Abstract.We analyze Hα observations of the recurrent nova T CrB obtained during the last decade. For the first time the Hα emission profile is analyzed after subtraction of the red giant contribution. Based on our new radial velocity measurements of the Hα emission line we estimate the component masses of T CrB. It is found that the hot component is most likely a massive white dwarf. We estimate the inclination and the component masses to be i 67 • , M WD 1.37 ± 0.13 M and M RG 1.12 ± 0.23 M , respectively. The radial velocity of the central dip in the Hα profile changes nearly in phase with that of the red giant's absorption lines. This suggests that the dip is most likely produced by absorption in the giant's wind. Our observations cover an interval when the Hα and the U-band flux vary by a factor of ∼6, while the variability in B and V is much smaller. Based on our observations, and archival ultraviolet and optical data we show that the optical, ultraviolet and Hα fluxes strongly correlate. We argue that the presence of an accretion disc can account for most of the observed properties of T CrB.

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Two-dimensional gas-dynamical modeling of the mass-flow structure is used to study the outburst development in the classical symbiotic star Z And. The stage-by-stage rise of the light during the outburst can be explained in the framework of the colliding winds model. We suggest a scenario for the development of the outburst and study the possible influence of the changes of the flow structure on the light of the system. The model variations of the luminosity due to the formation of a system of shocks are in good agreement with the observed light variations.

High‐resolution observations in the region of the lines Hα, He iiλ 4686 and Hγ of the spectrum of the symbiotic binary Z Andromedae were performed in the quiescent state of the system and also during its outburst phase in 2000–2002. The triplet lines of He i had P Cygni profiles indicating stellar wind with a velocity of 60 km s−1 from the hot secondary. This wind created an absorption dip in the emission profile of the line Hγ. The lines Hγ and He iiλ 4686 had a broad emission component, indicating an optically thin stellar wind with a velocity of about 500 km s−1. The intensity of the broad component reached its maximum together with the optical light. To explain the observations, a model with an accretion disc was proposed, where the velocity of the wind from the accretor is supposed to be 500 km s−1. The accretion disc is responsible for the breaking of the stellar wind close to the orbital plane where its velocity decreases to about 60 km s−1. The mass‐loss rate of the accretor at the time of a maximal light was obtained of 2.4 × 10−7 (d/1.12 kpc)3/2 M⊙ yr−1 and decreased to 1.0 × 10−7 (d/1.12 kpc)3/2 M⊙ yr−1 in 2001 October.