A5005622906- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- SAS software applications and methods
- Solar and Space Plasma Dynamics
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Ionosphere and magnetosphere dynamics
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Molecular Spectroscopy and Structure
- Pulsars and Gravitational Waves Research
- Particle Detector Development and Performance
- Radio Astronomy Observations and Technology
- History and Developments in Astronomy
- Calibration and Measurement Techniques
- Neutrino Physics Research
- Analytical Chemistry and Sensors
- Atmospheric chemistry and aerosols
- Computational Physics and Python Applications
Special Astrophysical Observatory
2015-2023
Crimean Astrophysical Observatory
2004-2022
Bulgarian Academy of Sciences
2004
We present ground-based and HST optical observations of the transients (OTs) long-duration Gamma Ray Bursts (GRBs) 060729 090618, both at a redshift z = 0.54. For GRB 060729, bumps are seen in light curves (LCs), late-time broadband spectral energy distributions (SEDs) OT resemble those local type Ic supernovae (SNe). dense sampling our has allowed us to detect well-defined LCs, as well change colour, that indicative coming from core-collapse SN. The accompanying SNe for events individually...
ABSTRACT In 2021 BL Lacertae underwent an extraordinary activity phase, which was intensively followed by the Whole Earth Blazar Telescope (WEBT) Collaboration. We present WEBT optical data in BVRI bands acquired at 36 observatories around world. mid-2021 source showed its historical maximum, with R = 11.14. The light curves display many episodes of intraday variability, whose amplitude increases brightness, agreement a geometrical interpretation long-term flux behaviour. This is also...
ABSTRACT Among active galactic nuclei, blazars show extreme variability properties. We here investigate the case of BL Lac object S4 0954+65 with data acquired in 2019–2020 by Transiting Exoplanet Survey Satellite (TESS) and Whole Earth Blazar Telescope (WEBT) Collaboration. The 2-min cadence optical light curves provided TESS during three observing sectors nearly 1 month each allow us to study fast great detail. identify several characteristic short-term time-scales, ranging from a few...
We present results of imaging and aperture polarimetry the dust comet 2P/Encke at phase angles 91–105°, obtained during 2003 apparition. investigate how strongly molecular emissions transmitted by filters used in observations can affect resulting polarization cometary dust. This problem is particular importance for so-called gas-rich comets like which has particularly strong emission as compared to its continuum. Aperture wide-band UBVR was performed 2.6-m Shain telescope 1.25-m Crimean...
We present in this paper several high resolution () spectra of five UXORs (UX Ori, CQ Tau, BF RR WW Vul), which cover the entire visual range, from 3900 to about 8700 Å. There are between 4 and 7 per star, obtained over a time interval two years. Simultaneous or quasi-simultaneous photometric observations were also at Crimean Astrophysical Observatory. The complete, reduced normalized available electronic form. show for each star selection most interesting lines, full spectrum UX Ori...
We report measurements of linear and circular polarization for the recent comet C/2009 P1 (Garradd) during its approach to Earth in 2011–2012. Aperture photoelectric observations were carried out on July 29, 2011-April 22, 2012 R WR wide-band filters at 2.6-m telescope Crimean Astrophysical Observatory (Ukraine). Spectropolarimetric range 3800–8000 Å imaging polarimetry continuum filter (λ0 = 6840/90 Å) also with SCORPIO-2 focal reducer 6-m Special (Russia) February 2-April 21, 2012. The...
Abstract The results of photometric, spectral and radio studies the flare star EV Lac we obtained during course cooperative observations in 1994 1995 are presented. A quantitative analysis radiation emitted by two powerful flares using colour-colour diagram confirms previous conclusion on essential heterogeneity matter radiating optical flares. From simultaneous UBVRI, K H bands no significant brightness variations IR were found coincidence with observed small-amplitude flares, except a...
We present results of a multi-site photometric campaign on the high-amplitude $δ$\,Scuti star KIC\,6382916 in {\it Kepler} field. The was observed over 85-d interval at five different sites North America and Europe during 2011. photometry ground-based multicolour light curves are used to investigate pulsational content identify principal modes. High-dispersion spectroscopy also obtained order derive stellar parameters projected rotational velocity. From an analysis time series, three...
The star RZ Psc is one of the most unusual members UX Ori family. It demonstrates all properties that are typical these stars (the light variability, high linear polarization in deep minima, blueing effect), but until recently there has been no obvious evidence its youth. Recently, we have shown transitional evolutionary stage between with primordial and debris disks. In this paper present results quantitative analysis star’s spectrum. Using high-resolution (R = 46 000) spectrum obtained...
RZ Psc is an isolated high-latitude post-T Tauri star that demonstrates a UX Ori-type photometric activity. The shows very weak spectroscopic signatures of accretion, but at the same time possesses unusual footprints wind in Na i D lines. In present work we investigate new observations obtained 2014 during two observation runs. We found variable blueshifted absorption components (BACs) lines other alcali metals, K 7699 Å and Ca ii IR triplet. also confirmed presence emission component Hα...
We present results of polarimetric observations Saturn's moon Enceladus carried out from April 14, 2010 to 13, 2013 in WR spectral band (550-750 nm). used 2.6-m telescope equipped with a one-channel photoelectric photometer-polarimeter (Crimean Astrophysical Observatory). The measurements were performed at phase angles ranging 1.65° 5.71°. phase-angle dependence linear polarization was obtained using the our observations. Results are discussed terms existing models light scattering by...
Abstract A program of Many‐sites Multi Channel simultaneous observations flare stars by a network telescops was initiated in 1998. The purpose this is to investigate the fine structure flares light‐curve UBVRI, depressing atmospheric and instrumental noises. In paper we present results on Flare star EV Lac B color, which were carried out at Stephanion observatory during campaign 1999. Discrete Fourier Transform analysis B‐light curve largest reveal presence high frequency small amplitude...
Results of UBVRIJHKLM photometry, VRI polarimetry and optical spectroscopy a young star RW Aur A obtained during 2010-11 2014-16 dimming events are presented. During the second decreased its brightness to \Delta V > 4.5 mag, polarization light in I-band was up 30%, color-magnitude diagram similar that UX Ori type stars. We conclude reason both dimmings is an eclipses by dust screen, but size screen much larger than case UXORs.
ABSTRACT BP Psc is an active late-type (sp:G9) star with unclear evolutionary status lying at high-galactic latitude b = −57°. It also the source of well collimated bipolar jet. We present results proper motion and radial velocity study outflow based on archival Hα imaging GMOS camera 8.1-m Gemini-North telescope as recent long-slit spectroscopy SCORPIO multimode focal reducer 6-m BTA SAO RAS. The 3D kinematics jet revealed full spatial up to ∼140 km s−1 allows us estimate distance system D...