Evolution of laser-driven magnetic fields from proton tomography

J. Griff-McMahon; V. Valenzuela-Villaseca; C. A. Walsh; S. Malko; B. McCluskey; K. Lezhnin; H. Landsberger; L. Berzak Hopkins; G. Fiksel; M. J. Rosenberg; D. B. Schaeffer; W. Fox

arXiv · 2603.18931

Evolution of laser-driven magnetic fields from proton tomography

J. Griff-McMahon·V. Valenzuela-Villaseca·C. A. Walsh·S. Malko·B. McCluskey·K. Lezhnin·H. Landsberger·L. Berzak Hopkins·G. Fiksel·M. J. Rosenberg·D. B. Schaeffer·W. Fox

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Abstract

Self-generated magnetic fields are commonly produced in high-power laser-plasma interactions. These fields can inhibit plasma heat-flow which makes them important in inertial fusion and controlled laboratory astrophysics experiments. In this work, we characterize the time evolution of self-generated magnetic fields using multi-view proton tomography at two timings. Tomographic reconstructions of the magnetic field show a clear transition from fields located close to the target at early time to more extended coronal fields at later time. The tomographic inversion and mesh radiography also enable a direct measurement of the magnetic-flux evolution. Comparisons with extended-MHD simulations show only moderate agreement in field structure, but good agreement in magnetic flux. This suggests that the field generation model is largely correct under these conditions, while the magnetic transport model requires additional development to reproduce the observed field structure.

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J. Griff-McMahon, V. Valenzuela-Villaseca, C. A. Walsh, S. Malko, B. McCluskey, K. Lezhnin, H. Landsberger, L. Berzak Hopkins, G. Fiksel, M. J. Rosenberg, D. B. Schaeffer, W. Fox. 2026-03-19. Evolution of laser-driven magnetic fields from proton tomography. https://arxiv.org/abs/2603.18931

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