Shocklets, SLAMS, and field‐aligned ion beams in the terrestrial foreshock

  title={Shocklets, SLAMS, and field‐aligned ion beams in the terrestrial foreshock},
  author={Lynn Bruce Wilson and Andriy Koval and David Gary Sibeck and Adam Szabo and Cynthia A. Cattell and Justin C. Kasper and Bennett A. Maruca and Marc P. Pulupa and Chadi S. Salem and Mark Q. Wilber},
  journal={Journal of Geophysical Research: Space Physics},
  pages={957 - 966}
We present Wind spacecraft observations of ion distributions showing field‐aligned beams (FABs) and large‐amplitude magnetic fluctuations composed of a series of shocklets and short large‐amplitude magnetic structures (SLAMS). The FABs are found to have Tb ~ 80 − 850  eV, Vb/Vsw ~ 1. 3 − 2. 4, T⊥,b/T∥,b ~ 1–8, and nb/no ~ 0.2–11%. Saturation amplitudes for ion/ion resonant and non‐resonant instabilities are too small to explain the observed SLAMS amplitudes. We show two examples where groups of… 
Evidence for transient, local ion foreshocks caused by dayside magnetopause reconnection
Abstract. We present a scenario resulting in time-dependent behaviour of the bow shock and transient, local ion reflection under unchanging solar wind conditions. Dayside magnetopause reconnection
Evolution of High‐Speed Jets and Plasmoids Downstream of the Quasi‐Perpendicular Bow Shock
Plasma structures with enhanced dynamic pressure, density, or speed are often observed in Earth's magnetosheath. We present a statistical study of these structures, known as jets and fast plasmoids,
Ion distributions in the Earth's foreshock: Hybrid‐Vlasov simulation and THEMIS observations
We present the ion distribution functions in the ion foreshock upstream of the terrestrial bow shock obtained with Vlasiator, a new hybrid‐Vlasov simulation geared toward large‐scale simulations of
Observational Evidence of Magnetic Reconnection in the Terrestrial Bow Shock Transition Region
We report evidence of magnetic reconnection in the transition region of the Earth's bow shock when the angle between the shock normal and the immediate upstream magnetic field is 65°. An
A proton-cyclotron wave storm generated by unstable proton distribution functions in the solar wind
We use audification of 0.092 s cadence magnetometer data from the Wind spacecraft to identify waves with amplitudes >0.1 nT near the ion gyrofrequency (~0.1 Hz) with duration longer than 1 hr during
Formation of downstream high‐speed jets by a rippled nonstationary quasi‐parallel shock: 2‐D hybrid simulations
Experimental observations from space missions (including more recently Cluster and Time History of Events and Macroscale Interactions during Substorms data) have clearly revealed the existence of
Electron Energy Partition across Interplanetary Shocks. II. Statistics
A statistical analysis of 15,210 electron velocity distribution function (VDF) fits, observed within $\pm$2 hours of 52 interplanetary (IP) shocks by the $Wind$ spacecraft near 1 AU, is presented.
Characteristics of quasi‐monochromatic ULF waves in the Venusian foreshock
The statistical properties of ULF waves observed upstream of Venus foreshock are investigated. The study is restricted to waves which are observed well below the local proton cyclotron frequency.
Relativistic Electrons Produced by Foreshock Disturbances Observed Upstream of Earth's Bow Shock.
Observations of electrons energized by foreshock disturbances to energies up to at least ∼300  keV are reported, which could provide a new paradigm for electron injections and acceleration in collisionless plasmas.
Electron Resonant Interaction With Whistler Waves Around Foreshock Transients and the Bow Shock Behind the Terminator
Investigation of electron energization at (and around) the Earth's bow shock is critical to our understanding of space weather and astrophysical phenomena. The traditional adiabatic mechanisms for


Anomalous foreshock field-aligned beams observed by Cluster
We report occasional observations of two simul- taneously distinct ion foreshock components recorded by the Cluster spacecraft upstream of the Earth's bow shock. In most occurrences, the lower-energy
Full particle simulations of short large‐amplitude magnetic structures (SLAMS) in quasi‐parallel shocks
[1] Dynamics of SLAMS (short large-amplitude magnetic structures) is investigated by the use of one-dimensional, full particle electromagnetic simulations. As previous hybrid simulations and analysis
Scattering of field-aligned beam ions upstream of Earth's bow shock
Abstract. Field-aligned beams are known to originate from the quasi-perpendicular side of the Earth's bow shock, while the diffuse ion population consists of accelerated ions at the quasi-parallel
Cluster magnetic field observations at a quasi-parallel bow shock
Abstract. We present four-point Cluster magnetic field data from a quasi-parallel shock crossing which allows us to probe the three-dimensional structure of this type of shock for the first time. We
Simultaneous observations of field-aligned beams and gyrating ions in the terrestrial foreshock
[1] We examine an energetic (2–30 keV) upstream ion event presenting a clear doublepeak spectrum observed � 1 RE upstream from the bow shock. The lower-energy (E � 3.5 keV) peak is associated with an
Observations of short large-amplitude magnetic structures at a quasi-parallel shock
The authors have conducted a detailed analysis of a set of events termed short large-amplitude magnetic structures (SLAMS) observed at an encounter of the quasi-parallel bow shock by the AMPTE UKS
Observations of electromagnetic whistler precursors at supercritical interplanetary shocks
We present observations of electromagnetic precursor waves, identified as whistler mode waves, at supercritical interplanetary shocks using the Wind search coil magnetometer. The precursors propagate
Multi‐point electric field measurements of Short Large‐Amplitude Magnetic Structures (SLAMS) at the Earth's quasi‐parallel bow shock
We present the first direct measurements of the electric field and plasma density with high resolution in Short Large‐Amplitude Magnetic Structures (SLAMS) at a quasi‐parallel shock crossing. Cluster
Nonthermal ions and associated magnetic field behavior at a quasi-parallel earth's bow shock
Ion and magnetic field measurements at Earth's bow shock from the AMPTE-UKS and -IRM spacecraft, are examined in high time resolution during a 45-min interval when the field remained closely aligned
Statistical analysis of short large‐amplitude magnetic field structures in the vicinity of the quasi‐parallel bow shock
Short large-amplitude magnetic field structures (SLAMS) appear in the vicinity of the quasi-parallel region of the Earth's bow shock. Using the magnetic field and plasma data of the AMPTE/IRM and UKS