A visualization of a Vlasov-Poisson simulation for a bump-on-tail instability problem, where a non-equilibrium distribution of electrons drives an electrostatic wave. The image shows particle density as a function of space and velocity. (Jeffrey Hittinger, Lawrence Livermore National Laboratory.)

Lawrence Livermore National Laboratory (LLNL) computational scientist Jeffrey Hittinger spends his life at extremes. On the job, he focuses on the physics of plasmas – searing clouds of speedy ions and electrons – for fusion energy. Outside work, he tends goal for a San Francisco Bay-area amateur hockey team. Instead of simulating flying particles, he’s blocking or catching flying pucks.

His two interests share a fast pace – extraordinarily fast for plasmas – and a challenging nature. “I’m attracted to difficult things,” Hittinger says, then laughs. “I’m a goalie, so maybe I’m interested in difficult, high-pressure things.”

Likewise, “we get to work on hard problems” at the lab’s Center for Advanced Scientific Computing (CASC), Hittinger says. And like pucks flying in from unexpected directions, “there are always new problems coming at you.”

Hittinger, a Department of Energy Computational Science Graduate Fellowship (DOE CSGF) recipient from 1996 to 2000, creates and tweaks computer algorithms that emulate and elucidate aspects of some of the world’s most complex experiments.

“It’s a mixture of my background and what I stumbled into when I came to the lab,” Hittinger says. As a graduate student, he used gas kinetics to model fluid mechanics. Lab personnel recruited him to improve fluid plasma models for laser-driven inertial confinement fusion (ICF), the goal of the National Ignition Facility (NIF).

In NIF’s stadium-sized building, powerful lasers shoot into a hohlraum, a thimble-sized container holding a BB-sized capsule of frozen hydrogen isotopes. The laser pulse generates powerful X-rays, imploding the pellet with tremendous pressure and heat. The hydrogen atoms fuse, releasing energy in a process similar to that powering the sun.

“For ICF to work, you have to get a nice, clean implosion,” Hittinger says. “To do that, you need all the energy you’re putting into the system to go where you want it to go.” Plasma, however, can interact with the lasers, scattering or reflecting them.

(Visited 1,595 times, 1 visits today)

Page: 1 2

Thomas R. O'Donnell

Thomas R. O'Donnell is senior science writer at the Krell Institute and a frequent contributor to DEIXIS.

Published by
Thomas R. O'Donnell

Recent Posts

Efficiency surge

A DOE CSGF recipient at the University of Texas took on a hurricane-flooding simulation and blew away limits on its… Read More

September, 2019

Robot whisperer

A DOE computational science fellow combines biology, technology and more to explore behavior, swarms and space. Read More

July, 2019

Labeling climate

A Berkeley Lab team tags dramatic weather events in atmospheric models, then applies supercomputing and deep learning to refine forecasts. Read More

July, 2019

Molecular landscaping

A Brookhaven-Rutgers group uses supercomputing to target the most promising drug candidates from a daunting number of possibilities. Read More

May, 2019

Forged in a Firestorm

A Livermore team takes a stab, atom-by-atom, at an 80-year-old controversy over a metal-shaping property called crystal plasticity. Read More

April, 2019

Visions of exascale

Argonne National Laboratory’s Aurora will take scientific computing to the next level. Visualization and analysis capabilities must keep up. Read More

March, 2019