Stationary density profiles in the Alcator C-mod tokamak

In the absence of an internal particle source, plasma turbulence will impose an intrinsic relationship between an inwards pinch and an outwards diffusion resulting in a stationary density profile. The Alcator C-mod tokamak utilizes RF heating and current drive so that fueling only occurs in the vici...

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Bibliographic Details
Main Authors: Scott, S., Kesner, Jay, Hughes Jr, Jerry, Mumgaard, Robert Thomas, Shiraiwa, Shunichi, Whyte, Dennis G, Ernst, Darin R.
Other Authors: Massachusetts Institute of Technology. Department of Nuclear Science and Engineering
Format: Article
Published: AIP Publishing 2018
Online Access:http://hdl.handle.net/1721.1/117087
https://orcid.org/0000-0003-4802-4944
https://orcid.org/0000-0002-3757-7730
https://orcid.org/0000-0002-9001-5606
Description
Summary:In the absence of an internal particle source, plasma turbulence will impose an intrinsic relationship between an inwards pinch and an outwards diffusion resulting in a stationary density profile. The Alcator C-mod tokamak utilizes RF heating and current drive so that fueling only occurs in the vicinity of the separatrix. Discharges that transition from L-mode to I-mode are seen to maintain a self-similar stationary density profile as measured by Thomson scattering. For discharges with negative magnetic shear, an observed rise of the safety factor in the vicinity of the magnetic axis appears to be accompanied by a decrease of electron density, qualitatively consistent with the theoretical expectations. © 2012 American Institute of Physics.