Massachusetts Institute of Technology (MIT) graduate student Hong Sio has gotten used to being somewhere else. His research as part of the High-Energy-Density Physics (HEDP) team at MIT’s Plasma Science and Fusion Center (PSFC) has rotated him from his Albany Street home facilities in Cambridge, Massachusetts, to California for projects on NIF and to New York for work on the OMEGA laser at the University of Rochester.
“I spent 120 days in hotel rooms last year,” he laughs. “Four months on the road.” All this travel has been necessary to support the kind of research that recently earned his fusion diagnostic a spot on the cover of an American Institute of Physics journal.
Sio, a participant in the NIF-MIT PhD Thesis Program, has been taking significant journeys since the age of 10, when his family emigrated from Macau to the United States, settling in southern California. Sio credits a high school summer program at UC Irvine with cementing his interest in science and specifically fusion, a potential source of abundant energy that has been an elusive goal of scientists for decades.
“UCI has an underground, research-grade nuclear reactor for producing medical isotopes—not meant to produce power, but still a really nice reactor,” he says. “Touring that facility made an impression on me. It made me think about how we generate electricity. It made me think about how we are going to generate electricity 30, 50 years from now.”
Sio continued his interest in energy research as a physics major at Harvey Mudd College in Claremont, California. He worked at the department’s high-intensity laser lab, which deepened his interest in lasers, fusion, and graduate study in physics. When he interviewed at MIT with HEDP division head Richard Petrasso, Sio had found a situation, and a research group, that “checked off all the boxes.”
“I thought, ‘Well, this group shoots lasers at things; this group works on fusion. What’s there to think about?’” And his decision was made.
The decision immersed him in inertial confinement fusion (ICF) research and has led to his particle x-ray temporal diagnostic (PTXD) being featured on the cover of the AIP Review of Scientific Instruments. Sio describes the ICF process:
“At the simplest level, we fill a tiny capsule with fusion fuel and fire many lasers at it simultaneously, compressing and heating the fuel. The hotter and more dense the fuel becomes, the more fusion reactions are generated.”
Researchers measure the nuclear products from these fusion reactions with special diagnostics in order to understand what’s happening in the capsule and improve performance. Sio is responsible for the magnetic particle time-of-flight (magPTOF) diagnostic on NIF (see “Measuring NIF Implosions with a Bang”). A project worked on by Hans Rinderknecht—a graduate of the NIF-MIT PhD program—when he was part of the MIT HEDP team, the diagnostic simultaneously measures shock and compression bang times—the moments of peak thermonuclear burn during ICF implosions. Being able to directly measure the shock and compression bang times helps researchers understand the physics involved in ICF implosions and provides necessary feedback for the next experiments.
“NIF is the most energetic laser facility in the world,” Sio says. “OMEGA is the second largest laser facility in the U.S. The opportunity to be so deeply involved at these world-class facilities as a graduate student is nothing short of remarkable.”
A recipient of the Department of Energy National Nuclear Security Administration (NNSA) Stewardship Science Graduate Fellowship, Sio will present his most recent research at NNSA headquarters in Washington, D.C., on May 9.
Sio anticipates graduating from MIT in the fall of 2017 and hopes to continue contributing to ICF fusion research, possibly as a postdoc at MIT, or at other national ICF facilities such as NIF or OMEGA, where his time on the road already has made him a familiar and welcome addition.
—Paul Rivenberg, PSFC
Six LLNL employees who work in the NIF & Photon Science Directorate participated in the 2017 edition of the Tri-Valley Expanding Your Horizons Conference on Feb. 25. The annual conference is geared to increase interest and foster awareness of careers in science, technology, engineering and mathematics (STEM) and to provide opportunities for young women to meet and interact with positive role models who are actively engaged in STEM-related careers.
The event drew about 300 young women in grades 6 to 9 to Diablo Valley College in San Ramon, California. The theme was “Trailblazing Your Future.” Attendees participated in two hands-on workshops and a special group activity, ate lunch with the presenters, and attended a career fair/science expo.
The conference was organized by LLNL, Sandia National Laboratories/California, Diablo Valley College San Ramon Campus, and the American Association of University Women.