By Jason Evans
Emily and Jarvis Caffrey are partners in more ways than one. The husband and wife duo are also research colleagues at Oregon State University’s Department of Nuclear Engineering and Radiation Health Physics (NERHP) and recent ARCS scholars — Emily for her master’s thesis measuring radiation doses in marine organisms, and Jarvis for his work aboard one of the only research vessels allowed inside the containment area of the Fukushima crisis, where he took radiation measurements with equipment developed at NERHP.
Emily and Jarvis Caffrey met working as student technicians with Oregon State’s Radiation Safety Office during the summer of 2008. They were married July 2011.
Emily’s research interests are in the fields of radioecology and radiobiology. “Essentially I study how radiation moves and interacts in biological and ecological systems.”
Her master’s research focused on creating voxel (short for volume pixel, the smallest distinguishable box-shaped part of a three-dimensional image) phantoms, or voxel-based models of marine organisms including the Pacific sanddab and the Dungeness crab. Emily and her colleagues used CT and MRI scans to create their three-dimensional models. These models are used to help calculate whether or how much radiation is present in non-human life forms under various exposure situations, she explained.
Currently, Emily is researching Carbon-14 emissions from nuclear power plants. “I am looking at sources of Carbon-14 in the environment; how it moves and how dose calculations can be optimized.”
Carbon-14 is unique among the building blocks of life because it cycles in plants, which photosynthesize and then respire it. Using a radiation detector called a liquid scintillation counter, Emily has analyzed vegetation samples grown downwind from nuclear power plants, and compared those with samples grown in control gardens, to determine if there is a significant difference in the amount of Carbon-14 present between the two locations.
Jarvis, on the other hand, discovered radiation health physics at Oregon State after considering a major in mechanical engineering. “I became very fond of radiation detectors,” he said, “and I just kind of geeked-out on it.” He eventually stumbled across work elsewhere in space radiation protection and was hooked.
Jarvis’ current research interests are primarily in space radiation protection and dosimetry, or devices for measuring doses of radiations. “It turns out that radiation dose is going to be a very serious limitation for any manned space exploration to Mars or long-term missions on the Moon,” he explained. “Space radiation dosimeters measure the amount of radiation absorbed by somebody or something, and are often fixed in a working area or worn by personnel who might be exposed to radiation,” he explained. “There is a lot of mystery about what kind of effects it has on astronauts. It’s a unique radiation environment above Earth’s atmosphere and magnetosphere, and it requires some specialized detectors.” This unique radiation environment is the subject of Jarvis’ published senior project.
Working with colleagues in oceanography, Jarvis also served as health physicist aboard a ship in the Pacific Ocean off the coast of Japan, as close as 18 miles from Fukushima following the March 2011 disaster. At the time, scientists had no idea how much radiation was released. Among other duties, Jarvis developed onboard radiation protection procedures and oversaw the deployment of the Oregon State scintillating sodium iodide crystal radiation detector. The team made transects to complete their sampling grid over the course of 15 days.
Nuclear engineering has become the focus of Jarvis’ graduate work, as he seeks to better understand other aspects of physics and engineering. “My heart is still in health physics and radiation detection,” Jarvis admitted. “I get that little kid feeling that there’s invisible stuff flying around that now I can see with these special tools, and understanding the physics behind it just makes it all the more fascinating.”
Jarvis is now designing a new detector that will work well for the space radiation environment and take advantage of cutting-edge technology coming out of other fields.
“As for a career, I’ve still got my eyes on getting to the Moon or Mars, but who doesn’t?” said Jarvis. “Something in the space program would be interesting; preferably something where I can experiment and try out ideas.” The research and teaching of academia draw him too, even at the high school level. “I think back to my teachers who really seemed to enjoy sharing their interests in science and remember how motivating that was for me to learn more,” he said.
Envisioning the future, Emily imagines working at the IAEA, a branch of the United Nations in Vienna, or a similar organization promoting the peaceful use of nuclear technologies, all the while conceding she wouldn’t turn down the opportunity to be an astronaut. “If one day we get to Mars and want to stay there, we are probably going to have to grow our own food. Growing plants, even from seeds that have been germinated in space, experiments along those lines would be fascinating.” Eventually Emily looks forward to spending time teaching at the college level.
Emily is originally from Santa Rosa, California. Jarvis was born and raised in Ashland, Oregon except for a stint in Colorado.
Fond of the outdoors, Oregon was a natural choice for both Emily and Jarvis to center their studies, and a perfect match once they discovered Oregon State. They enjoy reading and playing with their dog and cat when they find free moments at home in Corvallis. Together they love backpacking, hiking, diving and traveling. “We both love to go on road trips to national parks, and to meet new people.”