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Extremely Active Long-Period RS CVn Binary HD 12545
Fekel, Francis C.; Aufdenberg, Jason P.; Bopp, Bernard W. +2 more
The active-chromosphere giant HD 12545 is noteworthy for its remarkable 1990 photmetric amplitude of 0.6 mag in V, which implies that nearly half the visible hemisphere of the star was covered by cool spots. We report the results of a spectroscopic study of HD 12545, showing it to be an active-chromosphere binary with an orbital period of 23.97 da…
Indications for common origin and gravitational interaction in three binary LMC clusters.
Kontizas, M.; Kontizas, E.; Michalitsianos, A.
Three close pair clusters of the LMC, NGC 2006/SL 538, NGC 2011a/b and NGC 2042a/b, have been studied in order to establish their binarity. The stellar content in the outer region of each cluster has been investigated by means of low resolution objective UK Schmidt prism spectra, the cores of the clusters have been examined using low resolution in…
Determination of field distortion by a plate-overlap method.
Abad, C.
An automated reduction method for determining field distortion common to all plates based on a black-adjustment method proposed by Stock (1981) is demonstrated on the Paris Zone of the Astrographic Catalog. It is shown that the FK5 is suitable as the only reference source for zone catalogs.
The chemical compositions of Algol systems - V. Confirmation of carbon deficiencies in the primaries of eight systems.
Lambert, D. L.; Lemke, M.; Tomkin, J.
We use low-noise CCD spectra of 4267-Å C II line in the spectra of eight Algol-type eclipsing binaries to measure the C abundances of their primaries. A differential LTE analysis of the Algol binaries with respect to single standard stars of the same spectral type shows marginal to moderate deficiencies of C in the primaries of the binaries. We fi…
Introduction to the Ulysses encounter with Jupiter
Smith, Edward J.; Wenzel, Klaus-Peter
The Ulysses spacecraft encountered Jupiter in February 1992, passing within 6.31 radii of the planet. For approximately 8 days it was inside the Jovian magnetosphere, and for several days before and after that, Ulysses was in the interaction regions formed by the solar wind (the magnetosheath and boundary layer). The inbound trajectory was at a ~1…
The First Detection of a Collapsed Core Globular Cluster in M31
Cacciari, C.; Federici, L.; Ferraro, F. R. +6 more
We report on the observations of a globular cluster (designated G105 = Bo 343) in the nearby spiral galaxy M 31, using the Hubble Space Telescope (HST). Image deconvolutions using three different methods indicate that this cluster has a density profile with the morphology characteristic of stellar systems which have undergone core collapse, i.e., …
Three-dimensional particle anisotropies in and near the plasma sheet of Jupiter observed by the EPAC experiment onboard the Ulysses spacecraft
Krupp, N.; Fränz, M.; Dougherty, M. K. +3 more
During its inbound journey into Jupiter's magnetosphere, Ulysses had several encounters with the Jovian plasma sheet near the magnetic equator, which were related with intensity maxima in the energetic particles. We show for the first time anisotropies in three dimensions of three ion species (protons, helium and oxygen) in the energy range 0.24 &…
A Spectroscopic Search for Colliding Stellar Winds in O-Type Close Binary Systems. III. 29 UW Canis Majoris
Wiggs, Michael S.; Gies, Douglas R.
The orbital-phase variations in the optical emission lines and UV P Cygni lines of the massive O-type binary 29 UW Canis Majoris are investigated in a search for evidence of colliding winds. High SNR spectra of the H-alpha and He I 6678-A emission lines are presented, and radial velocity curves for several features associated with the photosphere …
An interpretation of the broadband VLF waves near the Io torus as observed by Ulysses
Kaiser, M. L.; Desch, M. D.; Farrell, W. M. +3 more
The requirements for the Ulysses trajectory to attain high ecliptic latitudes using a Jovian gravitational assist resulted in a fortuitous passage through the Io torus region. Specifically, the spacecraft spend may hours at latitudes just above the torus. During this time the low-frequency cutoff of an ordinary mode (O mode) emission allowed a det…
Wind Variability in the Large Magellanic Cloud B[e] Supergiant HD 34664
Clayton, G. C.; Schulte-Ladbeck, R. E.
We present optical linear spectropolarimetry of the B[e] supergiant HD 34664. The polarization and position angle display significant spectral features which correspond to the Hα and Hβ emission lines. We use the line polarizations to separate the interstellar foreground polarization from the intrinsic polarization of HD 34664. The intrinsic polar…