6 papers · 1 filter
Compact quasiaxisymmetric stellarators, a near axisymmetric theory
Wrick Sengupta, Rogerio Jorge, Nikita Nikulsin +4
We develop a theory of ridges in compact stellarators with quasiaxisymmetry (QA). The equilibrium with finite plasma currents and pressure is modeled by ideal magnetohydrostatics (…
Optical analogy for stellarators: Ridges as caustics and coils as singularities
Wrick Sengupta, Stefan Buller, Rogerio Jorge +7
A common feature of most numerically optimized stellarator geometries is the presence of sharp ridges on outer flux surfaces, irrespective of the rotational transform. Despite thei…
Geodesic extended modes in low magnetic shear tokamaks and stellarators
Richard Nies, Felix Parra
Theories of ion-scale microinstabilities in tokamaks and stellarators typically assume that the passing electrons respond adiabatically due to their fast propagation speed. However…
The Geometry of Flux Surfaces with Quasi-Poloidal Symmetry
Rishin Madan, Wrick Sengupta, Elizabeth J. Paul +4
Quasi-poloidal (QP) magnetic fields have desirable properties for confining plasma: no radial drift of guiding centres (with positive implications for neoclassical transport), zero…
Periodic Korteweg-de Vries soliton potentials generate quasisymmetric magnetic field strength in a finite plasma-beta equilibrium
W. Sengupta, R. Madan, S. Buller +6
Quasisymmetry (QS) is a hidden symmetry of the magnetic field strength, B, that enables effective confinement of charged particles in a fully three-dimensional (3D) toroidal plasma…
Exploration of the parameter space of quasisymmetric stellarator vacuum fields through adjoint optimisation
Richard Nies, Elizabeth J. Paul, Dario Panici +2
Optimising stellarators for quasisymmetry leads to strongly reduced collisional transport and energetic particle losses compared to unoptimised configurations. Though stellarators…