Zobrazeno 1 - 10
of 11
pro vyhledávání: '"Stefanov, S."'
Autor:
Stoyanov, K. A., Luna, G. J. M., Zamanov, R. K., Ilkiewicz, K., Nikolov, Y. M., Moyseev, M., Minev, M., Kurtenkov, A., Stefanov, S. Y.
T CrB is a symbiotic star that experiences nova outbursts every $\sim$ 80~yr. The next, long-anticipated nova outburst should occur during the 2024-2026 period. Here, we present results of high-resolution optical spectroscopy of T CrB in the period 2
Externí odkaz:
http://arxiv.org/abs/2406.01971
Autor:
Zamanov, R. K., Stoyanov, K. A., Marchev, V., Minev, M., Marchev, D., Moyseev, M., Marti, J., Bode, M. F., Konstantinova-Antova, R., Stefanov, S.
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 the 2.0m RCC telecope of the Rozhen National Astronomical Observatory
Externí odkaz:
http://arxiv.org/abs/2405.11506
Publikováno v:
Bulgarian Astronomical Journal, 38, 68 (2023)
We analyzed TESS photometric data of the flickering-active cataclysmic star AQ Men in 2018--2019. We processed 7 sectors with 14 light curves (LCs) inside them, with a time resolution of 2 min. Aiming to study the "macro-flickering", with quasi perio
Externí odkaz:
http://arxiv.org/abs/2312.08982
The Be stars display variable optical emission lines originating in the circumstellar disc. Here we analyse high resolution spectroscopic observations of Be stars and the distance between the peaks of H-alpha, H-beta, and H-gamma emission lines ($\De
Externí odkaz:
http://arxiv.org/abs/2302.11975
We present a detailed photometric study of the bright cataclysmic variable BG Tri using ground-based observations mainly from Rozhen Observatory, ASAS-SN, TESS, and WASP sky surveys. We report the discovery of a negative superhump with P$_{-sh}$ = 0.
Externí odkaz:
http://arxiv.org/abs/2208.10855
Autor:
Zamanov, R. K., Stoyanov, K. A., Marchev, D., Tomov, N. A., Wolter, U., Bode, M. F., Nikolov, Y. M., Stefanov, S. Y., Kurtenkov, A., Latev, G. Y.
We present new spectroscopic observations of the Be/black hole binary MWC 656 obtained during the period 2015 - 2021. We measure the equivalent width of H$\alpha$ (EW$_\alpha$), H$\beta$ ($EW_\beta$), and the distance between the peaks of H$\alpha$ (
Externí odkaz:
http://arxiv.org/abs/2206.06013
We report spectroscopic observations of the $H\alpha$ emission line of the recurrent nova RS~Oph obtained between 12 and 23 August 2021 during the recent outburst. On the basis of the sharp P~Cyg profile superimposed onto the strong H-alpha emission,
Externí odkaz:
http://arxiv.org/abs/2109.11306
Autor:
Stefanov, S. Y.
$TESS$ photometric data of LS~Cam from sectors 19, 20 and 26 are analysed. The obtained power spectra from sectors 19 and 20 show multiple periodicities - orbital variations ($P_{orb} = 0.14237$ days), slightly fluctuating superorbital variation ($ P
Externí odkaz:
http://arxiv.org/abs/2106.03568
The success of chemotharapy in soft matter as a survival is found in the paper. Therefore, it is found the analogous tumor stretching force in soft matter; ultrasonography is performed for this tumor; restoration in soft matter with such a tumor is f
Externí odkaz:
http://arxiv.org/abs/1404.0936
Autor:
Stefanov, S. Z.
The expected path of an open system,which is a big Poincare system,has been found in this paper.This path has been obtained from the actual and from the expected droop of the open system.The actual droop has been reconstructed from the variations in
Externí odkaz:
http://arxiv.org/abs/cs/0603070