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arXiv · 2601.09906

A feasibility study for a Doppler Reflectometer System in the JT-60SA tokamak

D. Carralero·T. Happel·T. Estrada·T. Tokuzawa·J. Martínez·E. de la Luna·A. Cappa·J. García
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Abstract

In this work we present a study on the viability and practicality of installing a Doppler reflectometer (DR) system in the JT-60SA advanced tokamak. First, we discuss its scientific scope in the context of the JT-60SA research plan. We identify a number of fields in which a DR would be very relevant for the accomplishment of said plan and outline a scientific program for the diagnostic. Then, starting from a number of design hypothesis, we use a ray tracing code to carry out a feasibility study for a number of relevant scenarios and identify a geometric solution for the installation of a DR such that both core and edge can be probed in the prescribed wave number range, thus achieving the proposed scientific objectives. Finally, we perform a preliminary discussion on the different possibilities for a conceptual design (including a minimum viable system and a baseline system) and their requirements in terms of components and space. We conclude that a viable conceptual design could be carried out using a small fraction of a horizontal port, leaving room for additional diagnostic systems.

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D. Carralero, T. Happel, T. Estrada, T. Tokuzawa, J. Martínez, E. de la Luna, A. Cappa, J. García. 2026-01-14. A feasibility study for a Doppler Reflectometer System in the JT-60SA tokamak. https://doi.org/10.1016/j.fusengdes.2021.112803.

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