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41.
Belikov V. T. Kozlova I. A. Ryvkin D. G. Yurkov A. K. 《Izvestiya Physics of the Solid Earth》2020,56(3):425-436
Izvestiya, Physics of the Solid Earth - Laboratory experiments on monitoring the acoustic emission signals and time variations of volumetric activity of radon during uniaxial loading of a granite... 相似文献
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Basilevsky A. T. Michael G. G. Krasilnikov S. S. Kozlova N. A. 《Solar System Research》2020,54(5):361-371
Solar System Research - The paper discusses three types of processes of destruction of small lunar craters: (1) destruction by overlapping craters; (2) destruction due to filling with ejecta from... 相似文献
43.
The results of a non-LTE analysis of a number of spectral lines formed in the accreting envelopes of UX Ori stars are given. The accretion rate is estimated from an analysis of the first three lines of the Balmer series: M a = 10?8 ?10?9 M ⊙ The gas temperature in this region is about 10,000 K. In the immediate vicinity of the star there is a hotter region, with T > 15,000 K, in which the 5876 Å line of neutral helium, observed in the spectra of these stars, is formed. The region of formation of this line has a small geometrical thickness, covers a small fraction of the star’s visible disk, and evidently consists of the site of contact of the accreting gas with the stellar surface. The low gas rotation rates in this region (150–200 km/sec) may mean that rapid rotation of the accreting gas is damped by the star’s magnetic field, which is strong enough to affect the gas stream. We estimate the magnetic field strength in this region to be about 150 G. 相似文献
44.
Results of spectral observations of the isolated Ae Herbig star CQ Tau obtained in 1995–1998 in the Hα line and near the sodium resonance doublet are presented, together with simultaneous photometric monitoring of the star. CQ Tau is a member of the family of young UX Ori stars with nonperiodic Algol-like brightness decreases. The star is surrounded by an accretion disk, in which its emission-line spectrum and part of its absorption-line spectrum are formed. The strong variability of the Hα, D NaI, and HeI 5876 Å lines testifies that the gaseous disk is appreciably inhomogeneous in both the radial and azimuthal directions. This inhomogeneity probably results from uneven feeding by the circumstellar material from the peripheral regions of the circumstellar disk. Over the four years of observations, we observed the star in deep minima three times (ΔV~2). On these nights, an increase in the Hα equivalent width followed the decrease in radiation flux. In the two deepest minima, the normally two-component line profile had only a single component with a nearly symmetrical profile. This behavior of the Hα line is in good agreement with the results of numerical modeling of Algol-like minima and can be used to estimate the parameters of the dust clouds eclipsing the star and inner accretion disk. These estimates suggest that the circumstellar dust clouds can approach very close to the star and be sublimated there. 相似文献
45.
R. R. Gabdullin A. V. Ivanov E. A. Shcherbinina O. V. Zerkal’ E. N. Samarin A. A. Gatina G. K. Kozlova E. A. Koshkina D. V. Nadezhkin 《Moscow University Geology Bulletin》2011,66(6):393-403
In this work, based on the example of a well drilled in the valley of the Mzymta River (Northwest Caucasus) the possibilities
of the sequence-stratigraphic method are demonstrated for the first time. This method allows us to clarify the natures of
numerous repetitions in the same interval of the geological sequence (modern, ancient landslide or syn-sedimentary-landslide,
and tectonic or eustatic). In addition, the geochemical characteristics of bituminous sediments are given. The sequence that
was studied in the well shows the complex polygenetic evolution of sediments since Aptian time and the oceanic anoxic event-1. 相似文献
46.
Pogodin M. A. Pavlovskii S. E. Beskrovnaya N. G. Drake N. A. Kozlova O. V. Alekseev I. Yu. Fenandes M. Borges Pereira C. B. Valyavin G. G. Miroshnichenko A. S. Gorda S Yu. Gorshanov D. L. 《Astrophysics》2022,65(1):31-52
Astrophysics - Results are presented from a spectroscopic study of the Ae/Be Herbig star HD 259431 conducted from 2010 to 2019 using high-resolution spectrographs at: (a) the Crimean Astrophysical... 相似文献
47.
We present long-term spectral observations (R = 20000) of IN Com in the region of the Hα, Hβ, and He I 5876 lines. One distinguishing characteristic of the stellar spectrum is the presence in the Hα line of an extended two-component emission with limits up to ±400 km/s. Emission parameters show the rotation modulation with the stellar rotation period and a significant variability on the long-term scale. Similar emissions are also observed in the Hβ and He I 5876 lines. Our results allow us to conclude that observational emission profiles are formed in an optically thin hot gas. This is a result of the presence of a circumstellar gas disk around IN Com. Its size does not exceed several stellar radii. The material for the disk is supported by the stellar wind from IN Com. The detected variability of Hα-emission parameters shows a clear connection with the photopolarimetric activity of the star. This fact allows us to associate the long-term spectral variability with cycles of stellar activity of IN Com. 相似文献
48.
The activity of the variable star IN Com is considered using the latest multicolor UBVRI photometry and linear polarimetric observations carried out during a decade. The photometric variability of the star is fully described using the zonal spottedness model developed at the Crimean Astrophysical Observatory (CrAO). Spotted regions cover up to 22% of the total stellar surface, with the difference in temperatures between the quiet photosphere and the spot umbra being 600 K. The spots are located at middle and low latitudes (40°–55°). The intrinsic broad-band linear polarization of IN Com and its rotational modulation in the U band due to local magnetic fields at the most spotted (active) stellar longitudes were detected for the first time. 相似文献
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