. Predictions for the transverse single spin asymmetry, AN, are given for current and future experiments. Measurements at JLab and at a future electron-ion collider could be used to test the validity of this approach and of TMD factorization.
JLab's Safety Numbers
27 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
Dec. 16: Colloquium and Public Lecture, 3 p.m., CC auditorium
Environment, Safety, Health & Quality
According to the U.S. Fire Administration, holiday season fires kill more than 400 people, injure 1,650 and cause more than $990 M in damage. The USFA offers several simple life-saving steps you can take to ensure a safe and happy holiday. The tips address holiday greenery, lights, decorations, candles and smoke detectors. Here are some highlights from the steps and some additional safety tips:
Computing and Networking Infrastructure
During the first week of January, JLab's existing photocopiers will be replaced with new Xerox machines. The account codes used to access these systems will remain the same; however, it may be necessary to update your drivers to print to these devices. For a schedule of when the photocopiers will be relocated, as well as instructions on how to update your drivers, see the document posted online.
End-of-Year Dosimeter (Radiation Badge) Change-Out
Last Day for Key Validation
Last Day to Enter the Door and Cubicle Decorating Contest
Quark Cafe Hosts Holiday Bake Sale on Dec. 17
Quark Cafe Holiday Pie Orders Taken Through Dec. 18