Proton deflectometry analysis in magnetized plasmas: magnetic field reconstruction in one dimension

TL;DR

This paper presents a 1-D proton deflectometry reconstruction algorithm for magnetic fields in plasmas, validated against analytic solutions and applied to experimental data, including a hybrid technique using boundary conditions.

Contribution

It introduces a novel 1-D reconstruction algorithm for electromagnetic fields from proton fluence data, incorporating boundary conditions and source fluence constraints.

Findings

Reconstruction algorithm accurately recovers fields from analytic solutions.

Boundary conditions help constrain source fluence profiles.

Hybrid mesh-fluence technique improves field reconstruction in experiments.

Abstract

Proton deflectometry is increasingly used in magnetized high-energy-density plasmas to observe electromagnetic fields. We describe a reconstruction algorithm to recover the electromagnetic fields from proton fluence data in 1-D. The algorithm is verified against analytic solutions and applied to example data. Secondly, we study the role of source fluence uncertainty for 1-D reconstructions. We show that reconstruction boundary conditions can be used to constrain the source fluence profile, and use this to develop a reconstruction using a specified pair of boundary conditions on the magnetic field. From these considerations we experimentally demonstrate a hybrid mesh-fluence reconstruction technique where fields are reconstructed from fluence data in an interior region with boundary conditions supplied by direct mesh measurements at the boundary.