52 citations · 222 across the 18 of their papers we have counts for
18 papers
Mass outflow from the symbiotic binary RS Oph during its 2021 outburst
N. A. Tomov, M. T. Tomova, K. A. Stoyanov +7
RS Oph is a symbiotic recurrent nova containing a massive white dwarf with heavy mass loss during activity. In August 2021, it underwent its seventh optical eruption since the end…
The symbiotic binary ZZ CMi: intranight variability and suggested outbursting nature
R. K. Zamanov, K. A. Stoyanov, A. Kostov +9
We present photometric and spectral observations of the symbiotic star ZZ CMi. We detect intranight variability - flickering and smooth variations in U band. The amplitude of the f…
An eccentric wave in the circumstellar disc of the Be/X-ray binary X Persei
R. K. Zamanov, K. A. Stoyanov, U. Wolter +7
We present spectroscopic observations of the Be/X-ray binary X Per obtained during the period December 2017 - January 2020 (MJD~58095 - MJD~58865). In December 2017 the , ,…
A collimated wind interpretation for the spectral variability of Z And during its major 2006 eruption
N. A. Tomov, M. T. Tomova, D. V. Bisikalo
High-resolution observations in the region, centered at 4400 Å and those of the lines HeII 4686, Hbeta and HeI 6678 of the spectrum of the symbiotic binary Z And were performed dur…
Transient accretion disc-like envelope in the symbiotic binary BF Cygni during its 2006 - 2015 optical outburst
N. A. Tomov, M. T. Tomova, D. V. Bisikalo
The optical light of the symbiotic binary BF Cygni during its last eruption after 2006 shows orbital variations because of an eclipse of the outbursting compact object. The first o…
Orbital parameters of the high-mass X-ray binary 4U 2206+54
K. A. Stoyanov, R. K. Zamanov, G. Y. Latev +2
We present new radial velocities of the high-mass X-ray binary star 4U 2206+54 based on optical spectra obtained with the Coude spectrograph at the 2m RCC telescope at the Rozhen N…