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Analysis of IUE Spectra for the Star V1016 Ori
Vitrichenko, É. A.
Survey of MeV proton anisotropies measured by Ulysses
Balogh, André; Dalla, Silvia
The Anisotropy Telescopes (ATs) instrument, part of the COSPIN experiment on board Ulysses, measures fluxes and anisotropies of protons in the MeV range. We survey data from this instrument throughout the Ulysses mission, with particular emphasis on solar maximum, when large particle intensities were measured. The only significant fluxes detected …
Time-dependent 3-D modelling of the heliospheric propagation of few-MeV electrons
Fichtner, H.; Ferreira, S. E. S.; Potgieter, M. S. +2 more
With a recently developed steady-state model of the propagation of Jovian and galactic electrons in the inner three-dimensional heliosphere we were able to demonstrate both the necessity and value of such modelling for (i) the determination of the diffusion tensor of energetic particles, (ii) an observational discrimination between Jovian and inte…
Coronal Heating and Solar Wind Acceleration: Future Work on Observations
Peter, Hardi
The space-based observatories SOHO and TRACE have shown some very interesting results on the structure and dynamics of the Sun and its atmosphere, e.g., the extremely high ion temperatures or the enormous variability in the corona. But one question is still open to debate: how to use these data to distinguish between different types of physical he…
What can HST-GHRS Fe II observations of α Orionis (M2 Iab) tell us about short-period heating?
Cuntz, M.; Harper, G. M.; Bennett, P. D.
Cuntz (\cite{Cuntz97}) suggested that apparent velocity shifts in Fe II emission lines observed in Betelgeuse (alpha Orionis: M2 Iab) indicate that non-magnetic wave modes are relevant for the heating and dynamics of alpha Ori's chromosphere. This claim was based on the similarity of computed stochastic velocities in 1-D short-period acoustic wave…
Measurements of Rotational Frequency Splitting of Low Angular Degree Modes
Toutain, Thierry
The rotational splitting of low-degree p modes is still a controversial issue. There are small but nevertheless real discrepancies between the different measurements of splittings obtained with the existing helioseismology experiments from ground (BISON, IRIS, GONG, LOWL) or from space (VIRGO, GOLF, MDI). I review the current status of rotational …
Private life of an integrating sphere: the radiant homogeneity of the Descent Imager -Spectral Radiometer calibration sphere
Rizk, Bashar
Perturbations to an integrating sphere's radiant uniformity by a protruding optical system are mapped. A sphere provides the Descent Imager-Spectral Radiometer sensor head (DISR SH), a practical platform for many of its subsystems' calibrations, but the resulting nonuniformity threatens the goal of accurate radiometry. An apparatus with a nearly i…
Intensities of galactic cosmic ray nuclei from the ecliptic to the south solar polar regions near solar maximum: observations from the ULYSSES COSPIN high energy telescope
Heber, B.; McKibben, R. B.; Zhang, M. +2 more
Ulysses reached its maximum south heliographic latitude of 80.2° S in late November 2000, near the maximum in the solar activity cycle and is now embarked on a fast latitude scan that will bring it to a perihelion at 1.34 AU near the solar equator by mid-May 2001. Throughout the period of increasing solar activity since Ulysses left the ecliptic i…
Observations of the Acceleration of Polar Solar Wind Near Solar Maximum
Simnett, G. M.; Tappin, S. J.; Lyons, M. A.
In a previous paper (Tappin et al., 1999) we used cross-correlation analysis of high-cadence observations with the LASCO coronagraphs to trace the acceleration of the solar wind at low latitudes. In this paper we present a similar analysis carried out over the North pole of the Sun. The observations which were made in March 2000 with the C3 corona…
Ulysses High Energy Telescope Measurements of the Isotopic Abundances of Galactic Cosmic Rays for Elements between C and Fe with Estimates of the Source Composition
Connell, J. J.
We report new and revised high resolution measurements of the isotopic composition of Galactic cosmic rays in the Solar system using data from the High Energy Telescope (HET) on the Ulysses Spacecraft. These data have significantly improved statistics compared with our earlier measurements. Mass resolution varies from ~0.08 to ~0.31 u at observed …