排序方式： 共有26条查询结果，搜索用时 15 毫秒
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S. E. Pavlovskiy M. A. Pogodin V. V. Kupriyanov D. L. Gorshanov 《Astronomy Letters》2015,41(6):289-298
We present new results of our photometry for the Herbig Be star HD 52721 obtained from January 16 to March 25, 2013. A new data reduction technique is used. Using this technique, we have also reanalyzed the previous results of our photometry for this object pertaining to the period from March 7 to March 28, 2010. The Be star HD 52721 is known as an eclipsing variable with the period P = 1d. 610. Two photometric minima observed during one period are a peculiarity of its photometric variability. They are separated in phase of the period P by 0.5 and differ from one another in depth by 0 m . 04. We have also detected additional minima observed at the phases of maximum brightness. We hypothesize that they can be associated with the existence of local azimuthal inhomogeneities rotating synchronously with the orbital motion of the binary component stars in the circumstellar envelope. When processing our CCD frames, we have applied an efficient CCD-frame rejection method that has allowed the accuracy of observations to be increased considerably. The CCD frames have been further processed using the Apex II software package, which is a universal software platform for astronomical image processing. We justify the need for additional photometric observations of HD 52721 in various color bands to confirm the hypothesis about the existence of azimuthal inhomogeneities in the program binary system and to analyze their physical properties. 相似文献
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M. T. Botticella A. Pastorello S. J. Smartt W. P. S. Meikle S. Benetti R. Kotak E. Cappellaro R. M. Crockett S. Mattila M. Sereno F. Patat D. Tsvetkov J. Th. Van Loon D. Abraham I. Agnoletto R. Arbour C. Benn G. Di Rico N. Elias-Rosa D. L. Gorshanov A. Harutyunyan D. Hunter V. Lorenzi F. P. Keenan K. Maguire J. Mendez M. Mobberley H. Navasardyan C. Ries V. Stanishev S. Taubenberger C. Trundle M. Turatto I. M. Volkov 《Monthly notices of the Royal Astronomical Society》2009,398(3):1041-1068
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Gorshanov D. L. Devyatkin A. V. Ivanov A. V. Naumov K. N. Petrova S. N. Rusov S. A. L’vov V. N. Tsekmeister S. D. 《Solar System Research》2020,54(1):34-43
Solar System Research - The asteroid (13553) Masaakikoyama was observed with the ZA-320M and MTM-500M telescopes of the Pulkovo observatory in August and September 2018. Its axial rotation period... 相似文献
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A. A. Kisselev Yu. N. Gnedin E. A. Grosheva N. A. Shakht D. L. Gorshanov M. Yu. Piotrovich 《Astronomy Reports》2007,51(2):100-108
We have used two astrometric methods developed at the Main Astronomical Observatory of the Russian Academy of Sciences—the method of apparent-motion parameters (AMP) and a direct geometrical method (DGM)—to derive the orbit of the star S2 around the Galactic center, and thereby the mass of the supermassive black hole at the Galactic center. The AMP method, which is based on measurements of the curvature of a fairly short orbital arc, is efficient if observational data on the relative radial velocity are available. The mass of the supermassive black hole was also estimated using astrophysical methods, based on the empirical relation between the masses of the supermassive black holes at the centers of galaxies and quasars and the radio and X-ray luminosities of these regions. We estimate the magnetic-field strength near the event horizon of the supermassive black hole at the Galactic center using a synchrotron self-absorption model. 相似文献
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