5 papers
Symmetry-agnostic stellarators for collisionless confinement
W. Sengupta, A. Bhattacharjee, S. Buller
Quasisymmetry, omnigenity and piecewise omnigenity confine trapped particles by making the bounce action independent of the field-line label. Recent optimizations produce mixed-sym…
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…
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…
A Grad-Shafranov model for compact quasisymmetric stellarators
Nikita Nikulsin, Wrick Sengupta, Stefan Buller +1
A Grad-Shafranov equation (GSE) valid for compact quasisymmetric stellarators is derived by an asymptotic expansion around a vacuum field carried to first order. We obtain an equat…