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Comment on "Solitonlike Solutions of the Grad-Shafranov Equation"

G. N. Throumoulopoulos·K. Hizanidis·H. Tasso
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Abstract

In the above entitled recent publication by Giovanni Lapenta [Phys. Rev. Lett. Vol 90, 135005 (2003) ] it is claimed construction of a new class of solitonlike solutions for the Grad-Shafranov equation in plane geometry. It is proved here that, because of the mathematically erroneous choice \nabla p= |Ψ|^2 Ψ\nabla Ψfor an analytic continuation of the poloidal magnetic flux-function Ψin the complex plane (p is the pressure), the cubic Schrödinger equation considered by the author is irrelevant to the equilibrium problem and the Grad-Shafranov equation.

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G. N. Throumoulopoulos, K. Hizanidis, H. Tasso. 2003-07-22. Comment on "Solitonlike Solutions of the Grad-Shafranov Equation". https://doi.org/10.1103/physrevlett.92.249501

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