Quick Shot

A paper with lead author Peter Heuer (LLE) titled “Diagnosing magnetic fields in cylindrical implosions with oblique proton radiography ” was recently featured in the 2022 Early Career Author Special Collection of Physics of Plasmas. This paper presents proton-radiography measurements of magnetized cylindrical implosions conducted using the miniature magnetized liner inertial fusion (“mini-MagLIF”) platform on the Omega Laser Facility. The aim of the experiment was to measure the compressed magnetic field in the center of the implosion. However, analysis shows that these fields are obscured in the radiographs by self-generated magnetic fields in the coronal plasma produced by the laser beams that drive the implosion. An algorithm for generating synthetic proton radiographs from simulated fields was developed as part of this work and is now available as part of the open-source PlasmaPy project. The paper demonstrates how proton radiography at oblique angles can be used to measure azimuthally symmetric magnetic fields (which are undetectable at normal incidence) and concludes with recommendations for future experiments attempting to measure compressed magnetic fields in similar geometries. A group of researchers at LLE (L. Leal, J. R. Davies, E. C. Hansen, D. H. Barnak, J. L. Peebles, F. García-Rubio), LLNL (B. Pollock, J. Moody), and MIT (A. Birkel, F. H. Séguin) participated in this research and are co-authors on the paper.