A program written by Idaho National Engineering and Environmental Laboratory scientist Dave Dahl is helping solve mysteries from this side of the Solar System to its far reaches.
Three instruments now hurtling toward Saturn aboard the spacecraft Cassini will analyze cosmic dust and the atmosphere of Titan, Saturn's largest moon. Dahl's award-winning ion optics simulation program, SIMION for the PC, helped design the instruments. Here on Earth, other machines with ion optics elements designed in part by SIMION analyze environmental contaminants, decode DNA, and even uncover illegal drugs in urinalysis samples. SIMION has also been used to analyze components used in semiconductor manufacturing, indirectly improving the production of the very computers it runs on.
"It's kind of pervasive," says Dahl, a Lockheed Martin Idaho Technologies Company consulting engineer/scientist in the Chemical and Biological Sciences Department of the INEEL.
SIMION is so pervasive, and so influential, that the American Society for Mass Spectrometry recognized that "the application of SIMION has been invaluable to the design of mass spectrometers (the kinds of machines that SIMION simulates) for the last decade." The Society awarded Dahl its 1998 ASMS Award for a Distinguished Contribution in Mass Spectrometry.
Dahl designed SIMION to be an "enabling technology." Because the program is very user-friendly and intuitive, it helps people simulate the ion optics of instruments creatively and explore options they may not have been able to conceive without SIMION's help.
He feels that creating enabling technology is a particularly appropriate niche for a national lab. "This represents exactly the kind of thing a national lab ought to be doing," he says, "producing, developing and vigorously proliferating technology so that the maximum number of people will benefit from the taxpayer's investment."
SIMION's beauty lies in its intuitiveness. The program makes ions coursing through electromagnetic fields as easy to visualize as golf balls rolling across a putting green. The user chooses some ions, chooses a field to simulate, finds a comfortable viewing perspective, and lets the ions fly. The simulated ions, whose "flight" paths the user can trace mimic real ions inside a mass spectrometer. Mystery ions, whether in cosmic dust, environmental contaminant samples, or a drug-user's bodily fluids, can be identified by mass spectrometers based on how the particles move through the machine.
Dahl's SIMION odyssey began in 1985, when he re-wrote the original Australian version of the program. He made it compatible with personal computers, re-wrote the user interface, and improved the numerical methods that the program uses to calculate each ion's trajectory. The program was passed from scientist to scientist around the world, and over the years successive versions of the program have gained a widespread user community.
Each generation of SIMION "and he is now on Version 6" has been faster and more powerful. Dahl says, "This is an example of what you can accomplish if you stick with something for a long time."
To read more about this and other award-winning research at the Idaho National Engineering and Environmental Laboratory, visit our Web site at http://www.inel.gov. Read more about SIMION at http://inelext1.inel.gov/science/prestige.nsf/ineel/dahl.
Media contact: Teri Ehresman, (208) 526-7785, ehr@inel.gov Laura Helmuth, (208) 526-0063, helmll@inel.gov 98-62