The most powerful X-rays on earth help Christopher Kim and his students gain insights at the atomic level

KEG Lab researchers Manny Vejar, left, and Fernando Silva load a sample for analysis by the synchrotron, which uses the brightest, most powerful X-rays on earth to provide a view of structures at the atomic level.

BEAM TIME Story & Photos By Dennis Arp Geochemistry students shine in the brightest rays of research.

Our story starts with undergraduate students running sophisticated tests using beams of the brightest, most intense X-rays on earth. But don’t worry, this tale has a happy ending.

Students in the Kim Environmental Geochemistry (KEG) Lab at Chapman University are thoroughly prepared to meet the challenge of such a high-level research opportunity. Professor Christopher Kim, Ph.D., the principal investigator who leads the lab, is an internationally recognized environmental geochemist who studies the impact of metal contamination in natural settings. He’s been using the synchrotron radiation testing facility in Palo Alto, California, since his own undergrad days at Stanford University, which operates the lab.

“With the synchrotron, we can probe the structure of our samples at the atomic level,” Kim explains. “We can identify trace concentrations of elements we’re interested in, and we can look at our samples in pretty much their native state. Th ere’s no other instrument that can do what the synchrotron can, with this degree of resolution and detail.”

KEG team student researchers learn fast that “beam time” is precious at the Department of Energy national lab. Th ey ready their samples weeks before fl ying to Northern California so they can optimize an intensive 72-hour research window that opens to very few undergrads. Aft er all, this is a facility three scientists have used for testing that led to Nobel Prize-winning breakthroughs.

“You’re a student, and you’re at this national lab with other scientists, doing research and collecting data,” says Jessika Valenciano, who

manages the KEG Lab. “It’s the kind of opportunity that sets the Chapman research experience apart.”

It’s common for new KEG Lab members to be intimidated when they fi rst use the synchrotron.

Who better to smooth the way than Kim? He is so widely recognized for his research that when environmental defense attorneys sought a judgment against a Swedish company that had shipped its mine waste to South America, they called on Kim as an expert witness. Closer to home, Kim’s research focuses on abandoned mines in California, where the same process that concentrated gold and other precious metals for miners to collect also concentrated arsenic and other hazardous metals.

“It turns out these mine wastes that are left over from the Gold Rush are this large environmental legacy that we’re having to deal with as potential health issues,” Kim says.

In support of Kim’s research, the KEG Lab receives funding from the U.S. Geological Survey and the National Science Foundation, which has presented Kim with a CAREER award – the NSF’s most prestigious recognition in support of early-career faculty.

For his part, Kim says that Chapman students will continue to play a vital role in the success of KEG Lab investigations.

“I benefi t because they come at these complex environmental geochemistry issues from diff erent angles,” he says. “Th ey benefi t because they get the opportunity to own their research – to develop an intuition that shows they’re becoming real scientists.”

As they gather data provided by the high-powered X-rays of the synchrotron, KEG lab students show they’re ready for next-level testing.

“Sometimes the only way to confi rm you can do the testing is for you to be tested yourself,” Valenciano says. “It’s empowering to have that opportunity to prove yourself.”

Student lab members such as Ryly Yee benefit from the beamline experience as they "develop an intuition that shows they're becoming real scientists," says principal investigator Christopher Kim, Ph.D.