Other
Scientific paper
Sep 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993nassp.507..647f&link_type=abstract
In NASA, Washington, Cataclysmic Variables and Related Objects p 647-662 (SEE N95-27068 09-89)
Other
Cataclysmic Variables, Ionization, Radio Observation, Stellar Envelopes, Stellar Models, Stellar Spectra, Symbiotic Stars, Variability, Continuums, Dwarf Novae, Eclipses, Emission Spectra, Infrared Spectra, Nebulae, Stellar Mass Ejection, Visual Observation, X Rays
Scientific paper
One of the most important features of symbiotic stars is the coexistence of a cool spectral component that is apparently very similar to the spectrum of a cool giant, with at least one hot continuum, and emission lines from very different stages of ionization. The cool component dominates the infrared spectrum of S-type symbiotics; it tends to be veiled in this wavelength range by what appears to be excess emission in D-type symbiotics, this excess usually being attributed to circumstellar dust. The hot continuum (or continua) dominates the ultraviolet. X-rays have sometimes also been observed. Another important feature of symbiotic stars that needs to be explained is the variability. Different forms occur, some variability being periodic. This type of variability can, in a few cases, strongly suggest the presence of eclipses of a binary system. One of the most characteristic forms of variability is that characterizing the active phases. This basic form of variation is traditionally associated in the optical with the veiling of the cool spectrum and the disappearance of high-ionization emission lines, the latter progressively appearing (in classical cases, reappearing) later. Such spectral changes recall those of novae, but spectroscopic signatures of the high-ejection velocities observed for novae are not usually detected in symbiotic stars. However, the light curves of the 'symbiotic nova' subclass recall those of novae. We may also mention in this connection that radio observations (or, in a few cases, optical observations) of nebulae indicate ejection from symbiotic stars, with deviations from spherical symmetry. We shall give a historical overview of the proposed models for symbiotic stars and make a critical analysis in the light of the observations of symbiotic stars. We describe the empirical approach to models and use the observational data to diagnose the physical conditions in the symbiotics stars. Finally, we compare the results of this empirical approach with existing models and discuss unresolved problems requiring new observational and theoretical work.
No associations
LandOfFree
Models of symbiotic stars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Models of symbiotic stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Models of symbiotic stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1565298