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In this issue:
LCLS Undulators Installed and Ready for Beam
SLAC Library Task Force Seeks Your Input
Colloquium Today: Sidney Drell on Nuclear Arms Control

SLAC Today

Monday - March 30, 2009

LCLS Undulators Installed and Ready for Beam

The first 21 of 33 undulators in place in the LCLS Undulator Hall. (Photo by Mike Zurawel. Click for larger image.)

SLAC's linac started up again last Wednesday after three weeks' downtime to install 21 of the 33 undulator magnets that will help generate X-rays in the Linac Coherent Light Source. The LCLS commissioning team completed the installation and initial alignment with impressive speed, taking less than half the time allotted for the work. If all continues to go well, the linac's electron beam could make its first test run through the new undulators as soon as April 4.

Resting on their support girders in the LCLS Undulator Hall, these first 21 magnets make the LCLS the world's longest undulator, at 84 meters (276 feet). By June, the remaining 12 will be added to the Undulator Hall, bringing the total length, including short breaks between magnets, to 132 meters—about the length of a football field plus an extra 24 yards. In order to generate powerful, free-electron light from this string of undulator magnets, the electron beam brightness must meet a set of challenging criteria—the focus of the successful accelerator commissioning up to this point, starting with the new radio-frequency photocathode gun in April 2007. (See "Have Gun, Will Travel (at Light Speed).") In addition, the magnets that guide the beam must be aligned to extraordinary tolerance levels. At its highest performance, the beam must not deviate from a straight line by more than about 5 microns per 5 meters. Much effort has gone into preparing for this primary challenge, from careful initial survey methods in the Undulator Hall through high-precision magnet tuning and creation of a novel beam-based alignment strategy.  Read more...

SLAC Library Task Force Seeks Your Input

While the SLAC Library's public-use area is temporarily housed in the foyer of Building 50, the lab has an opportunity to explore and define how the library can best be organized to meet our current and future information needs.

Library use has changed tremendously in the last decade, particularly since most scientific journals and other useful information are easily accessible online. In addition, SLAC's science is evolving. In response to these changes, SLAC management has charged a new task force to recommend how best to meet SLAC's future library needs. The Library Task Force includes: Anders Nilsson (chair), Niels van Bakel, Patricia Kreitz, Nan Phinney, David Reis, Aaron Roodman and Robert Ruland. We would like to get input from all SLAC users and staff about their future needs for library collections, access and services.

Please take five minutes to answer the Task Force's online survey, now through April 20. Please also feel free to contact the task force members with your ideas and suggestions.

Colloquium Today:
Sidney Drell on Nuclear Arms Control

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This afternoon, SLAC Deputy Director Emeritus and Hoover Institution Fellow Sidney Drell will present, "Rekindling the Vision of President Reagan and General Secretary Gorbachev at Reykjavik: Steps Toward a World Free of Nuclear Weapons."

During the Cold War, the United States and the former Soviet Union relied on nuclear deterrence. In today's world, the accelerating spread of nuclear material, know-how and weapons present an increasing danger that nuclear weapons may be acquired by ruthless national leaders or suicidal terrorists. Under these circumstances, relying on thousands of nuclear weapons for deterrence is increasingly hazardous and decreasingly effective. What will it take to rekindle the vision of a world free of nuclear weapons, which Reagan and Gorbachev brought to their remarkable summit at Reykjavik in 1986? Can a worldwide consensus be forged on a series of practical steps to escape the nuclear deterrence trap?

Drell will discuss these issues, drawing on his long career as a scientist and leader in nuclear arms control. Drell has been a senior adviser to both the executive and legislative branches of the federal government on national security and defense issues for more than four decades. Among other honors, he received a MacArthur Fellowship in 1984 for his work in theoretical physics and international arms control, and in 2000, the Enrico Fermi Award for a lifetime of achievement in the field of nuclear energy.

Drell's colloquium begins at 4:15 p.m. today in Panofsky Auditorium. The event is free and open to all.

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