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In this issue:
LCLS Launches User Science Today
Around LCLS: The Ion Time-of-Flight Spectrometer
LCLS Cover Shot
eShop E-Commerce for Office Supplies Comes to SLAC Today
SLAC Green Note: What is a 'Spare the Air' Day?

SLAC Today

Thursday - October 1, 2009

LCLS Launches User Science Today

The AMO instrument scientists with the first LCLS users in the instrument hutch. From left to right: Christoph Bostedt, Steve Southworth, Linda Young, John Bozek, Steve Pratt and Yuelin Li. (Photo by Brad Plummer.)

SLAC's Linac Coherent Light Source opened for business this morning, and the first user experiment is now underway. As the world's first hard X-ray laser, the LCLS offers scientists the ability to study the fundamental behavior of atoms and molecules on unprecedented length- and time scales.

"The LCLS is performing beyond our expectations," said newly appointed LCLS Deputy Director Uwe Bergmann. "These first experiments are starting a new era of science, one that many researchers around the world have eagerly awaited."

This first user run will continue through mid-December, with 11 groups traveling to SLAC to use the Atomic, Molecular and Optical science instrument—the first of the six LCLS instruments to come online.

This week's experiment, led by Argonne National Laboratory's Linda Young, will provide a better understanding of how materials absorb very high intensity X-rays, by stripping atoms of their electrons from the inside out.

"It's exciting to be here," said Young, who is writing about her experience online. "The LCLS instrument scientists and their team have done so much work to get to this point. I'm very optimistic for our experiment."  Read more...

Around LCLS:
The Ion Time-of-Flight Spectrometer

(Photo by Karen Holtemann.)

The ion time-of-flight spectrometer, or ion TOF, is a measurement tool used in the Atomic, Molecular and Optical science instrument at the Linac Coherent Light Source. The ion TOF detects ions created by the intense LCLS laser pulses.

"It tells us about the charge states of the ionized atoms, like how many electrons were taken away from the atoms," said AMO instrument scientist Christoph Bostedt.

With this information, researchers can determine how many photons of laser light were absorbed by the atoms and how much energy was originally deposited into them from the laser. This spectrometer detected the result of the first test of the LCLS on a sample, which removed all ten electrons from neon atoms, and it will play a big role in the first LCLS user science experiments that begin today. 

(Image - Laser Focus World September 2009 cover)
(Image courtesy Laser Focus World. Photo on the cover by Brad Plummer, SLAC.)

LCLS Cover Shot

Another view on start-up of the Linac Coherent Light Source comes from the September 2009 issue of Laser Focus World. The cover story, "Photonic Frontiers: Linac Coherent Light Source Begins Operation," features several eye-catching illustrations of the sleek machine, including the cover photo by SLAC Communications Officer Brad Plummer (left). The story begins:

This month the SLAC National Accelerator Laboratory (Stanford, CA) will open the world's shortest-wavelength free-electron laser for use by guest scientists. First operated in April at 0.15 nm the Linac Coherent Light Source is the first free-electron laser to emit hard x-rays. Read more from Laser Focus World...

eShop E-Commerce for Office Supplies Comes to SLAC Today

The SLAC Purchasing Department and partners have launched a new tool for SLAC staff to obtain office supplies. Read more...

(Image - ISEMS leaves)

SLAC Green Note:
What is a 'Spare the Air' Day?

When air pollution levels are forecast to exceed state and federal health-based standards, a Spare the Air Alert is issued by the Bay Area Air Quality Management District. The BAAQMD issues both summertime and wintertime alerts under the Spare the Air Program.

According to the BAAQMD, in the summertime, ground-level ozone causes the most serious air-quality problems, with the major sources of Bay Area summertime air pollution being emissions from mobile sources such as cars, trucks, buses and equipment. Hot temperatures combined with lighter than usual winds can result in more pollutants near the ground.

The most significant action that people can take to reduce summertime air pollution is to drive less. See for everyday tips on sparing the air and SLAC's Alternate Transportation page for information on transport to and from SLAC.

You may sign up for online e-mail notifications of air quality information and receive advance notice on predicted Spare the Air Days through AirNow.


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