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In this issue:
Symmetry Explains It in 60 Seconds: Scintillators
Improve Your Meetings in About an Hour
Colloquium Today: Home Energy Management—Smart Grid Meets the Internet

SLAC Today

Monday - October 4, 2010

Symmetry Explains It in 60 Seconds: Scintillators

(Image: Sandbox Studios.)

Scintillators are transparent materials that allow scientists to detect particles and other forms of radiation. When radiation hits a scintillator, the material absorbs some of its energy and makes it visible by emitting a flash of light. Even the tiniest amount of scintillation can trigger a signal in one of the state-of-the-art photodetectors that are attached to the edges of the scintillator.

Scintillation detectors have a wide array of applications, such as medical imaging, baggage scanning, oil exploration, monitoring of nuclear power stations, and—of course—particle physics.

Many types of transparent materials serve as scintillators, including plastics, liquids, crystals, and gases. One common, inexpensive material used in plastic scintillators is polystyrene, the plastic used in CD and DVD cases and many other consumer products.

Pure polystyrene is not an efficient scintillator. To improve its performance, scientists blend polystyrene with two fluorescent compounds. The first compound absorbs the radiation energy deposited in the polystyrene. It passes that energy along to the second compound, causing it to emit visible flashes of light. The two-step process efficiently converts radiation from X-rays and high-energy particles into visible light that can be easily detected. By adding different compounds, scientists can make the scintillators emit light in various colors.

Discuss, Discuss... Disgusted?
Improve Your Meetings in About an Hour

Two weeks ago John Schmerge and his technical leadership team from the Stanford Synchrotron Radiation Lightsource experienced a one-hour meeting training. Their meetings were OK, but there had been enough indicators that pointed to a need and the desire to make them better.

"We did not learn any drastically new information," Schmerge said, "but it was great to see it all in a consistent framework. We have already implemented a few suggestions and gotten a lot of positive feedback. People have noticed the difference and commented on it. It is recognized as new and useful. We're happy."

Participants are asked to consider three questions in advance of the training: What are aspects of horrible meetings? How do you personally contribute to bad meetings? What are the attributes of ideal meetings?

If you would like to consider a one-hour training session for your department or group, or lead a working group that has regular meetings, please contact Frank Topper (x3024). For a few meeting-making tips, see "The Lab Has an Agenda. Why Doesn't Your Meeting?"

Colloquium Today: Home Energy Management—Smart Grid Meets the Internet

(Image - SLAC Colloquium banner)

This afternoon at 4:15 in Panofsky Auditorium, Ben Lenail, distinguished visiting scholar at Media X at Stanford University, will present "Home Energy Management: Smart Grid Meets the Internet."

In the Fall of 2009, Stanford won a $7M grant from ARPA-Energy to develop and test new methods for getting residential energy consumers more engaged in conservation. Stanford is bringing together new insights in technology, pricing and behavioral economics, user interfaces and social networking to trigger and sustain long-term energy efficiency in the home—as an integral part of the digital lifestyle.

Lenail's work at Media X is focused on the ARPA-E research project for the residential smart grid and on using visual analytics with social network theory. Previously, Lenail spent fifteen years with Sun Microsystems in Menlo Park and Geneva, Switzerland, in a variety of R&D and corporate development positions. He worked for technology companies EDS and Accenture. Ben has an MBA from the University of Washington, a master's degree in manufacturing science from INSEAD and a bachelor's degree in economics from Sciences-Po Paris.

On Monday, November 1, Stanford particle physicist Giorgio Gratta will present "Geology of Neutrinos."


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