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The aims of our study are to improve the orbital elements of the giant and to derive the spectroscopic orbit for the white dwarf companion. Spectral variations related to the 2006 outburst are also studied. The spectroscopic orbits have been obtained by measuring the radial velocities of the cool component absorption lines and the broad Halpha emission wings, which seem to be associated with the hot component. A set of cF-type absorption lines were also analyzed for a possible connection with the hot component motion. A new period of 453.6 days and a mass ratio, q=M_g/M_h=0.59 were determined. Assuming a massive white dwarf as the hot component, M_h= 1.2-1.4 M_{\odot}, the red giant mass is M_g= 0.68-0.80 M_{\odot} and the orbit inclination, i = 49-52^{\circ}. The cF-type lines are not associated with either binary component, and are most likely formed in the material streaming towards the hot component. We also confirm the presence of the LiI doublet in RS Oph and its radial velocities fit very well the M-giant radial velocity curve. Regardless of the mechanism involved to produce lithium, its origin is most likely from within the cool giant rather than material captured by the giant at the time of the nova explosion. In April 2006 most of the emission lines present a broad pedestal with a strong and narrow component at about -20 km/s and two other extended emission components at -200 and +150 km/s. These components could originate in a bipolar gas outflow supporting the model of a bipolar shock-heated shell expanding through the cool component wind perpendicularly to the binary orbital plane., Comment: 12 pages, 10 figures, 4 tables. Astronomy & Astrophysics (accepted)

We present an analysis of optical and near infrared spectra of the eclipsing symbiotic system FN Sgr. In particular, we have determined for the first time spectroscopic orbits based of the radial velocity curves for both components. A set of blue absorption lines resembling an A-F type star is present in all our spectra. They seem to be associated with the hot component but the best orbital fitting corresponds to a larger eccentricity. We have also studied spectral changes and photometric variations in function of both the hot component activity and the orbital motion., Comment: 4 pages, 2 Postscript figures. Submitted to Conference proceeding Symbiotic stars probing stellar evolution. ASP Conference Series. R.L.M. Corradi, J. Mikolajewska, T.J. Mahoney, eds., in press

We present an analysis of optical and near infrared spectra of the symbiotic system AE Ara, composed of an M5.5 III giant similar to the Galactic Bulge M giants and a hot luminous companion. In particular, we have determined for the first time spectroscopic orbits based of the radial velocity curves for the red and the hot component from the M-giant absorption lines and from the wings of He II 4686 emission profiles, respectively. We have also studied spectral changes and photometric variations in function of both the orbital phase and activity. The resulting physical parameters of the binary components and the nature of the hot component activity are briefly discussed., Comment: 4 pages, 2 figures. To appear in 'Symbiotic stars probing stellar evolution', eds. R.M.L. Corradi, J. Mikolajewska, T. Mahoney

A study of the available archival IUE images of Beta Lyrae has led to the following results: (1) for lambda in the range of 1250 - 1500 A, the eclipse depth at second conjunction is slightly larger than the eclipse depth at primary conjunction; they are equal at about 1670 A; (2) the profiles of the resonance lines of SiIV (and the same seems to be true for NV and CIV) can be described as composite, formed by the superposition of a stationary P Cygni profile that suggests a velocity of approach of -170 km/s and a broad, less strong, emission that seems to yield a velocity distribution in antiphase with the velocity curve of the B8 II component of the system; and (3) the emission lines of the intercombination doublet of semiforbidden N II at about 2140 A suggest a velocity of about -130 km/s. The interpretation of the latter composite profile appears similar to the one suggested by Sahade (1966) to describe H-alpha and He I 5876 and He I 6678, and by Batten and Sahade (1973) to describe H-alpha.