Search Publications
Theory of Cosmic Ray Transport in the Heliosphere
Rankin, J. S.; Potgieter, M. S.; Ruffolo, D. +6 more
Modelling the transport of cosmic rays (CRs) in the heliosphere represents a global challenge in the field of heliophysics, in that such a study, if it were to be performed from first principles, requires the careful modelling of both large scale heliospheric plasma quantities (such as the global structure of the heliosphere, or the heliospheric m…
The Structure of the Large-Scale Heliosphere as Seen by Current Models
Heerikhuisen, Jacob; Fraternale, Federico; Pogorelov, Nikolai +6 more
This review summarizes the current state of research aiming at a description of the global heliosphere using both analytical and numerical modeling efforts, particularly in view of the overall plasma/neutral flow and magnetic field structure, and its relation to energetic neutral atoms. Being part of a larger volume on current heliospheric researc…
Anomalous Cosmic Rays and Heliospheric Energetic Particles
Fichtner, H.; Leske, R. A.; Hill, M. E. +7 more
We present a review of Anomalous Cosmic Rays (ACRs), including the history of their discovery and recent insights into their acceleration and transport in the heliosphere. We focus on a few selected topics including a discussion of mechanisms of their acceleration, escape from the heliosphere, their effects on the dynamics of the heliosheath, tran…
Recent Developments in Particle Acceleration at Shocks: Theory and Observations
Giacalone, Joe; Perri, Silvia; Fichtner, Horst +2 more
Energetic particles represent an important component of the plasma in the heliosphere. They range from particles accelerated at impulsive events in the solar corona and at large scale structures in the interplanetary medium, to anomalous cosmic rays accelerated at the boundaries of the heliosphere. In-situ satellite observations, numerical simulat…
Turbulence in the Outer Heliosphere
Zank, Gary P.; Adhikari, Laxman; Zhao, Lingling +9 more
The solar wind (SW) and local interstellar medium (LISM) are turbulent media. Their interaction is governed by complex physical processes and creates heliospheric regions with significantly different properties in terms of particle populations, bulk flow and turbulence. Our knowledge of the solar wind turbulence nature and dynamics mostly relies o…
In Situ Observations of Interstellar Pickup Ions from 1 au to the Outer Heliosphere
McComas, D. J.; Möbius, E.; Pogorelov, N. V. +5 more
Interstellar pickup ions are an ubiquitous and thermodynamically important component of the solar wind plasma in the heliosphere. These PUIs are born from the ionization of the interstellar neutral gas, consisting of hydrogen, helium, and trace amounts of heavier elements, in the solar wind as the heliosphere moves through the local interstellar m…
Galactic Cosmic Rays Throughout the Heliosphere and in the Very Local Interstellar Medium
Heber, Bernd; Zhang, Ming; Potgieter, Marius S. +7 more
We review recent observations and modeling developments on the subject of galactic cosmic rays through the heliosphere and in the Very Local Interstellar Medium, emphasizing knowledge that has accumulated over the past decade. We begin by highlighting key measurements of cosmic-ray spectra by Voyager, PAMELA, and AMS and discuss advances in global…
Inhomogeneity in the Local ISM and Its Relation to the Heliosphere
Redfield, Seth; Linsky, Jeffrey; Ryder, Diana +1 more
This paper reviews past research and new studies underway of the local interstellar environment and its changing influence on the heliosphere. The size, shape, and physical properties of the heliosphere outside of the heliopause are determined by the surrounding environment - now the outer region of the Local Interstellar Cloud (LIC). The temperat…
The Heliosphere and Local Interstellar Medium from Neutral Atom Observations at Energies Below 10 keV
Schwadron, Nathan A.; Izmodenov, Vladislav V.; Kucharek, Harald +8 more
As the heliosphere moves through the surrounding interstellar medium, a fraction of the interstellar neutral helium, hydrogen, and heavier species crossing the heliopause make it to the inner heliosphere as neutral atoms with energies ranging from few eV to several hundred eV. In addition, energetic neutral hydrogen atoms originating from solar wi…
Interstellar Neutrals, Pickup Ions, and Energetic Neutral Atoms Throughout the Heliosphere: Present Theory and Modeling Overview
Zank, Gary P.; Zhang, Ming; Mostafavi, Parisa +11 more
Interstellar neutrals (ISNs), pick-up ions (PUIs), and energetic neutral atoms (ENAs) are fundamental constituents of the heliosphere and its interaction with the neighboring interstellar medium. Here, we focus on selected aspects of present-day theory and modeling of these particles. In the last decades, progress in the understanding of the role …