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arXiv · 2508.17691

Design and initial results from the "Junior" Levitated Dipole Experiment

Craig S. Chisholm·Thomas Berry·Darren T. Garnier·Rodney A. Badcock·Gabriel Bioletti·Konstantinos Bouloukakis·Emily-Kei Brewerton·Mike A. Buchanan·Pierce J. Burt·Eleanor V. W. Chambers·Kris B. Chappell·Patrick Coulson·Ryan J. Davidson·Josh P. M. Ellingham·Piet Geursen·Kent Hamilton·Raymond Hu·Emily Hunter·Joseph P. Jones·Plaso Kusay·Zvonko Lazić·Bradley Leuw·Matthew Lynch·Ratu Mataira·Mick McCrohon·Les Meadows·Jack R. Morris·Ryan Nowacki·Jack V. Purvis·James H. P. Rice·Michael Rutten·Samuel Schimanski·Aaryan Sharma·Mohammad Siamaki·Alex Simpson·Thomas Simpson·Benjamin Smith·Eric Stiers·Emerson Swanson-Dobbs·Joe Todd·Eddyn O. P. Treacher·Jared D. Tyler·Sriharsha Venturumilli·Hubertus W. Weijers·Theodore Wordsworth·Nancy Zhou
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Abstract

OpenStar Technologies is a private fusion company exploring the levitated dipole concept for commercial fusion energy production. OpenStar has manufactured a new generation of levitated dipole experiment, called "Junior", leveraging recent advances made in high-temperature superconducting magnet technologies. Junior houses a ~5.6 T REBCO high-temperature superconducting magnet in a 5.2 m vacuum chamber, with plasma heating achieved via < 50 kW of electron cyclotron resonance heating power. Importantly, this experiment integrates novel high temperature superconductor power supply technology on board the dipole magnet. Recently OpenStar has completed first experimental campaigns with the Junior experiment, achieving first plasmas in late 2024. Experiments conducted with the full levitated system are planned for 2025. This article provides an overview of the main results from these experiments and details improvements planned for future campaigns.

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Craig S. Chisholm, Thomas Berry, Darren T. Garnier, Rodney A. Badcock, Gabriel Bioletti, Konstantinos Bouloukakis, Emily-Kei Brewerton, Mike A. Buchanan, Pierce J. Burt, Eleanor V. W. Chambers, Kris B. Chappell, Patrick Coulson, Ryan J. Davidson, Josh P. M. Ellingham, Piet Geursen, Kent Hamilton, Raymond Hu, Emily Hunter, Joseph P. Jones, Plaso Kusay, Zvonko Lazić, Bradley Leuw, Matthew Lynch, Ratu Mataira, Mick McCrohon, Les Meadows, Jack R. Morris, Ryan Nowacki, Jack V. Purvis, James H. P. Rice, Michael Rutten, Samuel Schimanski, Aaryan Sharma, Mohammad Siamaki, Alex Simpson, Thomas Simpson, Benjamin Smith, Eric Stiers, Emerson Swanson-Dobbs, Joe Todd, Eddyn O. P. Treacher, Jared D. Tyler, Sriharsha Venturumilli, Hubertus W. Weijers, Theodore Wordsworth, Nancy Zhou. 2025-08-25. Design and initial results from the "Junior" Levitated Dipole Experiment. https://doi.org/10.1016/j.fusengdes.2025.115551

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