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1.
Churyumov K. I. Klesachonok V. V. Mussaev F. A. Bikmaev I. F. Galazutdinov G. H. 《Earth, Moon, and Planets》1997,78(1-3):105-110
We present the results of the preliminary study of the comet Hale-Bopp spectrum obtained April 17, 1997 by K. Churyumov and F. Mussayev with the help of the 1-meter Zeiss reflector and the echelle spectrometer (spectral resolutionλ/Δ λ ≈ 50000), CCD and the long slit, oriented along the radius-vector(“Sun-comet direction”). Energy distributions for three selected regions including the C3, C2 (0-0) and CN(Δ ν = 0) molecules emissions of the comet Hale-Bopp spectrum were built. The rotational lines of the CN(Δ ν = 0) band were identified. The nature of the high emission peak near λ 4020 Å in the C3 band is discussed. The presence of the cometary continuum of the nonsolar origin is assumed. 相似文献
2.
The results of a spectroscopic analysis of 15 stars that are photometric analogues of the Sun are reported. The effective temperatures and surface gravities in the stellar atmospheres are derived from published photometric indices and the HIPPARCOS parallaxes. The abundances of 33 elements ranging from lithium to europium are analyzed based on high-dispersion spectra taken with the new Coudé echelle spectrometer of the Terskol Observatory in the northern Caucasus. The main parameters of most of the stars agree with the data of an [Fe/H] catalog published in 2001. Our study of the chemical compositions of the sample stars indicates that photometric analogues of the Sun can be divided into three groups according to their elemental abundances: six stars have solar chemical composition, four have abundance excesses, and five have some abundance deficiencies. The sample contains two metal-deficient subgiants (HD 133002 and HD 225239). Our results demonstrate that photometric similarity is not a sufficient criterion to consider a star as solar analogue. When several criteria, including chemical composition, are simultaneously taken into account, only four stars from the sample can be considered true solar analogues: HD 10307, HD 34411, HD 146233 (18 Sco), and HD 186427 (16 Cyg B). These results confirm the previously published suggestion that 18 Sco is the most probable twin of the Sun: essentially all the parameters of the two stars coincide within the errors. 相似文献
3.
Bikmaev I. F. Irtuganov E. N. Nikolaeva E. A. Sakhibullin N. A. Gumerov R. I. Sklyanov A. S. Glushkov M. V. Khamitov I. M. Borisov V. D. Burenin R. A. Zaznobin I. A. Krivonos R. A. Lyapin A. R. Medvedev P. S. Meshcheryakov A. V. Sazonov S. Yu. Sunyaev R. A. Khorunzhev G. A. Gilfanov M. R. 《Astronomy Letters》2021,47(5):277-290
Astronomy Letters - Results of the spectroscopic observations at the 1.5-m Russian–Turkish telescope for another group of 12 X-ray sources discovered by the eROSITA telescope onboard the SRG... 相似文献
4.
Zaznobin I. A. Burenin R. A. Lyapin A. R. Khorunzhev G. A. Afanasiev V. L. Grokhovskaya A. A. Dodonov S. N. Eselevich M. V. Uklein R. I. Bikmaev I. F. Khamitov I. M. Gilfanov M. R. Lyskova N. S. Medvedev P. S. Sunyaev R. A. 《Astronomy Letters》2021,47(3):141-149
Astronomy Letters - We present the first results of our program of optical observations for galaxy clusters from the Lockman Hole X-ray survey with the eROSITA telescope onboard the SRG space... 相似文献
5.
We determine the atmospheric parameters of the secondary in the close binary system FF Aqr and analyze its chemical composition.
A series of high-resolution spectra are taken at different orbital phases using the coude echelle spectrometer of the 1.5-m
Russian-Turkish Telescope (RTT150). We show that the absorption line intensity of heavy elements varies with phase due to
the spotty nature of the cool component. We determine the abundances of heavy elements in the star’s atmosphere by modelling
the synthetic spectra and performing a differential analysis of the chemical composition of FF Aqr relative to the solar composition.
Our analysis of the averaged spectrum of FF Aqr yielded 539 abundance estimates for 21 chemical elements. We found the metallicity
of the star ([Fe/H] = −0.11 ± 0.08) to be close solar, in agreement with the hypothesis that FF Aqr should belong to the Galactic disk. The
inferred chemical composition of the objects exhibits no anomalous abundances of the α-, r-, and s-process elements like those earlier found in other systems (IN Com, LW Hya, V471 Tau). The lack of such anomalies in FF Aqr
must be due to the fact that the elements heavier than 16
O cannot be synthesized in the core of the primary during the last stages of its evolution. 相似文献
6.
R. Ya. Zhuchkov E. V. Malogolovets O. V. Kiyaeva V. V. Orlov I. F. Bikmaev Yu.Yu. Balega D. I. Safina 《Astronomy Reports》2010,54(12):1134-1149
An analysis of the physical characteristics, orbital parameters, and dynamical stability of the multiple Be star HD 217675
(o And) is presented. Observations on the 6-m SAO and 1.5-m RTT telescopes are used to refine the orbital parameters of the
subsystems. The spectral types, absolute magnitudes, and masses of the components are estimated. The total mass of the system
is 18 ± 2 M
db. It is shown that the configuration of the system is 2 + 2, where one of the subsystems is a spectral binary with a period
of 33 d and the outer pair has a period of 117 yr. The parameters of the second inner subsystem are uncertain, making it difficult
to draw firm conclusions about the stability of this multiple star. 相似文献
7.
8.
R. A. Burenin A. V. Mescheryakov M. G. Revnivtsev S. Yu. Sazonov I. F. Bikmaev M. N. Pavlinsky R. A. Sunyaev 《Astronomy Letters》2008,34(6):367-374
We present the results of our optical identifications of a set of X-ray sources from the INTEGRAL and SWIFT all-sky surveys. The optical data have been obtained with the 1.5-m Russian-Turkish Telescope (RTT-150). Nine X-ray sources have been identified with active galactic nuclei (AGNs). Two of them are located in the nearby spiral galaxies MCG-01-05-047 and NGC 973 seen almost edge-on. One source, IGR J16562-3301, is probably a BL Lac object (blazar). The remaining AGNs are observed as the starlike nuclei of spiral galaxies whose spectra exhibit broad emission lines. The relation between the hard X-ray (17–60 keV) luminosity and the [O III] 5007 line luminosity, log L x/L [O III] ≈ 2.1, holds good for most of the AGNs detected in hard X rays. However, the luminosities of some AGNs deviate from this relation. The fraction of such objects can reach ～20%. In particular, the [O III] line flux is lower for two nearby edge-on spiral galaxies. This can be explained by the effect of absorption in the galactic disks. 相似文献
9.
I. F. Bikmaev R. A. Burenin M. G. Revnivtsev S. Yu. Sazonov R. A. Sunyaev M. N. Pavlinsky N. A. Sakhibullin 《Astronomy Letters》2008,34(10):653-663
The results of optical identifications of five hard X-ray sources in the Galactic plane from the INTEGRAL all-sky survey are presented. The X-ray data on one source (IGR J20216+4359) are published for the first time. The optical observations were performed with the 1.5-m RTT-150 telescope (Turkish National Observatory, Antalya, Turkey) and the 6-m BTA telescope (Special Astrophysical Observatory, Nizhny Arkhyz, Russia). A blazar, three Seyfert galaxies, and a high-mass X-ray binary are among the identified sources. 相似文献
10.
Khamitov I. M. Bikmaev I. F. Burenin R. A. Glushkov M. V. Melnikov S. S. Lyapin A. R. 《Astronomy Letters》2020,46(1):1-11
Astronomy Letters - An example of simultaneous spectroscopic redshift measurements for a large number of galaxies in a cluster by multiobject spectroscopy with the medium- and low-resolution TFOSC... 相似文献