Search Publications
Neutral Interstellar Helium Parameters Based on IBEX-Lo Observations and Test Particle Calculations
Bochsler, P.; McComas, D. J.; Fuselier, S. A. +10 more
Because of its high ionization potential and weak interaction with hydrogen, neutral interstellar helium (NISHe) is almost unaffected at the heliospheric interface with the interstellar medium and freely enters the solar system. This second most abundant species provides some of the best information on the characteristics of the interstellar gas i…
On Spectral Breaks in the Power Spectra of Magnetic Fluctuations in Fast Solar Wind between 0.3 and 0.9 AU
Maksimovic, M.; Alexandrova, O.; Marsch, E. +1 more
We analyze the radial variation of the power spectra of the magnetic field from 0.3 to about 0.9 AU, using Helios 2 spacecraft measurements in the fast solar wind. The time resolution of the magnetic field data allows us to study the power spectra up to 2 Hz. Generally, the corresponding spectral break frequency fb and the Doppler-shift…
A unique volcanic field in Tharsis, Mars: Pyroclastic cones as evidence for explosive eruptions
Hauber, E.; Brož, P.
Based on theoretical grounds, explosive basaltic volcanism should be common on Mars, yet the available morphological evidence is sparse. We test this hypothesis by investigating a unique unnamed volcanic field north of the shield volcanoes Biblis Patera and Ulysses Patera on Mars, where we observe several small conical edifices and associated lava…
Three-dimensional Evolution of Solar Wind during Solar Cycles 22-24
Manoharan, P. K.
This paper presents an analysis of three-dimensional evolution of solar wind density turbulence and speed at various levels of solar activity between solar cycles 22 and 24. The solar wind data used in this study have been obtained from the interplanetary scintillation (IPS) measurements made at the Ooty Radio Telescope, operating at 327 MHz. Resu…
Systematic Investigation of Solar Modulation of Galactic Protons for Solar Cycle 23 Using a Monte Carlo Approach with Particle Drift Effects and Latitudinal Dependence
Boella, G.; Gervasi, M.; Grandi, D. +8 more
A propagation model of galactic cosmic protons through the heliosphere was implemented using a two-dimensional Monte Carlo approach to determine the differential intensities of protons during solar cycle 23. The model includes the effects due to the variation of solar activity during the propagation of cosmic rays from the boundary of the heliopau…
On the Occurrence of the Third-order Scaling in High Latitude Solar Wind
Bruno, R.; Carbone, V.; Veltri, P. +3 more
The occurrence and nature of a nonlinear energy cascade within the intermediate scales of solar wind Alfvénic turbulence represents an important open issue. Using in situ measurements of fast, high latitude solar wind taken by the Ulysses spacecraft at solar minima, it is possible to show that a nonlinear energy cascade of imbalanced turbulence is…
Time-dependent MHD modeling of the global solar corona for year 2007: Driven by daily-updated magnetic field synoptic data
Liu, Yang; Wu, S. T.; Feng, X. S. +3 more
In this paper, we develop a time-dependent MHD model driven by the daily-updated synoptic magnetograms (MHD-DUSM) to study the dynamic evolution of the global corona with the help of the 3D Solar-Interplanetary (SIP) adaptive mesh refinement (AMR) space-time conservation element and solution element (CESE) MHD model (SIP-AMR-CESE MHD Model). To ac…
The Solar Wind Energy Flux
Issautier, K.; Meyer-Vernet, N.; Le Chat, G.
The solar-wind energy flux measured near the Ecliptic is known to be independent of the solar-wind speed. Using plasma data from Helios, Ulysses, and Wind covering a large range of latitudes and time, we show that the solar-wind energy flux is independent of the solar-wind speed and latitude within 10 %, and that this quantity varies weakly over t…
The flow of interstellar dust into the solar system
Kempf, S.; Srama, R.; Grün, E. +3 more
Context. Interstellar dust (ISD) is a major component in the formation and evolution of stars, stellar systems, and planets. Astronomical observations of interstellar extinction and polarization, and of the infrared emission of the dust, are the most commonly used technique for characterizing interstellar dust. Besides this, the interstellar dust …
Solar Wind Models from the Chromosphere to 1 AU
Velli, Marco; Hansteen, Viggo H.
Recent models of the fast solar wind are characterized by low coronal electron temperatures while proton, α-particle, and minor ion temperatures are expected to be quite high and generally anisotropic, including large temperatures perpendicular to the magnetic field and parallel beams. This entails that the electric field should be relatively unim…