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An investigation of the B335 region through far infrared spectroscopy with ISO
Liseau, R.; White, G. J.; Benedettini, M. +11 more
We present far infrared spectra of the B335 dark cloud region, obtained with the Long Wavelength Spectrometer (LWS) on-board the ISO satellite. Deep spectra were obtained towards the far infrared outflow exciting source, located in the B335 core, and on the three associated Herbig Haro (HH) objects HH119 A, B and C. In addition, a region of about …
A non-local thermodynamic equilibrium spherical line-blanketed stellar atmosphere model of the early B giant beta CMa
Hauschildt, P. H.; Baron, E.; Aufdenberg, J. P.
The observed multiwavelength spectrum of the B1II--III star beta CMa is successfully reproduced, including the extreme ultraviolet (EUV) continuum observed by Extreme Ultraviolet Explorer (EUVE), with a non-local thermodynamic equilibrium fully line-blanketed spherical hydrostatic model atmosphere. The available spectrophotometry of beta CMa from …
Chromospheric imaging of the active binary system V 711 Tauri = HR 1099 in December 1992
Pagano, I.; Lanzafame, A. C.; Rodonò, M. +2 more
Spectroscopic observations of the bright RS CVn-type system V 711 Tau = HR 1099 (K1 IV + G5 V) were obtained by IUE during the same period of a Multi-Site Continuous Spectroscopy (MUSICOS) campaign between 12-18 December 1992 (Huang et al. 1995). We report on the results of a ``Doppler Imaging" analysis of the Mg II h line. Broad, variable and ext…
Ultraviolet and Optical Line Profile Variations in the Spectrum of ɛ Persei
Kambe, E.; Gies, D. R.; Riddle, R. L. +13 more
The rapid variable star, ɛ Per (B0.5 IV-III), displays the largest amplitude profile fluctuations known among the growing number of massive, spectrum-variable stars. Here we present an analysis of a continuous 5 day run of IUE UV spectroscopy, and we show for the first time that the systematic, blue-to-red moving patterns observed in high-quality …
Lines of OIV and SIV in the Goddard High-Resolution Spectrograph spectrum of RR Tel: constraints on atomic data
Judge, P. G.; Carpenter, K. G.; Jordan, C. +3 more
High signal-to-noise ratio spectra of RR Tel obtained at medium resolution with the Goddard High-Resolution Spectrograph (GHRS) on the Hubble Space Telescope (HST) are used to test available atomic data for the OIV 2s^22p ^2P-2s2p^2 ^4P multiplet (UV 0.01). The fine-structure intervals of the 2s2p^2 ^4P term given by Moore (1983) appear to need re…
Total solar irradiance variations
Fröhlich, C.; Pap, J. M.
Total solar irradiance has been monitored from space for nearly two decades. These space-borne observations have established conclusively that total solar irradiance changes over a wide range of periodicities-from minutes to the 11-year solar cycle. Since the total energy flux of the Sun is the principal driver for all Earths atmospheric phenomena…
SN 1994D in NGC 4526: a normally bright type IA supernova
Richtler, Tom; Drenkhahn, Georg
Application of Realistic Model Atmospheres to Eclipse Maps of Accretion Disks: The Effective Temperature and Flare of the Disk in the Dwarf Nova Z Chamaeleontis
Wood, Janet H.; Wade, Richard A.; Robinson, Edward L.
In a previous paper we presented ultraviolet (λeff=1550 Å) high-speed photometry of the eclipsing dwarf nova Z Cha obtained near the peak of a normal eruption, and we derived a maximum-entropy disk map from the eclipse light curve. In the present paper we report a new calculation of the disk map and temperature profile. The calculation …
Consistency of accretion discs with Seyfert 1 UV fluxes and Hβ emission-line profiles
Boisson, C.; Rokaki, E.
This paper presents accretion disc fits to the UV continuum and Hβ emission line in a complete sample of broad-emission-line AGN sources. Disc fits to the UV continuum emission leave an ambiguity between the central mass and the orientation of the disc in that more massive black holes mimic more edge-on discs. The opposite dependence between mass …
Accurate Optical Positions of Extragalactic Radio Reference Frame Sources
Zacharias, N.; Zacharias, M. I.; Hall, D. M. +3 more
Optical positions on the 50 mas level in the Hipparcos system have been obtained for 327 extragalactic, radio reference frame sources for both hemispheres from a 2-step procedure. Positions of secondary reference stars in the 10<=V<=14 magnitude range were obtained from photographic plates taken at the Hamburg astrograph (Northern Hemisphere…