Laser-Driven, Ion-Scale Magnetospheres in Laboratory Plasmas. I. Experimental Platform and First Results

Abstract

Magnetospheres are a ubiquitous feature of magnetized bodies embedded in a plasma flow. While large planetary magnetospheres have been studied for decades by spacecraft, ion-scale "mini" magnetospheres can provide a unique environment to study kinetic-scale, collisionless plasma physics in the laboratory to help validate models of larger systems. In this work, we present preliminary experiments of ion-scale magnetospheres performed on a unique high-repetition-rate platform developed for the Large Plasma Device (LAPD) at UCLA. The experiments utilize a high-repetition-rate laser to drive a fast plasma flow into a pulsed dipole magnetic field embedded in a uniform magnetized background plasma. 2D maps of magnetic field with high spatial and temporal resolution are measured with magnetic flux probes to examine the evolution of magnetosphere and current density structures for a range of dipole and upstream parameters. The results are further compared to 2D PIC simulations to identify key observational signatures of the kinetic-scale structures and dynamics of the laser-driven plasma. We find that distinct 2D kinetic-scale magnetopause and diamagnetic current structures are formed at higher dipole moments, and their locations are consistent with predictions based on pressure balances and energy conservation.

References in corpus (7)

• First observation of a mini-magnetosphere above a lunar magnetic anomaly using energetic neutral atoms
• Exploiting multi-scale parallelism for large scale numerical modelling of laser wakefield accelerators
• Mini-magnetospheres above the lunar surface and the formation of lunar swirls
• Hybrid simulations of mini-magnetospheres in the laboratory
• Formation of collisionless shocks in magnetized plasma interaction with kinetic-scale obstacles
• Laboratory model of magnetosphere created by strong plasma perturbation with frozen-in magnetic field
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Cited by in corpus (9)

• Time-resolved velocity and ion sound speed measurements from simultaneous bow shock imaging and inductive probe measurements
• The structure of 3D collisional magnetized bow shocks in pulsed-power-driven plasma flow
• Thomson scattering on the Large Plasma Device
• Two-dimensional Thomson scattering in high-repetition-rate laser-plasma experiments
• Laser-Driven, Ion-Scale Magnetospheres in Laboratory Plasmas. II. Particle-in-cell Simulations
• Strong collisionless coupling between an unmagnetized driver plasma and a magnetized background plasma
• Laboratory study of magnetic reconnection in lunar-relevant mini-magnetospheres
• Direct Measurement of Electron Heating in Electron-Only Reconnection in a Laboratory Mini-Magnetosphere
• Plasma Flow Generation and Particle Acceleration from Expanding Magnetic Bubbles