Publications
Section: PZ: main journal
New Eclipsing Variable Star with Delta Scuti Component We present our discovery a new variable star USNO-A2.0 1350-17086180 from observations at the Astrotel-Caucasus Observatory. The object shows Algol-type eclipses and, simultaneously, low-amplitude, short-period pulsations.
Novae in the 80th Name-list of Variable Stars (Part 3): Official Announcement of GCVS Names GCVS names are announced for 14 galactic Novae discovered in late 2011--early 2013.
Two Transiting Exoplanet Candidates in Cygnus from the MASTER Project We present two transiting exoplanet candidates in Cygnus discovered during a small photometric survey performed at the Kourovka Astronomical Observatory of Ural Federal University in the summer of 2012. The MASTER-1 b candidate (host star 2MASS 20260213+5006032, R=12.4) has a period of 0.847d, transit depth of 0.015m, and transit duration of 1.6h. The MASTER-2 b candidate (host star 2MASS 20341625+5015427, R=13.8) has a period of 0.983d, transit depth of 0.017m, and transit duration of 1.7h. We believe that these transit-like signals might be caused by Hot Jupiters. Observations, data reduction, transit search tools, and detected candidates are described. Follow-up photometric and spectroscopic observations are needed to clarify the nature of the candidates.
GSC 1374-01131, a High-Amplitude Delta Scuti Star with an Eclipsing Component I present the discovery of an eclipsing component in light variations of the known High-Amplitude Delta Scuti star GSC 1374-01131 based on the Catalina Surveys publicly available data.
Photometric Observations and Preliminary Modeling of Type IIb Supernova 2011dh CCD UBVRI photometry is presented for type IIb SN 2011dh for about 300 days. The main photometric parameters are derived and the comparison with SNe of similar types is reported. The light curves are similar to those for SN IIb 2008ax, but the initial flash is stronger and very short, and there are humps on the light curves in U and B at the onset of linear decline. Preliminary modeling is carried out, and the results are compared to the quasi-bolometric light curve and to the light curves in UBVRI bands.
Spectroscopic Evidence for Appearance of a New Decretion Disk Around IGR J06074+2205 We report on a new episode of decretion disk formation in the IGR J06074+2205 system. Our spectroscopic data permit us to measure peak separation in the double-peaked H-alpha line as 408+/-55 km/s and hence to determine the disk radius as 1.6 star's radii. These findings permit us to predict possible new X-ray activity of IGR J06074+2205 in the nearest future.
New Variables in Pegasus: How Can We Use WASP0 Data In the course of our work on the 80th Name-List of Variable Stars, we encountered a field in Pegasus with about 70 variable stars announced as new discoveries from the WASP0 survey. Our analysis shows that the amount of wrong information published for these stars is unacceptably large. We present correct information on WASP0 variables, both those that still remain unstudied by other authors and those with reliable studies in the literature. Our new information is based on publicly available sky surveys. We also discuss requirements to presentation of data on new variable stars that permit to include information into variable-star catalogs without a too large amount of extra work for catalog compilers.
A Study of the Cataclysmic Variable 1RXS J174320.1-042953 We report on our photometric analysis of the poorly studied cataclysmic variable in Ophiuchus, 1RXS J174320.1-042953 (DDE 11). The results of the monitoring with the Bradford Robotic Telescope (BRT) are presented, as well as the time-resolved photometry obtained at the Montecatini Astronomical Centre. The long-term behavior of J1743-0429 shows that it is a probable magnetic cataclysmic variable (polar), with a large difference between its low and high states. The orbital period obtained from our observations is 0.0866 d, or 2.08 h, close to the lower boundary of the period gap of cataclysmic variables.
The Spectrum of the Optical Transient in NGC 5775 On 2012 April 25, we acquired spectra and images of NGC 5775 OT PSN J14535395+0334049, classified as a calcium transient similar to NGC 300 OT and SN 2008S in NGC 6496. The Russian 6-m telescope and the SCORPIO focal reducer were used. The spectral range was 4070 - 5830 A and the spectral resolution, 5.4 A. The spectrum is noisy and shows a continuum with an H_{beta} emission line. The line has a two-component profile containing a narrow component, with FWHM ~ 300 km/s, and a broad one, with FWHM ~ 4000 km/s. The object is located at the front of the edge-on galaxy disk, it is weakly reddened. We estimate its M_V as -13.7m on the date of observation, typical of a calcium-type supernova impostor.
Photometric Activity of the Herbig Ae star WW Vul Photometric CCD observations of the pre-main-sequence Herbig Ae star WW Vul on separate nights during 2007-2011 are presented. The star exhibited long-term non-periodic variability in the range of 0.8 mag; rapid variations with a small amplitude were superimposed. The results of a search for periodicity in the light variations are reported. |