2025/06/04 by Dominic Bernardi, Bernardi, Dominic, Yajie Yuan +3
Physics and Astronomy · #Dust and Plasma Wave Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Ionosphere and magnetosphere dynamics #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.2506.04175
openalex publication_date 2025/06/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Fast magnetosonic waves are one of the two low-frequency plasma modes that can exist in a neutron star magnetosphere. It was recently realized that these waves may become nonlinear within the magnetosphere and steepen into some of the strongest shocks in the universe. These shocks, when in the appropriate parameter regime, may emit GHz radiation in the form of precursor waves. We present the first global Particle-in-Cell simulations of the nonlinear steepening of fast magnetosonic waves in a dipolar magnetosphere, and quantitatively demonstrate the strong plasma acceleration in the upstream of these shocks. In these simulations, we observe the production of precursor waves in a finite angular range. Using analytic scaling relations, we predict the expected frequency, power, and duration of this emission. Within a reasonable range of progenitor wave parameters, these precursor waves can reproduce many aspects of FRB observations.