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Full-Text Articles in Astrophysics and Astronomy
Fe Ii Fluorescence And Anomalous C Iv Doublet Intensities In Symbiotic Novae, A. G. Michalitsianos, Menas Kafatos, S. R. Meier
Fe Ii Fluorescence And Anomalous C Iv Doublet Intensities In Symbiotic Novae, A. G. Michalitsianos, Menas Kafatos, S. R. Meier
Mathematics, Physics, and Computer Science Faculty Articles and Research
Symbiotic stars frequently exhibit anomalous C IV λλ1548.2, 1550.8 doublet flux ratios, in which the intensity ratio of the blue and red doublet members is below the optically thick limit of unity. Three symbiotic stars (RR Tel, RX Pup, and AG Peg) have been investigated in detail with high-resolution spectra obtained from the International Ultraviolet Explorer (IUE) archives. We have examined the deficit of C IV λ1548.2 emission relative to λ1550.8 in context with the fluorescent pumping of the Fe II multiplet (45.01) λ1548.204 by the C IV λ1548.2 line. In RR Tel the C IV λ1548.2 flux is correlated …
R Aquarii: The Large-Scale Optical Nebula And The Mira Variable Position, A. G. Michalitsianos, R. J. Oliverson, J. M. Hollis, Menas Kafatos, H. E. Crull, R. J. Miller
R Aquarii: The Large-Scale Optical Nebula And The Mira Variable Position, A. G. Michalitsianos, R. J. Oliverson, J. M. Hollis, Menas Kafatos, H. E. Crull, R. J. Miller
Mathematics, Physics, and Computer Science Faculty Articles and Research
The R Aquarii symbiotic star system is surrounded by a large-scale optical nebula. We present observations of the nebular [O III] structure and discuss its morphological significance in context with previously observed small-scale radio-continuum features, which may be related. We suggest that a precessing accretion disk may explain the global features of both the large-scale optical emission and the small-scale radio emission. Moreover, we have determined an accurate position of the system's Mira, which suggests that a recent theoretical model, yielding an egg-shaped central H II region for symbiotic systems with certain physical parameters, may apply to R Aquarii. The …
Observations Of Two Peculiar Emission Objects In The Large Magellanic Cloud, Menas Kafatos, A. G. Michalitsianos, D. A. Allen, R. E. Stencel
Observations Of Two Peculiar Emission Objects In The Large Magellanic Cloud, Menas Kafatos, A. G. Michalitsianos, D. A. Allen, R. E. Stencel
Mathematics, Physics, and Computer Science Faculty Articles and Research
Ultraviolet and visual wavelength spectra were obtained of two peculiar emission objects, Henize S63 and Sanduleak.'s star in the Large Magellanic Cloud. Previously not observed in the near- or far-ultraviolet, both objects exhibit strong permitted and semiforbidden line emission. Estimates based on the absolute continuum flux of the hot companion star in Hen S63 indicate that it rivals the luminosity of the carbon star primary. The emission-line profile structure in both objects does not suggest Wolf-Rayet type emission. Carbon in Sanduleak.'s star (LMC anonymous) is conspicuously absent, while N v, N IV], and N III] dominate the UV emission-line spectrum. …