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Infrared, submillimeter, and millimeter observations of the soft gamma-ray repeaters
Waters, L. B. F. M.; Hurley, K.; Kouveliotou, C. +9 more
The Soft Gamma-Ray Repeaters appear to be a completely new manifestation of neutron stars. SGR 1806-20 and SGR 1900+14 may have highly unusual stellar counterparts, whose spectra peak in the far infrared. They have not been detected at submillimeter or millimeter wavelengths. Their infrared spectra appear to contain several components: the photosp…
Simulation and methods for the data analysis of the hydrogen-deuterium-absorption-cell-experiment on Cassini
Reulke, R.; Warlich, K.; Jahn, H.
The Hydrogen-Deuterium-Absorption-Cell (HDAC) will be flown as part of the UltraViolet Imaging Spectrograph on the Cassini mission with the objective to determine the deuterium-to-hydrogen (D/H) ratio in the exosphere of Titan. The HDAC is a photometer designed to measure separately the H and D resonant scattered solar Lyman alpha radiation. A non…
Verifying the accuracy of the third interplanetary network: localization of the bursting pulsar GRO J1744-28 by triangulation
Cline, T.; Hurley, K.; Kouveliotou, C. +8 more
The bursting pulsar GRO J1744-28 is the first repeating source of intense bursts whose position is accurately known, which has become active since the establishment of the third interplanetary network. We show how observations of this object with Ulysses and BATSE can be used to verify many aspects of the triangulation method. Analysis of the prel…
Acceleration in energetics ions (~1MeV) in corotating interaction regions
Balogh, A.; Forsyth, R. J.; Goldstein, B. E. +4 more
We have correlated the ~1 MeV proton intensity (J) measured at corotating reverse shocks detected by Ulysses near the ecliptic plane and in the southern hemisphere with the shock strength and shock normal angle. We find that J is essentially independent of the shock strength below 29 degS, whereas between 29 deg and 41 degS J showed a good correla…
Rapid continuum variability in NGC 4151
Crenshaw, D. M.; Malkan, M.; Warwick, R. +4 more
Intensive monitoring of NGC 4151 showed strong, correlated variability at X-ray, ultraviolet, and optical wavelengths. The strongest variations were seen in ~1.5 keV X-rays, with weaker variations at ~100 keV and no significant variability in the 0.1-1 keV bands. In the ultraviolet/optical regime, the fractional variability amplitude decreased fro…
The shape of a sublimating ice surface at the bottom of a non-volatile cylinder: Monte Carlo simulations and 2-D analysis
Keller, H. U.; Markiewicz, W. J.; Skorov, Yu. V.
Gas flow rate at a cometary surface depends on the microscopic structure of the porous dust-ice material that makes up the nucleus. The standard model for the structure of such material is a bundle of cylindrical, non-crossing tubes. Even within this idealized model the emergent flux depends on the shape of the sublimating ice surface at the botto…
First results from UVCS/SOHO
Romoli, M.; Raymond, J. C.; Naletto, G. +20 more
We present here the first results obtained by the Ultraviolet Coronagraph Spectrometer (UVCS) operating on board the SOHO satellite. The UVCS started to observe the extended corona at the end of January 1996; it routinely obtains coronal spectra in the 1145 A˚ - 1287 A˚, 984 A˚ - 1080 A˚ ranges, and intensity data in the visible continuum. Through…
The modelling of the latitude dependence of cosmic ray protons and electrons in the inner heliosphere
Potgieter, M. S.; Heber, B.; Ferrando, P. +1 more
Observations during the fast latitude scan of Ulysses show that the latitude dependence of cosmic ray protons is significantly less than predicted by drift models which were based on the Parker geometry for the heliospheric magnetic field (HMF) and diffusion coefficients ~ 1/B_p. Recent modeling with a modified HMF and enhanced turbulence in the p…
ULYSSES observations of intermittent heliospheric turbulence
Balogh, A.; Horbury, T. S.; Forsyth, R. J. +1 more
Structure function measurements of small scale magnetic field fluctuations in high speed streams emanating from the Sun's polar coronal holes are well described by a multifractal model of intermittent turbulence. We discuss structure functions and present measurements of intermittency through the transition regime - encompassing scales between wav…
SATI: a spectral airglow temperature imager
Rodrigo, R.; Wiens, R. H.; Moise, A. +6 more
An empirical understanding of planetary scale perturbations in the upper atmosphere is most effectively gained by the complementary use of both satellite and ground-based instrumentation. Limb observations from space provide vertical information and broad global coverage, while ground-based observations provide detailed system development in both …