Solar wind discontinuity transformation at the bow shock
arXiv:2106.06414 · doi:10.3847/1538-4357/abf6c7
Abstract
Solar wind plasma at the Earth's orbit carries transient magnetic field structures including discontinuities. Their interaction with the Earth's bow shock can significantly alter discontinuity configuration and stability. We investigate such an interaction for the most widespread type of solar wind discontinuities - rotational discontinuities (RDs). We use a set of in situ multispacecraft observations and perform kinetic hybrid simulations. We focus on the RD current density amplification that may lead to magnetic reconnection. We show that the amplification can be as high as two orders of magnitude and is mainly governed by three processes: the transverse magnetic field compression, global thinning of RD, and interaction of RD with low-frequency electromagnetic waves in the magnetosheath, downstream of the bow shock. The first factor is found to substantially exceed simple hydrodynamic predictions in most observed cases, the second effect has a rather moderate impact, while the third causes strong oscillations of the current density. We show that the presence of accelerated particles in the bow shock precursor highly boosts the current density amplification, making the postshock magnetic reconnection more probable. The pool of accelerated particles strongly affects the interaction of RDs with the Earth's bow shock, as it is demonstrated by observational data analysis and hybrid code simulations. Thus, shocks should be distinguished not by the inclination angle, but rather by the presence of foreshocks populated with shock reflected particles. Plasma processes in the RD-shock interaction affect magnetic structures and turbulence in the Earth's magnetosphere and may have implications for the processes in astrophysics.
References in corpus (23)
- Diamagnetic Suppression of Component Magnetic Reconnection at the Magnetopause
- Acceleration of Particles at the Termination Shock of a Relativistic Striped Wind
- Intermittent Dissipation and Local Heating in the Solar Wind
- Pulsar Wind Nebulae as Cosmic Pevatrons: A Current Sheet's Tale
- Parker Solar Probe In-Situ Observations of Magnetic Reconnection Exhausts During Encounter 1
- Pulsar wind nebulae with bow shocks: non-thermal radiation and cosmic ray leptons
- Geminga's puzzling pulsar wind nebula
- The Complex Structure of Magnetic Field Discontinuities in the Turbulent Solar Wind
- Magnetic field amplification in nonlinear diffusive shock acceleration including resonant and non-resonant cosmic-ray driven instabilities
- Diffusive Shock Re-Acceleration
- Localized magnetic field structures and their boundaries in the near-Sun solar wind from Parker Solar Probe measurements
- Fluid Models for Kinetic Effects on Coherent Nonlinear Alfven Waves. II. Numerical Solutions
- Non-linear model of particle acceleration at colliding shock flows
- Shocks and non-thermal particles in clusters of galaxies
- Dissipative Dynamics of Collisionless Nonlinear Alfven Wave Trains
- GeV-TeV Cosmic Ray Leptons in the Solar System from the Bow Shock Wind Nebula of the Nearest Millisecond Pulsar J0437-4715
- A nonlinear Monte Carlo model of super-diffusive shock acceleration with magnetic field amplification
- Kinetic models of tangential discontinuities in the solar wind
- Formation of foreshock transients and associated secondary shocks
- Ion-scale current structures in Short Large-Amplitude Magnetic Structures
- A family of Vlasov-Maxwell equilibrium distribution functions describing a transition from the Harris sheet to the force-free Harris sheet
- Maximus: a Hybrid Particle-in-Cell Code for Microscopic Modeling of Collisionless Plasmas
- Simulation of collisionless shocks in plasmas with high metallicity