Detailed surface photometry of NGC 2685, a galaxy with polar ring     

V. V. Makarov  V. P. Reshetnikov  V. A. Yakovleva 《Astrophysics》1989,30(1):6-14

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The clustering of luminous red galaxies in the Sloan Digital Sky Survey imaging data     

Nikhil Padmanabhan  David J. Schlegel  Uro&#; Seljak  Alexey Makarov  Neta A. Bahcall  Michael R. Blanton  Jonathan Brinkmann  Daniel J. Eisenstein  Douglas P. Finkbeiner  James E. Gunn  David W. Hogg  &#;eljko Ivezi&#;  Gillian R. Knapp  Jon Loveday  Robert H. Lupton  Robert C. Nichol  Donald P. Schneider  Michael A. Strauss  Max Tegmark  Donald G. York 《Monthly notices of the Royal Astronomical Society》2007,378(3):852-872

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IGU Commission on Changing Rural Systems Subcominission on Highlands and High-Latitude Zones     

V. I. Makarov  K. R. Sivaraman 《GeoJournal》1989,18(3):327-327

The International Geographical Union Reports

IGU Commission on Changing Rural Systems Subcominission on Highlands and High-Latitude Zones  相似文献   

Does the Poleward Migration Rate of the Magnetic Fields Depend on the Strength of the Solar Cycle?     

Makarov  V.I.  Tlatov  A.G.  Sivaraman  K.R. 《Solar physics》2001,202(1):11-26

We present the pattern of the polar magnetic reversal for cycle 23 derived from H synoptic charts and have also included the reversals of the earlier cycles 18–22 for comparison. At the beginning of a new cycle (i.e., soon after the polar reversal) the zonal boundaries of unipolar magnetic regions of opposite polarities (seen as filament bands on the synoptic charts) appear close to and on either side of the equator continuing through the years of minimum indicating the onset of the cancellation of flux at these low latitudes. The cycle thus starts with cancellation of flux close to the equator and ends with the polar reversal or flux cancellation near the poles. The filament bands just below the polemost ones migrate and reach latitudes 35°–45° by the time of polar reversal and become the polemost, once the polar reversal has taken place. During the years of minimum that follow, these filament bands remain more or less stagnant at the latitudes 35°–45° except for occasional slow migration towards the equator. The migration to the poles starts at a low speed of 3 m s^–1 only when the spot activity has risen to a significant level and then it accelerates to 30 m s^–1 at the peak of the activity. It takes 3–4 years for the polemost bands to reach the poles moving at these high speeds. We quantify this possible cause and effect phenomenon by introducing the concept of the `strength of the solar cycle' and represent this by either of a set of three parameters. We show that the velocity of poleward migration is a linear function of the `strength of the solar cycle'.  相似文献   

Polar magnetic field reversals of the Sun in Maunder Minimum     

V. I. Makarov  A. G. Tlatov 《Journal of Astrophysics and Astronomy》2000,21(3-4):193-196

A possible scenario of polar magnetic field reversal of the Sun during the Maunder Minimum (1645–1715) is discussed using data of magnetic field reversals of the Sun for 1880–1991 and the¹⁴ C content variations in the bi-annual rings of the pine-trees in 1600–1730 yrs.  相似文献   

A moving group of young stars in Carina–Vela     

Valeri V. Makarov  Sean Urban 《Monthly notices of the Royal Astronomical Society》2000,317(2):289-298

Accurate two-colour photometry and proper motions of 7096 young X-ray stars in the ROSAT All-Sky Survey Bright Star Catalogue, version 1RXS, are extracted from the Tycho-2 Catalogue. The sample is dominated by red main-sequence and possibly pre-main-sequence stars. On a global proper motion convergence map, two features are very prominent: the nearby section of the Gould Belt and the Hyades convergent point. The appearance of the Gould Belt feature with its peak at ( l =2443, b =−126) is quite similar to that of Hipparcos OB stars. When only stars with proper motions drawing close to that point are selected, strong concentrations of stars in the direction of the Sco–Cen complex are found. Another concentration, not corresponding to any known OB association, is detected between the position of the Lower Centaurus Crux and Vela OB2 associations. It is a new young moving group located in Carina and Vela, and a near extension of the Sco–Cen complex. Contrary to the classical Gould Belt OB associations, the Carina–Vela moving group has a considerable geometric depth, the closest members being as near as 30 pc from the Sun. IC 2391, one of the youngest and closest open clusters on the sky, is a part of the Carina–Vela moving group. The Carina–Vela moving group does not link the Sco–Cen complex with the Vela OB associations, because the latter is much more distant than the outer limit of the sample. It is more likely that the young late-type population of the Scorpio–Centaurus–Carina moving group stretches towards the Sun and possibly beyond it.  相似文献   

Alluvium: Implications for stratigraphy and correlation of quaternary sediments     

N. V. Makarova  V. I. Makarov  G. A. Postolenko  B. E. Akinin 《Stratigraphy and Geological Correlation》2011,19(4):450-471

Based on a generalized knowledge of conditions and mechanisms for accumulation of the cycle terrace alluvium on plain and mountain rivers, alluvium is suggested as an instrument for stratigraphic studies, interregional correlation, and correction of present schemes. Diachronous alluvial formations are uniformly constructed. They include two subunits, a lower “warm” and an upper “cool” one. In addition the formations are subdivided in dynamic phases that display a dominating regime and stages of erosion-and-accumulation cycle. Alluvial formations are characterized by a peculiar mechanical and mineralogical composition, gradation, bedding, thickness, landscape and climatic conditions of accumulation, paleontological content, character of occurrence, and position in a cycle incision. All these characters of an alluvial formation and its subformations correspond to a complete climatic rhythm and oscillation stages. Alluvial formations are associated in a certain way with glacial and marine sediments making up a single formation complex.  相似文献   

Large-Scale Magnetic Field and Sunspot Cycles     

Makarov  V.I.  Tlatov  A.G.  CALLEBaUT  D.K.  Obridko  V.N.  Shelting  B.D. 《Solar physics》2001,198(2):409-421

Hα magnetic synoptic charts of the Sun are processed for 1915–1999 and the spherical harmonics are calculated. It is shown that the polarity distribution of the magnetic field on Hα charts is similar to the polarity distribution of the Stanford magnetic field observations during 1975–1999. The index of activity of the large-scale magnetic field A(t), representing the sum of the intensities of dipole and octupole components, is introduced. It is shown that the cycle of the large-scale magnetic field of the Sun precedes on the average by 5.5 years the sunspot activity cycle, W(t). This means that the weak large-scale magnetic fields of the Sun do not result from decay and diffusion of strong fields from active regions as it is supposed in all modern theories of the solar cycle. On the basis of the new data the intensity of the current solar cycle 23 is predicted and some aspects of the theory of the solar cycle are discussed.  相似文献   

Modeling the Star Population of Resolved Galaxies     

D. I. Makarov  L. N. Makarova 《Astrophysics》2004,47(2):229-241

A program is developed for determining the history of star-forming galaxies based on the use of two- or multicolor photometry of the resolved stars in a given galaxy. We create a library of synthetic color-magnitude diagrams from theoretical stellar isochrones, taking the initial mass function, distance to the galaxy, internal and external absorption, and photometric errors into account. The resulting synthetic diagrams are combined linearly and compared quantitatively with photometric data for stars in a galaxy in order to determine star formation rates as a function of age and metallicity. This program is tested in detail under different conditions using artificial color-magnitude diagrams. Special attention is given to the limiting case when only the brightest stars of a galaxy can be seen in the color-magnitude diagram and the number of resolved stars is at most a few hundred. This limiting case corresponds to a large fraction of the nearby galaxies at distances of 3-5 Mpc observed by large ground based telescopes and the Hubble Space Telescope.  相似文献   

Magnetic waves of solar activity     

V. I. Makarov  A. A. Ruzmaikin  S. V. Starchenko 《Solar physics》1987,111(2):267-277

An asymptotic solution of generation equations for the solar mean magnetic field is given and studied. The variation of rotational angular velocity with depth is taken from helioseismological data. Average helicity is prescribed according to the mixing length theory. It is shown that three dynamo waves of the magnetic field are excited. The first wave is generated at the surface layer and concentrates at latitudes of about 60°. Its activity becomes apparent in the poleward migration of the zone of polar faculae formation. The second more powerful wave of the field is excited in the center of the convection zone and its activity shows up in a sunspot cycle. The third wave which is similar to the first wave, is generated at the bottom of the convection zone and attenuates towards the surface. Its activity may appear as a three-fold reversal of the polar magnetic field.  相似文献