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Sun-Heliosphere Observation-based Ionization Rates Model
McComas, D. J.; Bzowski, M.; Tokumaru, M. +1 more
The solar wind (SW) and the extreme ultraviolet (EUV) radiation modulate fluxes of interstellar and heliospheric particles inside the heliosphere both in time and in space. Understanding this modulation is necessary to correctly interpret measurements of particles of interstellar origin inside the heliosphere. We present a revision of heliospheric…
Prediction of the In Situ Coronal Mass Ejection Rate for Solar Cycle 25: Implications for Parker Solar Probe In Situ Observations
Lugaz, Noé; Möstl, Christian; McIntosh, Scott W. +7 more
The Parker Solar Probe (PSP) and Solar Orbiter missions are designed to make groundbreaking observations of the Sun and interplanetary space within this decade. We show that a particularly interesting in situ observation of an interplanetary coronal mass ejection (ICME) by PSP may arise during close solar flybys (<0.1 au). During these times, t…
Effects of Radial Distances on Small-scale Magnetic Flux Ropes in the Solar Wind
Hu, Qiang; Chen, Yu
Small-scale magnetic flux ropes (SFRs) in the solar wind have been studied for decades. Statistical analysis utilizing various in situ spacecraft measurements is the main observational approach to investigating the generation and evolution of these small-scale structures. Based on the Grad-Shafranov reconstruction technique, we use the automated d…
Numerical Modeling of Suprathermal Electron Transport in the Solar Wind: Effects of Whistler Turbulence
Zank, Gary P.; Tang, Bofeng; Kolobov, Vladimir I.
The solar wind electron velocity distribution function deviates significantly from an equilibrium Maxwellian distribution and is composed of a Maxwellian core, a suprathermal halo, a field-aligned component strahl, and a higher-energy superhalo. Wave-particle interactions associated with whistler wave turbulence are introduced into the kinetic tra…
On the Production of He+ of Solar Origin in the Solar Wind
Landi, Enrico; Rivera, Yeimy J.; Lepri, Susan T. +1 more
Solar wind measurements in the heliosphere predominantly comprise protons, alphas, and minor elements in a highly ionized state. The majority of low-charge states, such as He+, measured in situ are often attributed to pick-up ions of nonsolar origin. However, through inspection of the velocity distribution functions of near-Earth measur…
Magnetohydrodynamic Turbulent Evolution of a Magnetic Cloud in the Outer Heliosphere
Telloni, Daniele; Zank, Gary P.; Adhikari, Laxman +8 more
This Letter exploits joint observations of the same interplanetary coronal mass ejection by widely separated spacecraft to study, for the first time, the turbulent evolution of the magnetohydrodynamic (MHD) properties of the embedded magnetic cloud, during its propagation throughout interplanetary space. Specifically, the event was observed by Win…
The Space Environment and Atmospheric Joule Heating of the Habitable Zone Exoplanet TOI 700 d
Drake, Jeremy J.; Garraffo, C.; Alvarado-Gómez, J. D. +4 more
We investigate the space environment conditions near the Earth-size planet TOI 700 d using a set of numerical models for the stellar corona and wind, the planetary magnetosphere, and the planetary ionosphere. We drive our simulations using a scaled-down stellar input and a scaled-up solar input in order to obtain two independent solutions. We find…
Distance to the Energetic Neutral Hydrogen Source from the Heliotail
McComas, D. J.; Dayeh, M. A.; Sokół, J. M. +1 more
The interaction of the solar wind (SW) with the partially ionized interstellar medium forms the heliosphere. As the supersonic SW flows away from the Sun and incorporates pickup ions (PUIs), they are slowed, compressed, and heated at a termination shock, creating an energetic ion population in the inner heliosheath. The neutralization of PUIs in t…
Whether Small Flux Ropes and Magnetic Clouds Have the Same Origin: A Statistical Study of Small Flux Ropes in Different Types of Solar Wind
Wang, Yuming; Shen, Chenglong; Hu, Qiang +2 more
According to the duration and size, magnetic flux ropes can be divided into large-scale flux ropes, namely, magnetic clouds, and small-scale flux ropes (SFRs). Whether SFRs have the same origin as magnetic clouds has been a hot topic for a long time. Based on the SFR database developed by Hu et al. and Chen et al., this paper analyzes the properti…
Simulation of the Interplanetary Bz Using a Data-driven Heliospheric Solar Wind Model
Feng, Xueshang; Zuo, Pingbing; Wei, Fengsi +1 more
Aimed to be ready for the transition from research to operation, we have developed a solar wind model by coupling a data-driven empirical coronal model with a magnetohydrodynamics heliospheric model. We performed a data-driven simulation of the solar wind for a two-year period during the declining and minimum phases of solar cycle 23. Comparisons …