Marginal stability of whistler-mode waves in plasma with multiple electron populations

Frantsuzov, V. A.; Artemyev, А. V.; Shustov, Pavel; Zhang, Xiaojia

doi:10.1063/5.0085953

Cited by 6 publications

(5 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The median value of Δf/〈f〉 is ∼0.2 in the core and in the compressional boundaries. A large portion of the observed waves are quite narrow-banded, which suggests a narrow resonant energy range of electrons responsible for wave generation, i.e., the anisotropic electron population is bounded below and above in energy by isotropic cold and hot electrons, respectively (e.g., Fu et al 2014;Page et al 2021;Frantsuzov et al 2022).…”

Section: Statistical Resultsmentioning

confidence: 99%

Intense Whistler-mode Waves at Foreshock Transients: Characteristics and Regimes of Wave−Particle Resonant Interaction

Shi¹,

Liu²,

Artemyev

et al. 2023

ApJ

Self Cite

View full text Add to dashboard Cite

Thermalization and heating of plasma flows at shocks result in unstable charged-particle distributions that generate a wide range of electromagnetic waves. These waves, in turn, can further accelerate and scatter energetic particles. Thus, the properties of the waves and their implication for wave−particle interactions are critically important for modeling energetic particle dynamics in shock environments. Whistler-mode waves, excited by the electron heat flux or a temperature anisotropy, arise naturally near shocks and foreshock transients. As a result, they can often interact with suprathermal electrons. The low background magnetic field typical at the core of such transients and the large wave amplitudes may cause such interactions to enter the nonlinear regime. In this study, we present a statistical characterization of whistler-mode waves at foreshock transients around Earth’s bow shock, as they are observed under a wide range of upstream conditions. We find that a significant portion of them are sufficiently intense and coherent (narrowband) to warrant nonlinear treatment. Copious observations of background magnetic field gradients and intense whistler wave amplitudes suggest that phase trapping, a very effective mechanism for electron acceleration in inhomogeneous plasmas, may be the cause. We discuss the implications of our findings for electron acceleration in planetary and astrophysical shock environments.

show abstract

Section: Statistical Resultsmentioning

confidence: 99%

Intense Whistler-mode Waves at Foreshock Transients: Characteristics and Regimes of Wave−Particle Resonant Interaction

Shi¹,

Liu²,

Artemyev

et al. 2023

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…A more complicated (and probably more realistic) system should include a set of electron populations with different anisotropies, densities, and temperatures (see, e.g., Vasko et al 2019, for a discussion of a multicomponent electron population in the solar wind). The interplay of such populations may significantly affect the wave spectrum (e.g., Fu et al 2014;Li et al 2016;Sauer et al 2020;Vasko et al 2020;Frantsuzov et al 2022) and alter the evolution of the electron distribution. Therefore, to obtain general results about the efficiency of the magnetic pumping, we use a simplified system with a single hot (resonating with waves) electron component, whereas more realistic multicomponent systems should be considered for specific solar wind (or magnetic foreshock) events.…”

Section: Theoretical Modelmentioning

confidence: 99%

Electron Heating by Magnetic Pumping and Whistler-mode Waves

Frantsuzov,

Artemyev,

Shi

et al. 2024

ApJ

Self Cite

View full text Add to dashboard Cite

The investigation of mechanisms responsible for the heating of cold solar wind electrons around the Earth’s bow shock is an important problem in heliospheric plasma physics because such heating is vitally required to run the shock drift acceleration at the bow shock. The prospective mechanism for electron heating is magnetic pumping, which considers electron adiabatic (compressional) heating by ultralow-frequency waves and simultaneous scattering by high-frequency fluctuations. Existing models of magnetic pumping have operated with external sources of such fluctuations. In this study, we generalize these models by introducing the self-consistent electron scattering by whistler-mode waves generated due to the anisotropic electron heating process. We consider an electron population captured within a magnetic trap created by ultralow-frequency waves. Periodical adiabatic heating and cooling of this population drives the generation of whistler-mode waves scattering electrons in the pitch-angle space. The combination of adiabatic heating and whistler-driven scattering provides electron acceleration and the formation of a suprathermal electron population that can further participate in the shock drift acceleration.

show abstract

“…(2014); X. Zhang, Angelopoulos, Artemyev, and Zhang (2021); Frantsuzov et al. (2022)). The gray region in Figure 3 marks positions of the model magnetopause (Shue et al., 1997) for all events, and for each event, we visually inspect the plasma and magnetic field measurements to confirm that whistler‐mode and ECH waves are observed within the magnetosphere.…”

Section: Spacecraft Instruments and Data Setmentioning

confidence: 99%

Statistical Analysis of Concurrent Electron Cyclotron Harmonic and Whistler Waves Driven by ULF Waves

Waheed¹,

Bashir

Artemyev

et al. 2023

JGR Space Physics

Self Cite

View full text Add to dashboard Cite

Plasma sheet electron precipitation to the diffuse aurora is one of the primary mechanisms of magnetospheric energy transport to the Earth’s atmosphere. Such precipitation is provided by electron resonant interactions with electron cyclotron harmonics (ECH) and whistler‐mode waves in the near‐Earth plasma sheet. ECH and whistler‐mode wave generation is traditionally attributed to two main sources of free energy: the loss‐cone anisotropy and the temperature anisotropy due to transverse electron heating during earthward convection or plasma sheet injections. This paper considers a third free energy source for ECH and whistler‐mode wave generation—the electron distribution modulation by compressional ultra‐low‐frequency (ULF) waves. We conduct statistics of ECH and whistler‐mode wave bursts associated with ULF waves and show that: (a) such bursts are mostly observed on the dawn flank, (b) 83% of events show a correlation between ECH and whistler‐mode bursts, and the rest 17% show anti‐correlation, (c) ECH and whistler‐mode wave intensities are comparable with those observed around the night‐side injection region. We investigate the main characteristics of ECH and whistler‐mode waves modulated by ULF waves and provide an empirical model for these characteristics. This model can be directly incorporated into simulation frameworks, so as to include these ULF‐modulated wave bursts in simulations of the magnetosphere‐ionosphere coupling and radiation belt dynamics.

show abstract

Marginal stability of whistler-mode waves in plasma with multiple electron populations

Cited by 6 publications

References 69 publications

Intense Whistler-mode Waves at Foreshock Transients: Characteristics and Regimes of Wave−Particle Resonant Interaction

Intense Whistler-mode Waves at Foreshock Transients: Characteristics and Regimes of Wave−Particle Resonant Interaction

Electron Heating by Magnetic Pumping and Whistler-mode Waves

Statistical Analysis of Concurrent Electron Cyclotron Harmonic and Whistler Waves Driven by ULF Waves

Contact Info

Product

Resources

About