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ISO LWS Observations of Evolved Stars and Nebulae

Barlow, M. J.

The Hipparcos distances of open clusters and their implication on the local variations of the ΔY/ΔZ ratio.

Zinnecker, H.; Schilbach, E.; Efremov, Yu. N.

Arguments are collected to demonstrate that recent Hipparcos results on the distances of open clusters are in agreement with previous estimates in the Russian literature which have pointed to a shorter distance scale. Evidence of the absence of a universal correlation between helium and metal abundances is given. It is suggested that violations of…

Latitudinal structure of the heliospheric current sheet and corotating streams measured by WIND and ULYSSES

Tsurutani, B. T.; Steinberg, J. T.; Goldstein, B. E. +5 more

All heliospheric current sheet (HCS) crossings and corotating solar wind streams detected by both WIND and Ulysses have been identified. These measurements were made when Ulysses was in its fast latitudinal scan (at a heliocentric radial distance of ∼1.4 AU) and WIND was in the ecliptic plane near the Earth. Instantaneous solar wind velocities are…

Multiwavelength studies of β Cephei stars: δ Ceti.

Cugier, H.; Nowak, D.

We discuss diagnostic aspects that follow from identification of the driving mechanism for the pulsation of β Cephei stars by an analysis of the well-observed star δ Ceti. Ground-based photometric and ultraviolet IUE spectro-photometric observations were used. We find that the stellar model which fits the observed frequency of oscillation and nona…

A 3D Simulation of Intensities along Ulusses' Trajectory

Wibberenz, G.; Heber, B.; Burger, R. A. +1 more

Ion cyclotron waves in the Jovian magnetosphere

Dougherty, M. K.; Southwood, D. J.; Lachin, A.

Magnetic field data from the inbound Ulysses flyby past Jupiter in February 1992 is examined for evidence of ion cyclotron wave activity. Particular interest has been paid to the near equatorial current sheet within the middle magnetosphere where the field magnitude ranges between 5-60 nT. Power spectral peaks in the ion cyclotron range are easily…

A New Color Image of the Crab Nebula

Wainscoat, R. J.; Kormendy, J.

A new color image of the Crab Nebula is presented. This is a 2782 × 1904 pixel mosaic of CCD frames taken through B (blue), V (green), and R (red) filters; it was carefully color balanced so that the Sun would appear white. The resolution of the final image is approximately 0.8 arcsec FWHM. The technique by which this image was constructed is desc…

Direct demodulation image reconstruction of ME/EXOSAT Galactic Plane Survey.

Lu, Fangjun; Wu, Mei; Li, Tibei +1 more

The authors have reanalyzed the ME/EXOSAT Galactic Plane scan observational data with direct demodulation technique. They have studied the discrete X-ray sources in the regions which were unresolved in previous analyses. Using the bootstrap method, they have analyzed the statistical accuracy of the results and determined the position and flux erro…

Effects of High Ion Temperatures on Spectral Line Diagnostics in the Source Region of the High-speed Solar Wind

Esser, R.; Brickhouse, N. S.

Theoretical work on solar wind acceleration has suggested that the proton and electron temperatures at the base of the solar coronal hole region are not thermally equilibrated but that instead the proton temperature may exceed the electron temperature significantly. Recently, Kohl, Strachan, & Gardner have measured both broad and narrow compon…

Synthetic Spectra of Long-Period Variables: A First Comparison with ISO Observations

Aringer, Bernhard; Loidl, Rita; Hron, Josef +3 more

Exploratory synthetic spectra were computed for carbon-rich long-period variables. We used dynamic model atmospheres of Höfner & Dorfi (1997) and calculated partial pressures, absorption- and scattering coefficients as input for the spectral synthesis code of Jørgensen et al. (1992). First ISO SWS-observations of the carbon-Mira T Dra are comp…