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Galayda to Head New LCLS Division
By Shawne Neeper
To build the world’s
fastest and shortest-wavelength x-ray laser, SLAC created a new Linac
Coherent Light Source (LCLS) Division and named John Galayda as its
Associate Director. Galayda brings nearly three decades of hands-on
experience with accelerator-based light sources to this project to
create the first-ever linac x-ray laser.
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John Galayda, Associate
Director for the LCLS Division (Photo by
Diana Rogers) |
After three years of
planning the LCLS facility in collaboration with scientists at UCLA and
Los Alamos, Livermore, Argonne and Brookhaven National Labs, Galayda
will oversee the construction phase, guiding the laser’s growth from the
drawing board into a new national user facility, similar in operation to
SSRL. The newly-established LCLS Division will operate alongside the
existing divisions at SLAC from initial setup and equipment procurements
in 2004-05 through construction in 2005-08.
LCLS will use the last
kilometer of the linac to speed tightly-packed bunches of electrons
towards a 175-meter gauntlet of specially designed magnets. As these
‘undulator magnets’ bounce the electrons side-to-side, the electrons
will emit x-rays into underground experimental stations. The x-rays are
10 billion times brighter and one thousand times shorter in duration
than previously possible and promise real-time views into atomic and
magnetic acrobatics. The femto-second x-ray pulses could even capture
atoms shifting position and forming molecular bonds.
Construction of the
super laser will cost approximately $315 million, Jonathan Dorfan said
at his State of the Lab address. The project calls for the addition of a
new electron injector branching into the two-kilometer point on the
linac. New concrete tunnels, to house the undulator magnets and
experimental facilities, will replace the current Final Focus Test Beam
(FFTB) tunnel, and extend from the end of the current linac past the PEP
Ring Road. “Since LCLS will use space currently dedicated to FFTB,
proposals for FFTB replacements are in the works,” Dorfan said. “We
require here the talents of the full lab.”
The LCLS Division will
draw from existing SLAC personnel as well as external contractors and
collaborators. That talent will have the leadership of an individual
with exceptional experience.
“[Galayda] is a world
class physicist and brings to the LCLS a broad range of talents,” said
LCLS chief engineer Mark Reichanadter (SSRL/LCLS). “When you talk about
free-electron lasers and synchrotron radiation, he’s on the short list.”
LCLS is not the first
high-energy light source that Galayda has helped to develop, nor even
his second. Fresh from his graduate studies at Rutgers University in
1977—and inspired by a lecture from SSRL pioneer Herman Winick—Galayda
joined a new project to build the National Synchrotron Light Source at
Brookhaven.
“It was a small group.
Everyone did everything,” Galayda said. He was up to his elbows in
magnets, accelerator design and electron beam diagnosis until accepting
a position as division director for the new Advanced Photon Source (APS)
at Argonne in 1990. After 11 years with overall responsibility for
design, construction, operation and upgrading of the APS accelerator
systems, Galayda joined SLAC to help launch the LCLS in April 2001.
LCLS collaborations
span organizations and lab sites. Specialized x-ray transport optics and
diagnostics, under development at LLNL, must be optimized to deliver the
most useful images to users. And the laser’s amazing brightness and
femto-second pulse duration will demand the best possible performance
from the SLAC linac.
“We’ll be relying
heavily on past experience with the linac,” Galayda said. “The extremely
short wavelengths of x-rays puts unprecedented demands on the beam
quality.”
A new electron
injector will create a high quality beam using an electron source based
on SLAC, Brookhaven and UCLA collaborative R&D. Once the injector shoots
electrons down the linac, the accelerator must compress the beam’s
electron bunches through two magnetic bunch compressors developed at
SLAC to generate the LCLS’s extremely short-duration x-ray pulses.
Once the system goes
on line—in 2009, if all goes as scheduled—users from around the world
can apply to perform experiments using the x-ray source. Several
experiments, looking at protein structures and magnetic behavior of
molecules, are already planned. But this is a technology with
unprecedented potential that will push into new experimental frontiers.
“Some experiments are
so hard that our outside partners will help us learn to do them,”
Galayda said. “A lot of the techniques are not yet developed.” Building
the LCLS is only the first part of the challenge. |
