Search Publications
IUE Short-Wavelength High-Dispersion Line List for the Symbiotic Nova RR Telescopii
Aufdenberg, Jason P.
An 820 minute and other long-exposure archival SWP IUE high-dispersion spectra of symbiotic star RR Tel have been combined to form a composite spectrum. In most of these spectra many lines are saturated, but weaker features appear above the continuum. Their wavelengths were measured from the composite spectrum and compared with the line list from …
Ultraviolet Spectroscopy of Herbig-Haro Objects: Spatial Structure, Spectroscopic Diagnostics, and Variability
Noriega-Crespo, A.; Boehm, K. -H.; Solf, J.
Using new long-exposure (two-shift) SWP IUE spectra of HH 2G, (HH 2H + HH 2A'), and HH 1F and archival spectra of (HH 2H + HH 2A') and of HH 1 we have obtained the following results:
1. For the first time we have determined a separate UV spectrum of the high-excitation condensation HH 2G. The spectrum shows similarity to that of HH 2R. Howeve…Detection of a White Dwarf Compensation to the Hyades Stars HD 27483
Boehm-Vitense, Erika
We observed with IUE a white dwarf (WD) companion to the Hyades F6 V binary stars HD 27483. This system is known to be a close binary of two nearly equal stars with an orbital period of 3.05 days. Our IUE observations revealed the presence of a third star, a white dwarf with an effective temperature of 23,000 +/- 1000 K and a mass of approximately…
The extended nebulosity in the radio galaxy 3C 227.
Walsh, J. R.; Prieto, M. A.; di Serego Alighieri, S. +1 more
3C 227 (z = 0.085) exhibits one of the more spectacular extended nebulosities to be found among active galaxies at moderate redshifts. The gas can be traced to radial distances of about 100 kpc (H_0_ = 50 km s^-1^ Mpc^-1^). The total [O III] 5007-A luminosity is 2.7 X 10^42^ erg s^-1^, of which at least 50 per cent is radiated from the extended re…
The accreting circumstellar gas envelope of HD 176386 a young star inthe R Coronae Austrinae star formation region.
Grady, C. A.; Perez, M. R.; The, P. S.
We report recent and archival IUE observations of the Herbig Be star HD 176386. We find accreting gas toward the star with velocities up to +300 km s-1 in C IV and Si IV. Detection of these species in a B9.5 star is consistent with collisional ionization of the accreting gas to temperatures in excess of the stellar Teff. The …
R 40 : the first luminous blue variable in the Small Magellanic Cloud.
Stahl, O.; Bouchet, P.; Zickgraf, F. -J. +3 more
During the past decade R 40 in the SMC has brightened in the visual range by about 0.5 magnitudes. Correlated with the brightening the spectral type has changed from B8Ia to A3Ia-O. This behaviour shows R 40 to be an LBV, the first one discovered in the SMC. During the past eight years we obtained extensive Stromgren photometry. R 40 was also obse…
Compact subarcsec structures of the double nucleus of NGC 6240 revealed with HST.
Boksenberg, A.; Barbieri, C.; Weigelt, G. +18 more
We have used the Faint Object Camera on board of the Hubble Space Telescope to obtain a high spatial resolution ultraviolet image of the central region of NGC 6240. This image resolves the well known double nucleus of the galaxy into several compact knots with sizes 0.1"-0.2" (about 45-90 pc for H_0_ = 75 km s^-1^Mpc^-1^) and extended low surface …
The Distant Future of Solar Activity: A Case Study of beta Hydri. II. Chromospheric Activity and Variability
Gahm, G. F.; Fredga, K.; Linde, P. +1 more
A detailed comparison of the present sun with the very old star Beta Hyi (G2 IV) is presented in order to study the secular evolution of solar-type chromospheres, with emphasis placed on chromospheric features and their time variability. High-resolution Ca II H and K profiles show the emission to be about half that for the sun, but with the same s…
The Abundances of the Elements in Sharp-lined Early-Type Stars from IUE High-Dispersion Spectrograms. I. Cr, Mn, Fe, Ni, and CO
Adelman, Saul J.; Wahlgren, Glenn M.; Leckrone, David S. +2 more
The current study was undertaken to test the viability of lUE archives as a source of information on elemental species unavailable from (ground-based) coudé spectra. The first step in this endeavor is to check the consistency of abundances obtained from lUE material and those derived from the ground especially as reported in a series of papers by …
The Spectrum of the Planetary Nebula NGC 6567
Feibelman, Walter A.; Hyung, Siek; Aller, Lawrence H.
Because of the similarity of its spectrum to that of NGC 6572 particularly in the UV we have made a detailed study of NGC 6567 using both the IUE for the UV region and the Hamilton Echelle at Lick Observatory for the optical region. Plasma diagnostics suggest an electron temperature of about 11,500K and an electron density near 9000 cm^-3. The che…