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In this issue:
Getting Good Science: Four Days in the Life of an SSRL User
Profile: Lance Dixon Searches for Answers
Stanford to Host Entrepreneurship Week

SLAC Today

Wednesday - February 14, 2007

Getting Good Science: Four Days in the Life of an SSRL User

(Photo - SSRL beamline)
Apurva Mehta and Jason Holt at SSRL Beamline 10-2.

Jason Holt has a very small problem on his hands. Holt, a researcher from Lawrence Livermore National Laboratory, has a batch of specially prepared carbon nanotubes, packed with hydrated ions of rubidium and bromine, and he wants to know something about how these ions behave confined inside the nanotubes. But these tiny, hollow pipes made of carbon, with walls only one atom thick, are far too small to see with ordinary microscopes.

Each year hundreds of scientists like Holt come to the Stanford Synchrotron Radiation Laboratory (SSRL) in search of answers in a variety of fields ranging from biology, to medicine, chemistry and environmental science, to name only a few. These investigators are what SSRL is all about. More than 50 laboratories around the world serve the scientific community with powerful experimental equipment that would otherwise be unavailable to individual researchers. Without access to these "lightsource" research facilities, many important scientific questions would go unanswered.

Holt's questions are more than just academic. Hydrated ions are charged atoms surrounded by a shell of water molecules, and they are found widely in nature. Hydrated ions of potassium, for instance, carry signals in the human nervous system. Nanotubes are similar in many ways to the channels that conduct ions in biological systems, and knowing how such ions behave inside nanotubes could aid in the design of new drugs or lead to new treatments for disease.  Read more...

(Weekly Column - Profile)

Lance Dixon Searches for Answers

(Image - Lance Dixon)Researchers are eager to begin analyzing the scores of data the Large Hadron Collider (LHC) will provide when it comes online later this year. They anticipate the LHC will push the boundaries of their understanding of the universe, revealing exciting new realms of physics. But given the complexity and abundance of data, it is not always clear what the results will actually mean. That's where theorists like Lance Dixon come in.

Dixon, a SLAC professor, is working with colleagues Carola Berger and Darren Forde at SLAC, Zvi Bern at University of California-Los Angeles, and David Kosower at France's Saclay, to find innovative methods to predict what scientists will see at the LHC. By comparing the predictions with real data, physicists will know better if they are indeed looking at fundamentally new phenomena. "We want to provide a tool for experimentalists," Dixon said. "It's to make sure we know we have new physics, and not get fooled by old physics."

Physicists use Feynman diagrams to calculate and visualize particle interactions, such as those at the LHC. Each diagram represents how each particle interacts, not only symbolizing the probability of each class of events, but also providing physical insight into the interaction. For more accurate predictions of complex events, the interaction can happen in a multitude of ways. A physicist who wants to know the details of important interactions at the LHC would have to calculate thousands of Feynman diagrams.

This process is highly inefficient, even for a computer. So Dixon and his colleagues are developing new mathematical and computational techniques to avoid tedious and unnecessary calculations. "We're trying to find a way to get to the answer without going into individual Feynman diagrams," he said.

Researchers have been working on this problem for more than 15 years, Dixon said. He expects most of the work to be in place in the next couple of years, when scientists hope the LHC will start unveiling new physics. Physicists hope the machine will help them prove the existence of the elusive Higgs boson, which is believed to be responsible for other particles having mass. The LHC could also find a smattering of exotic particles as predicted by a theory called supersymmetry. Additionally, researchers pose the possibility of discovering extra dimensions of space. The work of Dixon and his collaborators should help scientists discern whether they are looking at phenomena predicted by known theory, or if they are in fact making radical new discoveries.

Stanford to Host Entrepreneurship Week

(Logo - Entrepreneurship Week)
Do you have an innovative idea that can kick-start a new business or even change the world? If so, you can find out how you can start turning that idea into reality during Entrepreneurship Week at Stanford University.

From Saturday, February 24, to Saturday, March 3, Stanford will join over 200 universities across the country to celebrate national EntrepreneurshipWeek USA. With the theme "What's Your Big Idea? Take It On!" Stanford will offer a series of activities throughout the week to engage students and other members of the Stanford community in various dimensions of entrepreneurship.

Each day will feature a different focus area. Events will include presentations by prestigious speakers such as President Hennessy, Thomas Friedman, Steve Jurvetson, and Guy Kawasaki; ideas and examples of social and global entrepreneurship; roundtable discussions with business leaders; a showcase of successful Stanford technologies; a startup job fair; and mixers and receptions for venture capitalists, entrepreneurs, and students. The Innovation Challenge Showcase will feature presentations from competing student teams, with prizes awarded to the best and worst ideas. A venture capitalist event will allow students to present business ideas and receive feedback.

"This is a wonderful opportunity for people interested in innovation and entrepreneurship to network with other like-minded folks in the Stanford community," said Patrick Lui of SLAC's Technology Transfer Office. "The event offers a week-long glimpse into how an innovative idea may lead to entrepreneurship."

Events are free and open to the public, and SLAC employees and users are encouraged to attend. One exception is the venture capitalist event; it is open only to Stanford students who must apply in advance for a time slot.

The week-long program is organized by the Stanford Entrepreneurship Network and sponsored by Deloitte.

 A complete schedule and details are available here.

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