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ORFEUS echelle spectra: Molecular hydrogen in disk, IVC, and HVC gas in front of the LMC
de Boer, K. S.; Marggraf, O.; Bluhm, H. +1 more
In front of the LMC molecular hydrogen is found in absorption near 0 km s-1, being local disk gas, near +60 km s-1 in an intermediate velocity cloud, and near +120 km s-1, being a high velocity halo cloud. The nature of the gas is discussed based on four Orfeus far UV spectra of LMC stars and including data from th…
The Anomalous Infrared Emission of Abell 58
Kimeswenger, Stefan; Koller, Josef
We present a new model to explain the excess in mid- and near-infrared emission of the central, hydrogen-poor dust knot in the planetary nebula (PN) Abell 58. Current models disagree with ISO measurements because they apply an average grain size and equilibrium conditions only. We investigate grain size distributions and temperature fluctuations a…
High resolution spectroscopy of symbiotic stars. VI. Orbital and stellar parameters for AR Pavonis
Schmutz, W.; Nussbaumer, H.; Schild, H. +3 more
We present new dynamical parameters of the AR Pav binary system. Our observations consist of a series of high resolution optical/NIR spectra from which we derive the radial velocity curve of the red giant as well as its rotation velocity. Assuming co-rotation, we determine the stellar radius (130 Rsun) of the red giant. Based on this we…
An X-ray selected sample of radio-loud quasars
Wolter, A.; Celotti, A.
We construct the first X-ray selected sample of broad line radio-loud AGN from the EMSS survey. In order to test unifying schemes for radio-loud objects, their spectral and statistical properties (both flat and steep spectrum objects) are examined and compared with those of other samples of blazars. The X-ray selection allows us to explore propert…
Interplanetary magnetic field: Statistical properties and discrete modes
Lanzerotti, L. J.; Maclennan, C. G.; Thomson, D. J.
We report here detailed statistical studies of power spectra of 1 hour average interplanetary magnetic field (IMF) data that were acquired by the magnetometer instrument on the Ulysses spacecraft in the ecliptic plane of the heliosphere during Ulysses' cruise phase from Earth to Jupiter (October 1990 through January 1992). We have pursued these st…
Sharp Decreases of Solar Metric Radio Storm Emission
Kahler, S.; Aurass, H.; Chertok, I. M. +1 more
We discuss a little-known variety of sharp decreases of long-duration meter-wavelength noise storms and type IV bursts. A survey of the IZMIRAN and AIP radio observations shows that a decrease or nearly complete disappearance of the continuum and bursts developing over tens of minutes without a subsequent recovery of the radio flux occasionally oc…
Stream Interaction Regions at High Heliographic Latitudes During Ulysses12/22/2004 6:25PM Second Polar Orbit
McComas, D. J.; Forsyth, R. J.; Gosling, J. T. +1 more
Ulysses observed well-defined stream interaction regions, SIRs, associated with solar wind stream structure up to a latitude of S65° and shocks to at least a latitude of S71° during the second polar orbit. These SIRs and shocks produced a substantial heliospheric processing of the solar wind. Only a subset of the SIRs recurred on successive solar …
Evidence for an Accelerating Wind as the Broad-Line Region in NGC 3516
Zheng, W.; Kriss, G. A.; Koratkar, A. P. +4 more
Spectroscopic data in wavelengths 900-3000 Å have been obtained in a low flux state of the nucleus of the Seyfert 1 galaxy NGC 3516. The line profiles show P Cygni characteristics, particularly in O VI λ1032, and are compared with data from an earlier and higher state. The profiles are suggestive of and consistent with an accelerating wind driven …
A search for previously unrecognized metal-poor subdwarfs in the Hipparcos astrometric catalogue
Reid, I. Neill; Kilkenny, D.; Marang, F. +3 more
We have identified 317 stars included in the Hipparcos astrometric catalogue that have parallaxes measured to a precision of better than 15 per cent, and the location of which in the (MV,(B-V)T) diagram implies a metallicity comparable to or less than that of the intermediate-abundance globular cluster M5. We have undertaken …
Cosmic-ray Composition as Observed by Ulysses
Connell, James J.
The cosmic ray isotopic composition measurements from the High Energy Telescope (HET) on the Ulysses spacecraft are reviewed. The source isotopic composition of key elements is found to be surprisingly like the Solar system abundances with the notable exception of ^22Ne. The average density of interstellar material cosmic rays traverse is found to…