Structure of the hot object in the symbiotic prototype Z Andromedae during its 2000-03 active phase

Aims.To investigate structure of the hot object in the symbiotic prototype Z And during its major 2000-03 active phase.
Methods: .Analysis of the far ultraviolet, optical low- and high-resolution spectroscopy and {UBVR} photometry. Reconstruction of the spectral energy distribution (SED) during the outburst. The Raman scattering process.
Results: .At the initial stages of the outburst the hot object was characterized by the two-temperature spectrum (a warm stellar radiation and a strong nebular emission) with signatures of a mass-outflow at moderate ( 100-200 km s^-1) and very high (≈1000-2000 km s^-1) velocities. The corresponding structure of the hot object consists of an optically thick, slowly-expanding disk-like material encompassing the accretor at the orbital plane and a fast optically thin wind over the remainder of the star. The disk-like shell persisted around the central star until 2002 August as was indicated by the eclipse effect. Then, a significant dilution of the optically thick material and evolution of a fast wind from the hot star, concentrated more at the orbital plane, were detected. A striking similarity of [Fe VII] λ6087 and Raman λ6825 profiles at/after the dilution of the disk suggests their origin within the interaction zone where the winds from the binary components collide.