- Research Associate, Princeton University Plasma Physics Lab, 1973-1974
- Physicist, Fusion Energy Sciences Program, LLNL, 1974-present
- Associate Program Leader and MFE Theory Group Leader, LLNL, 1988-2006
Ronald Cohen is a theoretical and computational plasma physicist with general interests in plasma physics for magnetic fusion and heavy-ion fusion applications, accelerator physics, nonlinear dynamics, computational fluid dynamics, astrophysics, and space plasmas. Specific MFE plasma physics areas of concentration have included tokamak edge physics radio frequency-plasma interactions, magnetic mirror confinement, and spheromak physics. He ws co-PI of the team that won the Gordon Bell Prize for computational performance in 1999. He is a fellow of the American Physical Society, and has over 160 refereed publications.
I. Joseph, R.H. Cohen, and D.D. Ryutov, "Driving toroidally asymmetric current through the tokamak scrape-off layer to suppress edge localized modes",
R.H. Cohen, D.P. Grote, A. Friedman, and J.-L. Vay, "An Implicit ``Drift-Lorentz'' Mover for Plasma and Beam Simulations",
R.H. Cohen and X.Q. Xu, "Progress in Kinetic Simulation of Edge Plasmas", Contributions to Plasma Physics 48, 212 (July 2008) (invited review).
R.H. Cohen, B. LaBombard, D.D. Ryutov, J.L. Terry, M.V. Umansky, X.Q. Xu, S. Zweben, "Theory and Fluid Simulations of Boundary Plasma Fluctuations",
R.H. Cohen, D.D. Ryutov, G.F. Counsell, and P. Helander, "Current and Potential Distribution with Toroidally Asymmetric Biasing of the Divertor Plate",
R.H. Cohen and D.D. Ryutov, "Dynamics of an isolated blob in the presence of the X-point", Contrib. to
R.H. Cohen and D.D. Ryutov, "On the possibility of the sheath-driven, finite-beta modes localized near the divertor plate",
R.H. Cohen, A. Friedman, M. Kireeff Covo, S.M. Lund, A.W. Molvik, F.M. Bieniosek, F. P.A. Seidl, J.-L. Vay, P. Stoltz, and S. Veitzer, "Simulating Electron Clouds in Heavy-Ion Accelerators,"
R.H Cohen and D.D Ryutov, "Sheath Physics and Boundary Conditions for Edge Plasmas",
Shestakov, A. I., Cohen, R. H., Crotinger, J. A., LoDestro, L. L., Tarditi, A. and Xu, X. Q., "Self-Consistent Modeling of Turbulence and Transport,"
Cohen, R. H., Dannevik, W. P., Dimits, A. M., Eliason,D., Mirin, A. A., Zhou, Y., Porter, D. H. and Woodward, P. R., "Three-dimensional simulation of a Richtmyer-Meshkov instability with a two-scale initial perturbation."
Cohen, R.H., Ryutov, D.D., "Discrete symmetries in axisymmetric toroidal plasma confinement,"