2 citations · 5 across the 10 of their papers we have counts for
10 papers
H_alpha observations of the Be/X-ray binary MWC 656
R. Zamanov, V. Marchev, K. A. Stoyanov +8
Context. MWC 656 is a Be/X-ray binary identified as an emission-line object, X-ray and radio source and might be a weak gamma-ray source, harbouring an enigmatic secondary componen…
Red giant component of the recurrent nova T Coronae Borealis
R. K. Zamanov, D. Marchev, V. Marchev +5
We performed simultaneous V band photometry and spectroscopic observations of the recurrent nova T CrB and estimate the V band magnitude of the red giant. We find for the red giant…
Interstellar extinction toward MWC 148
R. Zamanov, I. Stateva, J. Marti +2
We analyse high resolution optical spectra of MWC148 (optical counterpart of the gamma-ray source HESS J0632+057) obtained at Observatoire de Haute Provence and Rozhen Observatory.…
Size of the accretion disc in the recurrent nova T CrB
R. K. Zamanov, K. A. Stoyanov, V. Marchev +7
We present high resolution (0.06 A/px) spectroscopic observations of the recurrent nova T Coronae Borealis obtained during the last 1.5 years (September 2022 -- January 2024), with…
Luminosity class of the symbiotic stars 4U1954+319 and ZZ CMi
R. Zamanov, K. A. Stoyanov, G. Latev +8
We performed optical photometry and spectral observations of the symbiotic stars 4U1954+319 and ZZ CMi. For 4U1954+319 using high-resolution spectra we measure the equivalent width…
Accretion in the recurrent nova T CrB: Linking the superactive state to the predicted outburst
R. Zamanov, S. Boeva, G. Y. Latev +6
Context: T CrB (NOVA CrB 1946) is a famous recurrent nova with a recurrence timescale of 80 years. Aims: We aim to estimate the colours, luminosity, and mass-accretion rate for T C…
Mass accretion rate in the jet-driving symbiotic binary MWC 560
V. Marchev, R. Zamanov
We analyze photometric observations of the symbiotic star MWC 560 in B and V bands obtained during the period 1990-2023. We estimate the luminosity and the mass accretion rate of t…
Pre-outburst signal in the light curves of the recurrent novae RS Oph and T CrB
R. K. Zamanov, V. Marchev, J. Marti +1
Pre-outburst signal (a decrease of the optical brightness) just before the outburst is clearly detected in the observations of the T CrB obtained before and during the 1946 outburs…
The hidden symbiotic star SU Lyn -- detection of flickering in U band
R. K. Zamanov, A. Kostov, M. Moyseev +18
We report photometric observations of the hidden symbiotic star SU Lyn in the optical bands. In five nights we detect a weak flickering in U band with amplitude of about 0.05 magni…
Interstellar extinction toward symbiotic stars
R. K. Zamanov, V. D. Marchev, K. A. Stoyanov
Using diffuse interstellar bands (DIBs) at 5780 A, 5797 A and 6613 A, visible in the high resolution spectra, and measuring their equivalent widths, we estimate the interstellar ex…