Alcator C-Mod, MIT PSFC

The interior of Alcator C-Mod as seen from F port.

Robert Mumgaard, MIT

PSFC research recognized by IAEA and the journal, Nuclear Fusion


Two papers focused on studies in Alcator C-Mod are among eleven that have been shortlisted for the 2015 Nuclear Fusion Prize. The shortlisted papers, selected based on citation record and recommendation by the Board of Editors, are judged to be “those of the highest scientific standard,”  and are selected from the 2012 volume of Nuclear Fusion.

The shortlisted papers are:

“Scaling of H-mode threshold power and L-H edge conditions with favourable ion grad-B drift in Alcator C-Mod tokamak” whose lead author is former graduate student Yunxing Ma, currently working at ITER. Ma’s Nuclear Fusion paper presents results from his PhD thesis research, in which he characterized access to the high-confinement mode, or H-mode, in a tokamak operating under conditions relevant to next-step devices. The choice of plasma density has a sizable impact on H-mode access, and this paper both seeks an explanation for this behavior and for the first time quantifies that the optimum density for H-mode access increases with the magnetic field of the tokamak. This result, later confirmed on the JET device, has implications for projecting H-mode access to future devices such as ITER.   

“Tungsten nano-tendril growth in the Alcator C-Mod divertor”, whose lead author is PSFC Research Scientist Graham Wright. The paper reports on the growth of tungsten nano-tendrils ('fuzz') that has been observed for the first time in the divertor region of a high-power density tokamak experiment, and the conclusion that tungsten fuzz will grow in a tokamak and may have important implications for material erosion, dust formation, divertor lifetime and tokamak operations in next-step devices.

Established a decade ago, the Nuclear Fusion Prize is cosponsored by the International Atomic Energy Agency and IOP Publishing. The winner will be announced later this year.

The paper “I-mode: an H-mode energy confinement regime with L-mode particle transport in Alcator C-Mod” written by a team from the Alcator group with lead author Dennis Whyte won the 2013 Nuclear Fusion Prize. 

Topics: Magnetic fusion energy, Alcator C-Mod tokamak, Plasma material interactions