26 citations · 44 across the 7 of their papers we have counts for
8 papers
Intra-night flickering of RS Ophiuchi: III. Modes of quasi-periods in the minute scale and their evolution
Ts. B. Georgiev, R. K. Zamanov, S. Boeva +7
We study the photometric behavior of the recurrent nova RS Oph by 58 monitoring light curves (LCs), taken by 5 telescopes. All LCs show repeating time structures with some quasi-pe…
Intra-night flickering of RS Ophiuchi: I. Sizes and cumulative energies of time structures
Ts. B. Georgiev, R. K. Zamanov, S. Boeva +7
We analyzed 29 pairs of time series in B and V bands of the recurrent nova RS Oph. The observations were carried out in 2008-2017 with duration 0.6 - 3.6 hours, with time resolutio…
Young stellar groups in M 33 galaxy: delineation and main parameters
Luba Vassileva, Todor Veltchev, Tsvetan Georgiev +1
The problem of (non-)existence of a typical size of the stellar associations is revisited by use of deep UBVRI stellar CCD photometry in M 33 from the Local Group Survey (Massey et…
The open cluster Berkeley 53
G. Maciejewski, B. Mihov, Ts. Georgiev
We present a photometric study of the neglected open cluster Berkeley 53. We derived its fundamental parameters, such as the age, the interstellar reddening, and the distance from…
Studying X-ray reprocessing and continuum variability in quasars: PG 1211+143
R. Bachev, D. Grupe, S. Boeva +5
We present the results from a monitoring campaign of the Narrow-Line Seyfert~1 galaxy PG 1211+143. The object was monitored with ground-based facilities (UBVRI photometry; from Feb…
Optical monitoring of the z=4.40 quasar Q 2203+292
E. P. Ovcharov, P. L. Nedialkov, A. T. Valcheva +5
We report Cousins R-band monitoring of the high-redshift (z=4.40) radio quiet quasar Q 2203+292 from May 1999 to October 2007. The quasar shows maximum peak-to-peak light curve amp…