Overall, the accelerator was running well, with low trip rates. Radiofrequency zone 2L21 caused beam to be unstable, and the zone was bypassed. Two shifts were spent for beam studies. Hall A Compton signal-to-noise ratio sometimes changed, which required fine-tuning of the beam.
The FEL team altered the drive laser approach for producing 40 picosecond bunches and substantially improved the phase stability. The team has been able to establish lasing that can be used for beam studies and user tests. The team has also been preparing for the JLab Open House.
Deep inelastic scattering in the saturation region (for small x and/or large nucleus) is described by the evolution of color dipoles. In leading order in the strong coupling constant, this evolution is governed by the non-linear Balitsky-Kovchegov equation; but to see whether this equation is relevant for future accelerators (like the proposed Electron-Ion Collider or the proposed LHeC), one needs to know how big the next-to-leading order (NLO) corrections are. A new review article <arXiv:1004.0057 [hep-ph]> summarizes the status of the NLO corrections to high-energy amplitudes in various theories, including QCD.
JLab's Safety Numbers
4 Days since Last Recordable Accident (JLab record: 331)
JLab Calendar of Events
April 28: Colloquium and Public Lecture
Environment, Safety, Health & Quality
There will be many temporary changes to the accelerator site, buildings and roads to support the Open House scheduled for May 1. If you have questions about the event, visit the Open House webpage. The Open House is addressed by ESH-10-021-OSP. Michelle Lechman, Open House Coordinator, is providing all tour escorts with a briefing of the safety aspects of the Special Event OSP and additional helpful material. All Open House volunteers, in unpaid or paid status, must attend the safety briefing and orientation. The last scheduled briefing will be held in the CEBAF Center auditorium on Thursday, April 29 at 3 p.m. A copy of the OSP and associated documents will be posted online after signatures are obtained and before the event. In addition, an e-mail will go out this afternoon highlighting road closures and disruptive setup activities for the Open House; it will also contain a map showing volunteer parking locations.
Volunteers are still needed; call Tina Menefee, Open House Volunteer Coordinator (x5490), if you can volunteer a few hours of your time. Among other important tasks, volunteers provide a continuous escort along the tour route to ensure that visitors stay in designated areas and follow the assigned route. Escorts answer questions and provide the visiting public with assistance and direction and contact security or medical services if needed. It is a very important role, and the Open House depends on its volunteers. If you are a volunteer, remember to bring a hat or umbrella, sun screen, comfortable clothes, suitable shoes and your volunteer T-shirt!
Accelerators for Nuclear Reactors Colloquium and Public Lecture Today at 4 p.m.
Open House Countdown
JAG Run-A-Round Volunteer and Event Registration Is Open
National Library Week
E-books from Springer, Wiley and CRC are a significant boost to library holdings; these books can be found in the online catalog using the search terms Springerlink, Wiley Interscience, or CRCnetBase. Also, Springer will provide staff members a personal copy of any e-book that Library Services has purchased (2005 - 2008), as long as it is a Springer imprint/publication and not longer than 800 pages. Users pay only $24.95 per copy. See the "Mycopy" icon at the top of the specific Springerlink page. For an example page, click here. For assistance, contact library staff at x7525 or x7524.