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The Radial Variation of the Solar Wind Turbulence Spectra near the Kinetic Break Scale from Parker Solar Probe Measurements
Bale, S. D.; Kontar, E. P.; Engelbrecht, N. E. +7 more
In this study we examine the radial dependence of the inertial and dissipation range indices, as well as the spectral break separating the inertial and dissipation range in power density spectra of interplanetary magnetic field fluctuations using Parker Solar Probe data from the fifth solar encounter between ~0.1 and ~0.7 au. The derived break wav…
Modeling a Coronal Mass Ejection from an Extended Filament Channel. II. Interplanetary Propagation to 1 au
Scolini, Camilla; Lynch, Benjamin J.; Palmerio, Erika +5 more
We present observations and modeling results of the propagation and impact at Earth of a high-latitude, extended filament channel eruption that commenced on 2015 July 9. The coronal mass ejection (CME) that resulted from the filament eruption was associated with a moderate disturbance at Earth. This event could be classified as a so-called "proble…
Estimates of Proton and Electron Heating Rates Extended to the Near-Sun Environment
McComas, D. J.; Bale, S. D.; Cranmer, S. R. +11 more
A central problem of space plasma physics is how protons and electrons are heated in a turbulent, magnetized plasma. The differential heating of charged species due to dissipation of turbulent fluctuations plays a key role in solar wind evolution. Measurements from previous heliophysics missions have provided estimates of proton and electron heati…
Unfolding Drift Effects for Cosmic Rays over the Period of the Sun's Magnetic Field Reversal
Luo, Xi; Potgieter, M. S.; Aslam, O. P. M. +2 more
A well-established, comprehensive 3D numerical modulation model is applied to simulate galactic protons, electrons, and positrons from 2011 May to 2015 May, including the solar magnetic polarity reversal of Solar Cycle 24. The objective is to evaluate how simulations compare with corresponding Alpha Magnetic Spectrometer observations for 1.0-3.0 G…
The Polytropic Behavior of Solar Wind Protons as Observed by the Ulysses Spacecraft during Solar Minimum
Livadiotis, George; Nicolaou, Georgios; McComas, David J.
We analyze proton bulk parameters derived from Ulysses observations and investigate the polytropic behavior of solar wind protons over a wide range of heliocentric distances and latitudes. The large-scale variations of the proton density and temperature over heliocentric distance indicate that plasma protons are governed by subadiabatic processes …
Formulating Mass-loss Rates for Sun-like Stars: A Hybrid Model Approach
Toriumi, Shin; Cranmer, Steven R.; Shoda, Munehito
We observe an enhanced stellar wind mass-loss rate from low-mass stars exhibiting higher X-ray flux. This trend, however, does not align with the Sun, where no evident correlation between X-ray flux and mass-loss rate is present. To reconcile these observations, we propose a hybrid model for the stellar wind from solar-type stars, incorporating bo…
A Three-dimensional Model for the Evolution of Magnetohydrodynamic Turbulence in the Outer Heliosphere
Oughton, Sean; Fichtner, Horst; Kleimann, Jens +1 more
We present a time-dependent, three-dimensional single-fluid model for the transport of magnetohydrodynamic (MHD) turbulence that is self-consistently evolving with a dynamic large-scale solar wind in the outer heliosphere. The emphasis is on the region beyond the termination shock, where the solar wind expands subsonically, as well as sub-Alfvénic…
Modulation of Cosmic-Ray Antiprotons in the Heliosphere: Simulations for a Solar Cycle
Luo, Xi; Potgieter, M. S.; Aslam, O. P. M. +1 more
The precision measurements of galactic cosmic-ray protons from the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics and the Alpha Magnetic Spectrometer are reproduced using a well-established three-dimensional numerical model for the period 2006 July-2019 November. The resulting modulation parameters are applied to simulate …
Connection between Polytropic Index and Heating
McComas, D. J.; Livadiotis, G.
The paper derives the one-to-one connecting relationships between plasma heating and its polytropic index, and addresses the consequences through the transport equation of temperature. Thermodynamic polytropic processes are classified in accordance to their polytropic index, the exponent of the power-law relationship of thermal pressure expressed …
Influence of Intermittency on the Energy Transfer Rate of Solar Wind Turbulence
Wang, Xin; Yuan, Zhigang; Huang, Shiyong +2 more
The intermittency in the solar wind turbulence manifests itself in the anisotropic scaling due to the anisotropic spectral index and the intermittent level based on the extended P model. However, the influence of intermittency on the energy transfer rate remains unclear. Here we apply the partial variance of increments method to identify the inter…