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arXiv · 2606.15519

Axisymmetric reduction of the adjoint operator in ideal MHD equilibrium

Fumiya Tanji·Akinobu Matsuyama·Akio Sanpei·Sadao Masamune·Yasuaki Kuroe·Yuji Nakamura
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Abstract

Adjoint formulations of magnetohydrodynamic (MHD) equilibrium are presented for sensitivity analysis and optimization-based equilibrium calculations. We derive the adjoint of the three-dimensional equilibrium equations under fixed-boundary conditions and analyse its axisymmetric reduction. The reduced operator coincides with the perturbed Grad-Shafranov operator, thereby making explicit the connection between the threedimensional adjoint construction and the axisymmetric adjoint problem. The resulting framework provides a basis for relating adjoint structures in both axisymmetric and fully three-dimensional ideal MHD equilibrium.

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Fumiya Tanji, Akinobu Matsuyama, Akio Sanpei, Sadao Masamune, Yasuaki Kuroe, Yuji Nakamura. 2026-06-14. Axisymmetric reduction of the adjoint operator in ideal MHD equilibrium. https://arxiv.org/abs/2606.15519

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