511 to 520 of 570 Results
Nov 27, 2018
Peter J. Catto, 2018, "Symmetric spectrum current drive due to finite radial drift effects", https://doi.org/10.7910/DVN/LWEJDP, Harvard Dataverse, V1
The drift surfaces of minority heated ions differ from flux surfaces due to finite poloidal gyroradius effects. As the minority poloidal gyroradius approaches radial scale lengths in the plasma the difference between drift and flux surfaces can modify the heating and lead to a symmetric spectrum minority counter-current being driven. In response,... |
J.D. Lore, M.L. Reinke, D. Brunner, B. LaBombard, B. Lipschultz, J. Terry, R.A. Pitts, Y. Feng, 2018, "3D simulation of H-mode plasmas with localized divertor impurity injection on Alcator C-Mod using the edge transport code EMC3-EIRENE", https://doi.org/10.7910/DVN/ON9P44, Harvard Dataverse, V1
Experiments in Alcator C-Mod to assess the level of toroidal asymmetry in divertor conditions resulting from poloidally and toroidally localized extrinsic impurity gas seeding show a weak toroidal peaking (~1.1) in divertor electron temperatures for high-power Enhanced D-alpha H-mode plasmas. This is in contrast to similar experiments in Ohmically... |
L. G. Suttle, J. D. Hare, S. V. Lebedev, A. Ciardi, N. F. Loureiro, G. C. Burdiak, J. P. Chittenden, T. Clayson, J. W. D. Halliday, N. Niasse, D. Russell, F. Suzuki-Vidal, E. Tubman, T. Lane, J. Ma, T. Robinson, R. A. Smith, N. Stuart, 2018, "Ion heating and magnetic flux pile-up in a magnetic reconnection experiment with super-Alfvénic plasma inflows", https://doi.org/10.7910/DVN/FR7CG2, Harvard Dataverse, V1
This work presents a magnetic reconnection experiment in which the kinetic, magnetic and thermal properties of the plasma each play an important role in the overall energy balance and structure of the generated reconnection layer. Magnetic reconnection occurs during the interaction of continuous and steady flows of super-Alfvénic, magnetized, alumi... |
Nov 2, 2018
David A. Gates, David Anderson, S. Anderson, M. Zarnstorff, Donald A. Spong, Harold Weitzner, G. H. Neilson, D. Ruzic, D. Andruczyk, J. H. Harris, H. Mynick, C. C. Hegna, O. Schmitz, J. N. Talmadge, D. Curreli, D. Maurer, A. H. Boozer, S. Knowlton, J. P. Allain, D. Ennis, G. Wurden, A. Reiman, J. D. Lore, Matt Landreman, J. P. Freidberg, S. R. Hudson, M. Porkolab, D. Demers, J. Terry, E. Edlund, S. A. Lazerson, N. Pablant, R. Fonck, F. Volpe, J. Canik, R. Granetz, A. Ware, J. D. Hanson, S. Kumar, C. Deng, K. Likin, A. Cerfon, A. Ram, A. Hassam, S. Prager, C. Paz-Soldan, M. J. Pueschel, I. Joseph, A. H. Glasser, 2018, "Stellarator Research Opportunities: A Report of the National Stellarator Coordinating Committee", https://doi.org/10.7910/DVN/ZQHDRE, Harvard Dataverse, V1
This document is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national... |
R. L. White, R. D. Hazeltine, N. F. Loureiro, 2018, "Symmetries of a reduced fluid-gyrokinetic system", https://doi.org/10.7910/DVN/9HF5L0, Harvard Dataverse, V1
Symmetries of a fluid-gyrokinetic model are investigated using Lie group techniques. Specifically the nonlinear system constructed by Zocco and Schekochihin (Zocco & Schekochihin 2011), which combines nonlinear fluid equations with a drift-kinetic description of parallel electron dynamics, is studied. Significantly, this model is fully gyrokinetic,... |
Silvia Espinosa, Peter J. Catto, 2018, "Theoretical explanation of I-mode impurity removal and energy confinement", https://doi.org/10.7910/DVN/1CM1DY, Harvard Dataverse, V1
Improved (I) mode operation maintains the beneficial high energy confinement of high (H) mode while also providing natural fueling to compensate for impurity removal. We show outward collisional radial impurity flux is the robust distinguishing characteristic between I-mode and H-mode, rather than the turbulent weakly coherent mode that is sometime... |
Nov 1, 2018
Peter J. Catto, Jungpyo Lee, Abhay K. Ram, 2018, "A quasilinear operator retaining magnetic drift effects in tokamak geometry", https://doi.org/10.7910/DVN/76HUGN, Harvard Dataverse, V1
The interaction of radio frequency waves with charged particles in a magnetized plasma is usually described by the quasilinear operator that was originally formulated by Kennel and Engelmann (Phys. Fluids vol. 9, 1966, pp. 2377-2388). In their formulation the plasma is assumed to be homogenous and embedded in a uniform magnetic field. In tokamak pl... |
Stanislav Boldyrev, Nuno F. Loureiro, 2018, "Calculations in the theory of tearing instability", https://doi.org/10.7910/DVN/MOCDDK, Harvard Dataverse, V1
Recent studies have suggested that the tearing instability may play a significant role in magnetic turbulence. In this work we review the theory of the magnetohydrodynamic tearing instability in the general case of an arbitrary tearing parameter, which is relevant for applications in turbulence. We discuss a detailed derivation of the results for t... |
R. Jorge, P. Ricci, N. F. Loureiro, 2018, "A Drift-Kinetic Analytical Model for SOL Plasma Dynamics at Arbitrary Collisionality", https://doi.org/10.7910/DVN/HZCZ0S, Harvard Dataverse, V1
A drift-kinetic model to describe the plasma dynamics in the scrape-off layer region of tokamak devices at arbitrary collisionality is derived. Our formulation is based on a gyroaveraged Lagrangian description of the charged particle motion, and the corresponding drift-kinetic Boltzmann equation that includes a full Coulomb collision operator. Usin... |
J. J. Ramos, 2018, "Kinetic-magnetohydrodynamic description of longitudinal sound waves in a collisionless, quasineutral plasma", https://doi.org/10.7910/DVN/2Q5YUA, Harvard Dataverse, V1
The time evolution of slow sound waves in a homogeneous, collisionless and quasineutral plasma, in particular their Landau damping, is investigated using the kinetic magnetohydrodynamics formulation of J.J. Ramos (J . Plasma Phys. vol. 81, 2015 p. 905810325; vol. 82, 2016 p. 905820607). In this approach, the electric field is eliminated from a clos... |
