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Article
The chemical composition of the atmospheres, the masses, radii, and other parameters of four Am stars
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Article
Thorium abundance in the atmospheres of Am stars
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Article
Determination of the uranium abundance in the Ap star 73 Dra using the line U II λ 3859.58
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Article
Element abundances in the atmosphere of the chemically peculiar star β Cr B
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Article
Possible presence of magnetic fields and iron content of atmospheres of “Metallic” Am-stars
Measurements with a CCD camera were made of two Fell lines at λ=6747.7 Å and 6149.2 Å in the spectra of 12 Am stars. The greater line strength of Fell λ 6147.7 Å relative to that of λ 6149.2 Å can be taken as .....
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Article
Magnetic fields and the abundance of iron at the surface of late-type dwarfs
A program package developed for implementation of the Stenflo-Lindegren method for investigation of magnetic fields with complex structure is described. It has been used to carry out magnetic field diagnostics...
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Article
The "F str 4077" star HD 177645 as a possible barium dwarf star
The abundances of 12 elements in the atmosphere of the "F str 4077" star HD 177645 have been determined from new spectroscopic observations with the CCD camera and the model atmosphere method. The overabundanc...
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Article
Vertical Chromium Distribution in the Atmosphere of a Chemically Peculiar Star. I. Diagnostics
On the basis of CCD spectrograms obtained with high resolution at the Coudé focus of the 2.6-m telescope of the Crimean Astrophysical Observatory, Cr II lines lying in the wings of the Hβ hydrogen line are inv...
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Article
Vertical Chromium Distribution in the Atmospheres of CP Stars. II. Modeling
Vertical chromium distributions in the atmospheres of several Ap and Am stars are fitted using detailed modeling of the profiles of CrII lines. The vertical distributions obtained for Ap stars are consistent w...
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Article
Brightness Variability of 12 ROTD A-Stars
The brightness variability of 12 stars of spectral class A which are type ROTD objects is analyzed. The power spectra of these objects contain characteristic features including a amplitude-dominant narrow peak...
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Article
Areas, Lifetimes, and Magnetic Fields of Starspots
The results of applying a method developed by us for determining the spottedness parameter A to data on the brightness variation of 34030 objects based on observations with the Kepler space telescope are prese...
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Article
Activity of the Star ET Dra
V-band photometric observations of the FK Com type star ET Dra were made at the Zvenigorod observatory (INASAN) during March-April 2018. The new data were used in a solution of the inverse problem of recoverin...
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Article
Activity of the Star bScl Observed by the TESS Space Telescope
The rotational and flare activity of the chemically peculiar star B9.5IIIpHgMnSi βScl is studied using data from the archive of the TESS space mission. Rotational modulation of the brightness is clearly visibl...
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Article
The Program Magreg for Determining the Longitudinal Component of Stellar Magnetic Fields from Spectropolarimetric Observations
The computer program magreg in IDL language has been developed for determining the longitudinal component Bz of the magnetic field of stars. The program has been tested on observations of a number of objects a...
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Article
Slowly Rotating Ap Stars, Prospects for Observing Them with the Tess Space Mission
The feasibility of detecting candidate slow-rotating magnetic Ap stars with periods from a few tens of days to several hundred years is considered. The question of the fraction of objects of this kind among al...
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Article
Differential Rotation of Stars in Spectral Class A
Published data indicate a substantial increase in the differential rotation parameter ∆Ω of stars hotter than 6700 K. By analyzing the shape of the light curves and the presence of a specific set of peaks in t...
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Article
KIC 7732964 – A Possible Candidate FK Com-Type Star
This article is a brief survey of our previous work devoted to searching for candidate type FK Com giant stars and an analysis of data for yet another new candidate, KIC 7732964. Establishing that KIC 7732964 ...
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Article
Activity of Two Young Stars of Solar Type with Planetary Systems from the Ursa Major Moving Group of Stars and the Stream Psc-Eri
High precision data from the archive of the TESS space mission are used as the basis of a study of the photometric variability of two young analogs of the Sun with planetary systems: the stars HD 63433 (TOI 17...
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Article
Spottedness Activity of the Young Star TOI 1227 with a Planetary System from Lower Centaurus Crux OB Association (Musca)
Based on high-precision data from the archive of the TESS space mission, a study of the photometric variability of the brightness of TOI 1227, a young member of the Musca group with an age of 11 million years....
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Article
Activity of Stars with Planets in the Habitable Zone
Based on data on stars with planets located in the habitable zone, a study is made of manifestations of their activity. Light curves obtained during observations in the Q3 set with the Kepler Space Telescope f...