Martin Greenwald

Martin Greenwald

Deputy Director, Senior Research Scientist





University of California at Berkeley, PhD Physics (1978)
University of California at Berkeley, MA Physics (1975)
Massachusetts Institute of Technology, BS Physics (1973)
Massachusetts Institute of Technology, BS Chemistry (1973)


Plasma physics; magnetic confinement fusion; turbulence and transport; data management and computing.


Dr. Greenwald is Deputy Director and head of the Office of Computer Services for MIT's Plasma Science & Fusion Center (PSFC).

Since joining the Plasma Fusion Center, Dr. Greenwald has  conducted physics research on the Alcator A, C, and C-Mod tokamaks, including  studies of energy and particle transport, pellet fueling and density limits.  His recent work has focused on  the role of critical gradients in determining plasma temperature profiles, on the EDA H-mode regime, and on the role of turbulent transport in determining the tokamak density limit.  This latter work is aimed toward defining a "first principals" theory for the limit with the long term goal of obtaining reliable predictions and extrapolations to future machines.

Dr. Greenwald's work in pellet fueling on Alcator C included the discovery of a new regime of enhanced energy and particle confinement. This was the first attainment of an internal transport barrier in a tokamak which is recognized as one of two generic approaches (along with H-Mode) to improving tokamak confinement.  Because of the correlation with peaked density profile, the work spurred interest in the i or Ion Thermal Gradient driven (ITG) mode, now believed to be the principal mechanism for anomalous transport in tokamaks.


United States Patent 4,899,100 - Microwave measurement of the mass of frozen hydrogen pellets.
Assignee: The United States of America as represented by the United States (Washington, DC)
Appl. No.: 226571
Filed: August 1, 1988


Chilenski, M.A.,  Greenwald, M.; Marzouk, Y.; Howard, N.T.; White, A.E.; Rice, J.E.; Walk, J.R.  “Improved profile fitting and quantification of uncertainty in experimental measurements of impurity transport coefficients using Gaussian process regression”, Nuclear Fusion 55, 023012, 2015.

M. Greenwald et al., “20 Years of Research on the Alcator C-Mod Tokamak”, Phys. Plasmas 21, 110501, 2014.

N. T. Howard, A. E. White, M. Greenwald, C. Holland and J. Candy, “Multi-scale gyrokinetic simulation of Alcator C-Mod tokamak discharges”, Phys. Plasmas 21, 032308, 2014.

M. Greenwald et al., “Overview of experimental results and code validation activities at Alcator C-Mod”, Nucl. Fusion 53, 104004, 2013.

M. Greenwald, T. Fredian, D. Schissel, J. Stillerman, “A metadata catalog for organization and systemization of fusion simulation data”, Fusion Engineering and Design 87, 2205-2208, 2012

M. Greenwald, “Tutorial: Verification and validation for magnetic fusion”, Phys. Plasmas 17, 058101, 2010.

M. Greenwald, R. Callis, D., W. Dorland, D. Gates, J. Harris, R. Linford, M. Mauel, K. McCarthy, D. Meade, F. Najmabadi, W. Nevins, J. Sarff, M. Ulrickson, M. Zarnstorff, S. Zinkle, FESAC report “Priorities, Gaps and Opportunities: Towards a Long-Range Strategic Plan for Magnetic Fusion Energy” DOE/SC-102 (2007).

M. Greenwald, “Density limits in toroidal plasmas”, Plasma Physics and Controlled Fusion, 44, pgs. R27-R80, 2002.

Talks & Media

Colloquium at Princeton Plasma Physics Laboratory, “20 + 1 years of research on the Alcator C-Mod Tokamak”, 3/18/2015

APS-DPP Review Talk “Twenty years of research on the Alcator C-Mod Tokamak”

Interview with Bruce Gellerman of NPR

Interview with National Academy of Engineering

Interview with Boston Business Network