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We present the results of our photometric (V RI) and spectroscopic observations of the young variable star V730 Cep (MisV1147) classified by Uemura et al. (2004) as a Herbig Be star. Our photometry confirms the conclusion of the above authors that this star has a complex pattern of variability including periodic or quasi-periodic brightness variations with a period of about 14 days and deep Algol-like minima typical for UX Ori stars. Our spectroscopy shows that the classification of V730 Cep as a Herbig Be star is wrong. Actually, this star has a much lower temperature and belongs to the family of T Tauri stars. This allows us to explain the nature of the unusual photometric activity of V730 Cep based on a combination of two well-known models of variable circumstellar extinction applied to young stars: AA Tau- and UX Oritype variability. It follows from our observations that the color tracks on the V ?(V ?I) color–magnitude diagram for these models slightly differ: the AA Tau-type variability of circumstellar extinction is caused by larger grains than the UX Ori-type variability. Such a difference can be due to an increase in the characteristic sizes of circumstellar dust as the star is approached and has a simple explanation: small dust grains evaporate faster than large ones. 相似文献
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A. A. Kucheiko A. Yu. Ivanov A. A. Davydov A. Yu. Antonyuk 《Izvestiya Atmospheric and Oceanic Physics》2016,52(9):1031-1040
This paper is devoted to the detection and identification of icebergs in the Russian Arctic Seas from the use of high- and medium-resolution radar and optical images from EROS-B, Radarsat-1, Radarsat-2, SPOT-4 and SPOT-5 Earth observation satellites. In July–September of 2011–2013, the SCANEX Research and Development Center, the Federal State Unitary Enterprise Atomflot, and other partner organizations provided operational satellite monitoring of icebergs in the Kara Sea and the Laptev Sea. More than 130 highly detailed optical and radar images were received and processed. The Vilkitsky Strait—one of the narrowest and most dangerous places within the Northern Sea Route—was chosen as an experimental polygon. As a result, iceberg location in the strait during the 2011–2013 navigation periods was analyzed, as were the iceberg size, area, drift direction, and height. 相似文献
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S. V. Zaitsev N. N. Kiselev V. K. Rosenbush S. V. Kolesnikov K. A. Antonyuk 《Kinematics and Physics of Celestial Bodies》2014,30(3):155-160
Results of polarimetric observations of a high-albedo asteroid 64 Angelina obtained in the phase-angle range from 0.8° to 24.3° are presented. The observations were carried out in the period from September 28 to October 9, 2008, and on November 15, 2011, and September 18, 2012, with the 1.25-m and 2.6-m telescopes of the Crimean Astrophysical Observatory equipped with a five-color double-beam photopolarimeter and a single-channel photometer-polarimeter, respectively. Our observations confirm the polarimetric opposition effect in asteroid 64 Angelina at small phase angles and well agree with the other observations. The obtained results are discussed in terms of the currently available models of the light scattering by regolith surfaces. 相似文献
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Five color UBVRI photometric and polarimetric measurements of the eclipsing binary VW Cyg are reported. It is shown that in the primary minimum the luminosity is attenuated (at short wavelengths) even after passage of the second contact. This fact is interpreted as evidence of gaseous structures in the system. The exchange of matter among the system components is also confirmed by the O-C curve constructed from data covering nearly a hundred years. Polarimetric analysis makes it possible to isolate the intrinsic (P=0.030±0.02) and interstellar components of the polarization. The UBVRI light curves of VW Cyg have been resolved. This was done using an algorithm for synthesizing theoretical light curves in the Roche model. Good agreement was obtained between the theoretical curves and observations in the V, R, and I bands, but the observed minimum depths in the U and B bands exceed the theoretical values. This appears to be caused by gas flows in the system. 相似文献
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Pavlenko E. P. Sosnovskii A. A. Antonyuk K. A. Antonyuk O. I. Pit’ N. V. Kokhirova G. I. Rakhmatullaeva F. J. Baklanov A. V. 《Astrophysics》2021,64(3):293-305
Astrophysics - Photometric studies of the type SU UMa dwarf nova NY Her were made during 2017 and 2020 at the Crimean Astrophysical Observatory and at the Sanglokh Observatory over a total of 77... 相似文献
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A. F. Valeev K. A. Antonyuk N. V. Pit A. S. Moskvitin A. O. Grauzhanina D. R. Gadelshin S. V. Kolesnikov E. A. Zhuzhulina T. E. Burlakova G. A. Galazutdinov A. G. Gutaev R. Ya. Zhuchkov A. I. Ikhsanova D. G. Zhukov Arti Joshi J. C. Pandey A. F. Kholtygin G. G. Valyavin 《Astrophysical Bulletin》2017,72(1):44-50
We report the results of photometric observations of a number of magnetic white dwarfs in order to search for photometric variability in these stars. These V-band observations revealed significant variability in the classical highly magnetized white dwarf GRW+70?8247 with a likely period from several days to several dozen days and a half-amplitude of about 0. m 04. Our observations also revealed the variability of the well-known white dwarf GD229. The half amplitude of its photometric variability is equal to about 0. m 005, and the likely period of this degenerate star lies in the 10–20 day interval. This variability is most likely due to the rotation of the stars considered.We also discuss the peculiarities of the photometric variability in a number of other white dwarfs. We present the updated “magnetic field–rotation period” diagram for the white dwarfs. 相似文献
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K. A. Antonyuk 《Bulletin of the Crimean Astrophysical Observatory》2009,105(1):56-59
We present results of multicolor photometric and polarimetric observations of the binary system V1696 CYG obtained in the Crimean Astrophysical Observatory in 2006. It is shown that observed variations of the linear polarization of the V1696 Cyg light are well correlated with the orbital period phase. We also found brightness variations (～0.1 m ) in the UBVRI bands. The brightness variations are weakly correlated with the orbital period phase. A rapid photometric variability was found. 相似文献
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