相关论文: Formation of a disk-structure and jets in the symb…
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.…
We present development of the collimated bipolar jets from the symbiotic prototype Z And that appeared and disappeared during its 2006 outburst. In 2006 July Z And reached its historical maximum at U ~ 8.0. During this period, rapid…
We have studied optical spectra of the symbiotic star Z And, obtained during its latest outburst started in April 2006, with the aim of finding changes in the spectrum yielding clues to the nature of the hot component and its outbursts. The…
Our photometric observations of the symbiotic binary Z And during its recent (2000 -- 2003) active phase revealed a minimum in the U, B and V light curves (LC) at the position of the inferior conjunction of its cool component (the orbital…
Symbiotic binaries are comprised of nebulae, whose densest portions have electron concentrations of 1E+8 - 1E+12 cm-3 and extend to a few AU. They are optically thick enough to cause a measurable effect of the scattering of photons on free…
We present thermal-IR images of three extreme bipolar objects, M2-9, Mz3, and He2-104. They are bipolar planetary nebulae with bright central stars and are thought to be powered by symbiotic binary systems. The mid-IR images spatially…
A new set of low-resolution spectral and UBVJHKL-photometric observations of the symbiotic nova PU Vul is presented. The binary has been still evolving after the symbiotic nova outburst in 1977 and now it's in the nebular stage. It is found…
We present long-slit optical spectra along the major axis of the planetary nebula NGC 7009. These data allow us to discuss the physical, excitation and chemical properties of all the morphological components of the nebula, including its…
The results of a submillimetre wavelength spectral line survey between 455.1 -- 507.4 GHz of the Orion-KL hot cloud core are reported. A total of 254 lines were detected to a main beam brightness temperature sensitivity ~ 1 - 3 K. The…
High-resolution observations in the region, centered at 4400 \AA\ and those of the lines HeII 4686, Hbeta and HeI 6678 of the spectrum of the symbiotic binary Z And were performed during its outburst in 2006. The line Hbeta had additional…
Active phases of some symbiotic binaries survive for a long time from years to decades. The accretion process onto a white dwarf (WD) sustaining long-lasting activity, and sometimes leading to collimated ejection, is not well understood. We…
We present observations of the four hyperfine structure components of the OH 18 cm transition (1612, 1665, 1667 and 1720 MHz) toward a filamentary dark cloud, the Pipe nebula, with the Green Bank Telescope. A statistical equilibrium…
Ultracool stellar atmospheres show absorption by alkali resonance lines severely broadened by collisions with neutral perturbers. In the coolest and densest atmospheres, such as those of T dwarfs, Na I and K I broadened by molecular…
As part of a multi-wavelength campaign to observe the 2000--2002 outburst of the prototypical symbiotic star Z Andromedae, we observed this object six times each with the Multi-Element Radio Linked Interferometer Network (MERLIN) and Very…
AX Per is an eclipsing symbiotic binary. During active phases, deep narrow minima are observed in its light curve, and the ionization structure in the binary changes significantly. From 2007.5, AX Per entered a new active phase. It was…
Spectra of the bright symbiotic star AG Draconis (BD+67D922) in the wavelength range 905-1187 A obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) are presented. The spectra show a number of narrow, nebular emission lines,…
The spatial structure of the emission lines and continuum over the 50 arcsecond extent of the nearby, O-rich, planetary nebula NGC 7009 (Saturn Nebula) have been observed with the MUSE integral field spectrograph on the ESO Very Large…
Based on measurements with the Effelsberg 100-m telescope, a multi-line study of molecular species is presented toward the gravitational lens system PKS1830-211. Obtaining average radial velocities and performing Large Velocity Gradient…
High resolution FUSE and STIS observations of the bright QSO HE 0226-4110 (zem = 0.495) reveal the presence of a multi-phase absorption line system at zabs(O VI) = 0.20701 containing absorption from H I (Ly alpha to Ly theta), C III, O III,…
We analyze optical and ultraviolet observations of the symbiotic binary AG Pegasi acquired during 1992-97. The bolometric luminosity of the hot component declined by a factor of 2-3 from 1980-1985 to 1997. Since 1992, the effective…