Lawrence Livermore National Laboratory



A Renaissance Man Driven to Excel

Physicist, classical historian, and weightlifter—could these seemingly disparate characters be the same person?  They could if the person is Roark Marsh, who feels if you do anything, you should do it well.

“If you’re not good at something, if you work hard at it, you can become good and do things you couldn’t imagine you’d be able to do,” he says, referring to his interest in physical activities such as weightlifting, CrossFit circuit training (a combination of running, rowing, gymnastics and weights) and yoga.

“I’m not very physically flexible,” he says, “but I’m broadening my perspective of what to get good at, which now includes yoga. There’s great satisfaction when you see improvement.”

Roark’s interest in physical activities came about in graduate school while he was working toward his PhD in accelerator physics at MIT (he had previously earned a BS in physics and a BA in both pure mathematics and classical studies [Greek and Latin literature] at UC Santa Cruz, all in 4 years).

“Grad school studies consume so much time, you need something else to keep you balanced,” he said.  An office mate got him interested in weightlifting and working out at lunchtime.  “The things that make you a good scientist make you good at anything. There’s an object lesson in practice—the harder you work, the better you get.”

The field of accelerator physics was, however, a rather lonely one for Roark. “I did everything,” he says, “running the machine, developing the theory, designing the experiments, analyzing the data, and defending the numbers.  There weren’t any other students.”

Consequently, one of the reasons he was drawn to LLNL after graduation was the opportunity to work in a group. “I had done some undergrad research at LLNL, so I knew the standard and culture and was interested in being a part of that, of doing collaborative work.”  The other reason was to get back to California.  “Four years in Boston was an adventure.  Six years was getting old—it’s cold there.  They say there are two seasons in Boston—winter and repairing the roads!”

At Livermore Marsh has been working on the mono-energetic gamma ray (MEGa-ray) project under the leadership of Fred Hartemann. MEGa-ray uses an X-band accelerator in combination with high-power diode-pumped laser technology to produce intensely brilliant gamma-ray beams that can excite specific isotopes of various elements and identify their contents at 50 times the penetration capability of x rays. MEGa-rays can be used for assaying nuclear wastes, detecting nuclear material at ports, and even for medical imaging.

Roark has been involved in design work. “We have all the components for a test station including support structure and modulators in Building 184.”  Under a Laboratory Directed Research and Development (LDRD) project, he has been working on a photoinjector that serves as the initial light source. “We’re trying to produce electron bunches and make them as high quality as possible,” he says. “They will interact with the laser and produce high-energy photons.”

Outside of work, Roark’s time is consumed by his young son, Theo. “It’s almost shocking how your priorities shift when you have a child, and how little you notice it.  I haven’t seen a movie in a long time. Instead, I play in a sandbox or go for a walk, and it’s great.” 

Travel was always important to Roark and his wife, Katie, whom he met in the 8th grade in middle school in Menlo Park and who also attended UC Santa Cruz, majoring in literature and philosophy.  They were both nervous about missing travel.  Recently, however, the three of them went to Spain.  “We just focused our planning a little differently, allowing more time between flights and staying away from big cities.  The people there were great with Theo.” 

Roark’s goals at the Lab are to advance MEGa-ray science, to have an X-band accelerator capability at Livermore, and to realize the possibilities of what that capability could bring to the community in useful applications.

In the meantime, he’s thoroughly enjoying not only the MEGa-ray project, but applying accelerator concepts to other efforts at the Lab.  “I like being able to give input, to think of new applications,” he says.  “It’s exciting to collaborate, to be a part of a culture in which there are a lot of interactive meetings where someone raises a concern, accepts feedback, and people work things out and find solutions as a group.  I hadn’t had that before.”