Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Physics
Neutral Atom Imaging Of The Magnetospheric Cusps, S. M. Petrinec, M. A. Dayeh, H. O. Funsten, S. A. Fuselier, David F. Heirtzler, P. Janzen, Harald A. Kucharek, D. J. Mccomas, Eberhard Moebius, T. E. Moore, D. B. Reisenfeld, Nathan A. Schwadron, K. J. Trattner, P. Wurz
Neutral Atom Imaging Of The Magnetospheric Cusps, S. M. Petrinec, M. A. Dayeh, H. O. Funsten, S. A. Fuselier, David F. Heirtzler, P. Janzen, Harald A. Kucharek, D. J. Mccomas, Eberhard Moebius, T. E. Moore, D. B. Reisenfeld, Nathan A. Schwadron, K. J. Trattner, P. Wurz
Physics & Astronomy
The magnetospheric cusps separate closed dayside magnetospheric field lines from open field lines of the magnetotail mantle and lobes. All magnetospheric field lines that map to the magnetopause also pass through the cusp regions. Thus whenever magnetic reconnection occurs at the magnetopause, magnetosheath plasma can enter one or both of the cusp regions and charge exchange with the geocorona. The resulting energetic neutral atoms (ENAs) resulting from this charge exchange process propagate away from the cusps and are observed remotely by the Interstellar Boundary Explorer (IBEX). The asymmetry of the ENA intensities between the northern and southern cusps are strongly …
The Radial Evolution Of Solar Wind Speeds, S. L. Mcgregor, W. J. Hughes, C. N. Arge, D. Odstrcil, Nathan A. Schwadron
The Radial Evolution Of Solar Wind Speeds, S. L. Mcgregor, W. J. Hughes, C. N. Arge, D. Odstrcil, Nathan A. Schwadron
Physics & Astronomy
The WSA-ENLIL model predicts significant evolution of the solar wind speed. Along a flux tube the solar wind speed at 1.0 AU and beyond is found to be significantly altered from the solar wind speed in the outer corona at 0.1 AU, with most of the change occurring within a few tenths of an AU from the Sun. The evolution of the solar wind speed is most pronounced during solar minimum for solar wind with observed speeds at 1.0 AU between 400 and 500 km/s, while the fastest and slowest solar wind experiences little acceleration or deceleration. Solar wind ionic …
First Ibex Observations Of The Terrestrial Plasma Sheet And A Possible Disconnection Event, D. J. Mccomas, M. A. Dayeh, H. O. Funsten, S. A. Fuselier, J. Goldstein, J. M. Jahn, P. Janzen, D. G. Mitchell, S. M. Petrinec, D. B. Reisenfeld, Nathan A. Schwadron
First Ibex Observations Of The Terrestrial Plasma Sheet And A Possible Disconnection Event, D. J. Mccomas, M. A. Dayeh, H. O. Funsten, S. A. Fuselier, J. Goldstein, J. M. Jahn, P. Janzen, D. G. Mitchell, S. M. Petrinec, D. B. Reisenfeld, Nathan A. Schwadron
Physics & Astronomy
The Interstellar Boundary Explorer (IBEX) mission has recently provided the first all-sky maps of energetic neutral atoms (ENAs) emitted from the edge of the heliosphere as well as the first observations of ENAs from the Moon and from the magnetosheath stagnation region at the nose of the magnetosphere. This study provides the first IBEX images of the ENA emissions from the nightside magnetosphere and plasma sheet. We show images from two IBEX orbits: one that displays typical plasma sheet emissions, which correlate reasonably well with a model magnetic field, and a second that shows a significant intensification that may indicate …
Evolving Outer Heliosphere: Large-Scale Stability And Time Variations Observed By The Interstellar Boundary Explorer, D. J. Mccomas, M. Bzowski, P. Frisch, G. B. Crew, M. A. Dayeh, R. Demajistre, H. O. Funsten, S. A. Fuselier, M. Gruntman, P. Janzen, M. A. Kubiak, G Livadiotis, Eberhard Moebius, D. B. Reisenfeld, Nathan A. Schwadron
Evolving Outer Heliosphere: Large-Scale Stability And Time Variations Observed By The Interstellar Boundary Explorer, D. J. Mccomas, M. Bzowski, P. Frisch, G. B. Crew, M. A. Dayeh, R. Demajistre, H. O. Funsten, S. A. Fuselier, M. Gruntman, P. Janzen, M. A. Kubiak, G Livadiotis, Eberhard Moebius, D. B. Reisenfeld, Nathan A. Schwadron
Physics & Astronomy
The first all-sky maps of Energetic Neutral Atoms (ENAs) from the Interstellar Boundary Explorer (IBEX) exhibited smoothly varying, globally distributed flux and a narrow "ribbon" of enhanced ENA emissions. In this study we compare the second set of sky maps to the first in order to assess the possibility of temporal changes over the 6 months between views of each portion of the sky. While the large-scale structure is generally stable between the two sets of maps, there are some remarkable changes that show that the heliosphere is also evolving over this short timescale. In particular, we find that (1) …
Energy Dissipation And Ion Heating At The Heliospheric Termination Shock, P. Wu, D. Winske, S. P. Gary, Nathan A. Schwadron, Martin A. Lee
Energy Dissipation And Ion Heating At The Heliospheric Termination Shock, P. Wu, D. Winske, S. P. Gary, Nathan A. Schwadron, Martin A. Lee
Physics & Astronomy
The Los Alamos hybrid simulation code is used to examine heating and the partition of dissipation energy at the perpendicular heliospheric termination shock in the presence of pickup ions. The simulations are one-dimensional in space but three-dimensional in field and velocity components, and are carried out for a range of values of pickup ion relative density. Results from the simulations show that because the solar wind ions are relatively cold upstream, the temperature of these ions is raised by a relatively larger factor than the temperature of the pickup ions. An analytic model for energy partition is developed on the …
Scale-Dependent Angle Of Alignment Between Velocity And Magnetic Field Fluctuations In Solar Wind Turbulence, J. J. Podesta, Benjamin D.G. Chandran, A. Bhattacharjee, D. A. Roberts, M. L. Goldstein
Scale-Dependent Angle Of Alignment Between Velocity And Magnetic Field Fluctuations In Solar Wind Turbulence, J. J. Podesta, Benjamin D.G. Chandran, A. Bhattacharjee, D. A. Roberts, M. L. Goldstein
Physics & Astronomy
Under certain conditions, freely decaying magnetohydrodynamic (MHD) turbulence evolves in such a way that velocity and magnetic field fluctuations delta v and delta B approach a state of alignment in which delta v proportional to delta B. This process is called dynamic alignment. Boldyrev has suggested that a similar kind of alignment process occurs as energy cascades from large to small scales through the inertial range in strong incompressible MHD turbulence. In this study, plasma and magnetic field data from the Wind spacecraft, data acquired in the ecliptic plane near 1 AU, are employed to investigate the angle theta(tau) between …