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The Identification and Characterization of Alfvénic Fluctuations in ULYSSES Data at Midlatitudes
Balogh, A.; Lucek, E. A.
Ulysses magnetic field and plasma data recorded during 1992 and 1993 as the spacecraft moved through mid-heliolatitudes, have been used to identify intervals dominated by Alfvénic fluctuations in the presence of corotating interaction regions. A wavelet frame representation of Elsässer variables was used to calculate the Alfvénicity of the fluctua…
Doppler imaging of stellar surface structure. VIII. The effectively single and rapidly-rotating G8-giant HD 51066 = CM Camelopardalis
Strassmeier, K. G.; Weber, M.; Washuettl, A. +2 more
We present first Doppler images of HD 51066 from observations in 1994, 1995, 1996 and 1997, and find evidence for a vanishing polar spot in accordance with the system's long-term brightness increase. Several small spots with Delta T~500 K appear also at low latitudes. Our cross-correlation maps indicate a latitude-dependent phase-shift pattern bet…
SUMER Observations of the Evolution and the Disappearance of a Solar Prominence
Kucera, T. A.; Ofman, L.; Mouradian, Z. +1 more
The mechanisms that lead to the formation and the disappearance of prominences are poorly understood, at present. An arch-shaped prominence was observed with the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on board the Solar and Heliospheric Observatory (SOHO) on 31 March-1 April 1996. The observations were performed a…
The Ages of Disturbed Field Elliptical Galaxies. II. Central Properties
Silva, David R.; Bothun, Gregory D.
The formation of elliptical galaxies via the merger of gas-rich disks has received considerable attention in recent years, with many studies strongly supporting the merger hypothesis. When investigated in detail, the dynamics of a major merger that produces a high phase-space density of material (e.g., the center of an elliptical galaxy) invariabl…
The physical parameters of the evolving population of faint galaxies
Ellis, Richard; Glazebrook, Karl; Abraham, Roberto +2 more
The excess number of blue galaxies at faint magnitudes is a subject of much controversy. Recent Hubble Space Telescope results have revealed a plethora of galaxies with peculiar morphologies tentatively identified as the evolving population. We report the results of optical spectroscopy and near-infrared photometry of a sample of faint HST galaxie…
The ultraviolet spectrum of the narrow-line Seyfert 1 galaxy RE J1034+396
Siemiginowska, A.; Mason, K. O.; Puchnarewicz, E. M.
RE J1034+396 has one of the hottest big blue bumps of any Seyfert 1 (kT_BB~120 eV) and thus provides a valuable insight into the physics in the nuclei of active galaxies. In this paper, we present UV spectroscopy of RE J1034+396, taken with the Faint Object Spectrograph on the Hubble Space Telescope. With a spectral resolution of ~1-2 Angstroms FW…
The Ultraviolet-Optical Albedo of Broad Emission Line Clouds
Korista, Kirk; Ferland, Gary
We explore the effective UV-optical albedos of a variety of types of broad emission line clouds, as well as their possible effects on the observed spectra of active galactic nuclei (AGNs). An important albedo source in moderately ionized ionization-bounded clouds is that which is due to neutral hydrogen: Rayleigh scattering of continuum photons of…
O5+ in High Speed Solar Wind Streams: SWICS/Ulysses Results
Wimmer-Schweingruber, Robert F.; Gloeckler, George; Geiss, Johannes +3 more
Recent observations with UVCS on SOHO of high outflow velocities of O5+ at low coronal heights have spurred much discussion about the dynamics of solar wind acceleration. On the other hand, O6+ is the most abundant oxygen charge state in the solar wind, but is not observed by UVCS or by SUMER because this helium-like ion has …
The PL relation of galactic carbon LPVs. The distance modulus to LMC
Bergeat, J.; Knapik, A.; Rutily, B.
We present a period-luminosity (PL) diagram of 115 galactic carbon-rich long period variables (LPVs) observed by the HIPPARCOS satellite, in the form of the (MK,log P) relation. Our plot is compared to the diagram of carbon variables observed in the Large Magellanic Cloud (LMC). Both diagrams are found very similar and three samples are…
Below the Lyman Edge: Ultraviolet Polarimetry of Quasars
Antonucci, Robert; Koratkar, Anuradha; Storrs, Alex +1 more
The Lyman edge at 912 Å is an important diagnostic region for studying quasi-stellar objects (QSOs). In particular, it reveals a great deal about the physical conditions within the atmospheres of accretion disks, a ubiquitous component of QSO theories. A robust prediction of accretion disk models is a significant polarization due to electron scatt…