Three SLAC scientists receive DOE early career research grants

Three scientists at the Department of Energy’s SLAC National Accelerator Laboratory will receive DOE Early Career Research Program grants for research to find evidence of cosmic inflation, understand how plasmas excite particles to high energies and develop a way to accelerate particles in much shorter distances with terahertz radiation.

ZEESHAN AHMED, FREDERICO FIUZA and EMILIO NANNI were among 59 scientists selected out of about 700 applicants for the grants, which were announced Aug. 9. They will receive about $500,000 per year for five years for salary and research expenses. You can see brief descriptions of the award winners’ work here.

The grants support the development of individual research programs of scientists who received their doctoral degrees up to 10 years earlier. Recipients must be full-time DOE national laboratory employees or tenure-track assistant or associate professors at  U.S. academic institutions. Their research topics must fall within one of six DOE Office of Science focus areas.

SLAC's 2017 DOE Early Career Award winners, from left: Frederico Fiuza, Emilio Nanni and Zeeshan Ahmed. (Dawn Harmer/ SLAC National Accelerator Laboratory)
SLAC’s 2017 DOE Early Career Award winners, from left: Frederico Fiuza, Emilio Nanni and Zeeshan Ahmed. (Image credit: Dawn Harmer/ SLAC National Accelerator Laboratory)

Ahmed, a project scientist and Panofsky Fellow at the Kavli Institute for Particle Astrophysics and Cosmology at SLAC, led the design, testing, construction and deployment of the SLAC and Stanford BICEP3 telescope at the South Pole in 2015 as a postdoctoral scholar on Chao-Lin Kuo’s observational cosmic microwave background (CMB) research team at Stanford.

BICEP3 belongs to the third generation of instruments scientists are using to look for patterns in the CMB as evidence of cosmic inflation – the rapid expansion of the early universe following the Big Bang.

“We invented that quantum leap from the second to third generation of BICEP telescopes, and a lot of the technology that went into it was developed at SLAC,” Ahmed said. “BICEP3 has been taking high-quality data and the highest throughput of data of this kind for the past two years. In a year or two, the data collected with BICEP3 will produce deep maps that surpass the sensitivity of all previous CMB maps for inflation science.”

Fiuza creates numerical experiments in plasma physics as a staff scientist and leader of the theory group in the lab’s High Energy Density Science division.

In this role, he models processes in plasma, or ionized gas, that accelerate particles to high energies. The work has a wide range of applications, from illuminating astrophysical phenomena to exploring controlled fusion energy and shrinking particle accelerators for medical therapy.

“In addition to using simulations, I like to work very closely with experimental teams and design laboratory experiments where these models can be verified and we can test our predictions,” Fiuza said. “Basically, we use high-power lasers to heat matter to high energies, dissociate the electrons from the atoms and explore the physics of the resulting sea of charged particles.”

The simulations he builds capture the fundamental physics of plasmas at small scales. The very small-scale physics is particularly demanding to model, Fiuza said, and there’s still quite a bit researchers don’t understand.

Nanni is an associate staff scientist in the lab’s Technology Innovation Directorate (TID), where he is working on ways to accelerate electrons to high energies in much shorter distances than possible today.  This particular approach uses terahertz radiation – a wavelength that falls between visible light and radio waves – to accelerate electrons through finely milled metal structures (a dozen of the experimental prototypes fit in a hand). But there are a number of challenges to overcome before the technology can be scaled up to high energies and leave the lab bench for deployment in the wider world.

“We’re trying to shrink the size of accelerators for a whole host of applications, from experiments in high-energy physics, biology and chemistry to new tools for medical treatment,” Nanni said.

“Terahertz radiation is at a sweet spot, where its wavelength is short enough to potentially achieve high gradients – high rates of acceleration in a short distance – at a frequency where metal structures are highly conductive. It can also offer very high pulse rates. That’s especially important to SLAC because we would like to be able to use it in experiments at the lab’s Linac Coherent Light Source X-ray free-electron laser.” LCLS is a DOE Office of Science User Facility.

Read more about these SLAC scientists and their projects.