Penetration of magnetosheath plasma into dayside magnetosphere: 1. Density, velocity, and rotation

Lyatsky, W.; Pollock, C. J.; Goldstein, M. L.; Lyatskaya, Sonya; Avanov, L. A.

doi:10.1002/2015ja022119

Cited by 8 publications

(14 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This definition admits different ways to implement this mechanism in the frames of the model of impulsive penetration, including the MHD, kinetic approach, or other models. This manuscript is a continuation of our previous study [ Lyatsky et al ., ] (part 1), where we investigated the plasma density, velocity, and rotation of these plasma filaments; in this study we investigate the magnetic field in these filaments.…”

Section: Introductionmentioning

confidence: 99%

Penetration of magnetosheath plasma into dayside magnetosphere: 2. Magnetic field in plasma filaments

et al. 2016

Self Cite

View full text Add to dashboard Cite

In this paper, we examined plasma structures (filaments), observed in the dayside magnetosphere but containing magnetosheath plasma. These filaments show the stable antisunward motion (while the ambient magnetospheric plasma moved in the opposite direction) and the existence of a strip of magnetospheric plasma, separating these filaments from the magnetosheath. These results, however, contradict both theoretical studies and simulations by Schindler (1979), Ma et al. (1991), Dai and Woodward (1994, 1998), and other researchers, who reported that the motion of such filaments through the magnetosphere is possible only when their magnetic field is directed very close to the ambient magnetic field, which is not the situation that is observed. In this study, we show that this seeming contradiction may be related to different events as the theoretical studies and simulations are related to the case when the filament magnetic field is about aligned with filament orientation, whereas the observations show that the magnetic field in these filaments may be rotating. In this case, the rotating magnetic field, changing incessantly its direction, drastically affects the penetration of plasma filaments into the magnetosphere. In this case, the filaments with rotating magnetic field, even if in each moment it is significantly inclined to the ambient magnetic field, may propagate through the magnetosphere, if their average (for the rotation period) magnetic field is aligned with the ambient magnetic field. This shows that neglecting the rotation of magnetic field in these filaments may lead to wrong results.

show abstract

Section: Introductionmentioning

confidence: 99%

Penetration of magnetosheath plasma into dayside magnetosphere: 2. Magnetic field in plasma filaments

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Magnetosheath irregularities are investigated theoretically and with in-situ experimental data. They are described in the literature under various names, like magnetosheath plasma blobs or plasmoids (Lemaire, 1985;Echim and Lemaire, 2000;Karlsson et al, 2012;Karlsson et al, 2015), magnetosheath transient flux enhancements (Nemecek et al, 1998), plasma clouds or plasma transfer events (Lundin et al, 2003), magnetosheath pressure pulses (Archer et al, 2012), plasma jets Savin et al, 2008;Hietala et al, 2009;Amata et al, 2011), plasma filaments (Lyatsky et al, 2016a;Lyatsky et al, 2016b) (see also Table 1 in Plaschke et al, 2018). Some authors use the term "jet" for magnetosheath structures characterized by an excess of dynamic pressure, p dyn = ρV 2 (e.g., Plaschke et al, 2013), while the term "plasmoid" is used for magnetosheath irregularities with an excess of density, ρ (e.g., Karlsson et al, 2012), or momentum, p = ρV (Lemaire, 1977;Lemaire, 1985).…”

Section: Methodsmentioning

confidence: 99%

“…The conditions for magnetopause traversal are investigated with 3D electromagnetic Particle-in-Cell numerical simulations (Voitcu and Echim, 2016;Voitcu and Echim, 2017;Voitcu and Echim, 2018). Magnetospheric observations of fully penetrated magnetosheath plasma elements are reported by studies based on data from magnetospheric missions like Prognoz-7 (Lundin and Aparicio, 1982;Lundin and Dubinin, 1984;Lundin, 1988), INTERBALL (Vaisberg et al, 1998), Cluster (Lundin et al, 2003;Gunell et al, 2012;Lyatsky et al, 2016a;Lyatsky et al, 2016b), THEMIS (Dmitriev and Suvorova, 2015). Lundin et al (2003) report Cluster observations of 134 magnetosheath jets detected, between January-March 2001, inside the magnetosphere, at high latitudes (they call these structures plasma transfer events-PTE).…”

Section: Magnetospheric and Ionospheric Effects Of Magnetosheath Jetsmentioning

confidence: 99%

On the phenomenology of magnetosheath jets with insight from theory, modelling, numerical simulations and observations by Cluster spacecraft

Echim

Voiculescu²,

Munteanu³

et al. 2023

Front. Astron. Space Sci.

View full text Add to dashboard Cite

Introduction: During recent years magnetosheath plasma structures called “jets” are identified in spacecraft data as localized regions in the magnetosheath where the dynamic pressure is enhanced compared to the background. Although the nomenclature and detection algorithms vary from author to author, magnetosheath jets are part of a larger class of phenomena which can be globally called magnetosheath irregularities. In this review we focus on elements of jets phenomenology less discussed in the literature, though sustained by theoretical models for solar wind magnetosphere interaction, numerical studies based on Vlasov equilibrium models or kinetic numerical simulations.Methods: The self-consistency of magnetosheath jets and the preservation of their physical identity (shape and physical properties), implicitly assumed in many recent experimental studies, is discussed in modelling and simulations studies and results as a consequence of kinetic processes at the edges of the jets. These studies provide evidence for the fundamental role played by a polarization electric field sustaining the forward motion of the jet with respect to the background plasma. Another natural consequence is the backward motion of surrounding magnetosheath plasma at the edges of jets. The conservation of magnetic moment of ions leads to a decrease of jets forward speed when it moves into increasing magnetic field. Our review is complemented by an analysis of magnetosheath data recorded by Cluster in 2007 and 2008. We applied an algorithm to detect jets based on searching localized enhancements of the dynamic pressure.Results: This algorithm identifies a number of 960 magnetosheath jets (354 events in 2007 versus 606 events in 2008). A statistical analysis of jet plasma properties reveals an asymmetric distribution of the number of jets as well as a dawn-dusk asymmetry of jets temperature and density. The perturbative effects of jets on the background magnetosheath density/temperature are stronger in the dusk/dawn flank. We also found evidence for deceleration and perpendicular heating of jets with decreasing distance to the Earth. The braking of jets is correlated with the variation of the magnetic field intensity: the stronger the magnetic field gradient, the more efficient is the jet breaking.

show abstract

“…Some of the penetrating plasmoids were intersected in situ by spacecraft deep inside the magnetosphere (e.g. Lundin and Aparicio, 1982;Lundin, 1991, 1992;Yamauchi et al, 1993;Lu et al, 2004;Gunell et al, 2012;Shi et al, 2013;Lyatsky et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

“…The transport of plasma jets, clouds and blobs across various magnetic field configurations has been investigated with magnetohydrodynamic (MHD) (e.g. Ma et al, 1991;Dai and Woodward, 1994, 1995, 1998Huba, 1996), hybrid (e.g. Savoini et al, 1994;Palmroth et al, 2018) and kinetic (e.g.…”

Section: Introductionmentioning

confidence: 99%

Crescent-shaped electron velocity distribution functions formed at the edges of plasma jets interacting with a tangential discontinuity

Voitcu

Echim

2018

Ann. Geophys.

View full text Add to dashboard Cite

In this paper we discuss numerical simulations that illustrate a physical mechanism leading to the formation of crescent-shaped electron velocity distribution functions at the edges of a high-speed plasma jet impacting on a thin, steep and impenetrable tangential discontinuity with no magnetic shear. We use three-dimensional particle-in-cell simulations to compute the velocity distribution function of electrons in different areas of the plasma jet and at different phases of the interaction with the discontinuity. The simulation set-up corresponds to an idealized, yet relevant, magnetic configuration likely to be observed at the frontside magnetopause under the northward interplanetary magnetic field. The combined effect of the gradient-B drift and the remote sensing of large Larmor radius electrons leads to the formation of crescent-shaped electron velocity distribution functions. We provide examples of such distributions "measured" by a virtual satellite launched into the simulation domain.

show abstract

Penetration of magnetosheath plasma into dayside magnetosphere: 1. Density, velocity, and rotation

Cited by 8 publications

References 32 publications

Penetration of magnetosheath plasma into dayside magnetosphere: 2. Magnetic field in plasma filaments

Penetration of magnetosheath plasma into dayside magnetosphere: 2. Magnetic field in plasma filaments

On the phenomenology of magnetosheath jets with insight from theory, modelling, numerical simulations and observations by Cluster spacecraft

Crescent-shaped electron velocity distribution functions formed at the edges of plasma jets interacting with a tangential discontinuity

Contact Info

Product

Resources

About