The behaviour of prominence areas in the 11-Year cycle and their relationship with other solar events     

M. N. Gnevyshev  V. I. Makarov 《Solar physics》1985,95(1):189-192

On the basis of the data on prominence areas for 1880–1976 and positions of the boundary background magnetic field for 1955–1982 it is shown that the maximum development of prominences and their poleward migration, accompanied by the magnetic field reversal, concides with the first maximum of the 11-year solar cycle, which is characterized by an enhancement of solar activity at all latitudes. The second maximum is an increase of all features, including prominences but in the low latitudes only. That prominence zone migrates poleward in the following 11-year solar cycle.  相似文献   

Chaos and Wavefront Reversal for Long-Range Sound Propagation     

Makarov  D. V.  Komissarov  A. A. 《Doklady Earth Sciences》2022,507(2):1118-1123

Doklady Earth Sciences - Long-range sound propagation in the deep ocean is considered. Attention is concentrated on the procedure of acoustic wavefield refocusing by means of the wavefront...  相似文献   

Ultra-flat galaxies selected from RFGC catalog. I. The sample properties     

V. E. Karachentseva  Yu. N. Kudrya  I. D. Karachentsev  D. I. Makarov  O. V. Melnyk 《Astrophysical Bulletin》2016,71(1):1-13

We used the Revised Flat Galaxy Catalog (RFGC) to create a sample of ultra-flat galaxies (UFG) covering the whole northern and southern sky apart from theMilkyWay zone. It contains 817 spiral galaxies seen edge-on, selected into theUFG sample according to their apparent axial ratios (a/b)_B ≥ 10.0 and (a/b)_R ≥ 8.53 in the blue and red bands, respectively. Within this basic sample we fixed an exemplary sample of 441 UFG galaxies having the radial velocities of V_LG < 10000 km s^?1, Galactic latitude of | b |> 10° and the blue angular diameter of a_B > 1.′0. According to the Schmidt test the exemplary sample of 441 galaxies is characterized by about (80–90)% completeness, what is quite enough to study different properties of the ultra-flat galaxies. We found that more than 3/4 of UFGs have the morphological types within the narrow range of T = 7± 1, i.e. the thinnest stellar disks occur among the Scd, Sd, and Sdm types. The average surface brightness of UFG galaxies tends to diminish towards the flattest bulge-less galaxies. Regularly shaped disks without signs of asymmetrymake up about 2/3 both among all the RFGC galaxies, and the UFG sample objects. About 60% of ultra-flat galaxies can be referred to dynamically isolated objects, while 30% of them probably belong to the scattered associations (filaments, walls), and only about 10% of them are dynamically dominating galaxies with respect to their neighbours.  相似文献   

Radar scattering on gravity-capillary waves: Laboratory investigation     

S. A. Ermakov  E. V. Makarov  I. A. Sergievskaya 《Izvestiya Atmospheric and Oceanic Physics》2007,43(2):243-249

The mechanism of the resonance (Bragg) scattering of microwaves by gravity-capillary waves (GCWs) is checked experimentally. Resonant regularities of backscattered signal intensity are obtained as functions of frequency and GCW propagation direction. It is shown that the width of the resonance curves is determined by the width of the directivity pattern of the scatterometer’s antenna. The excitation of the GCW second harmonic and the spatial structure of the wave field at the GCW doubled frequency are investigated. The ratio of the amplitudes of the free wave and forced harmonic that originated during excitation of the primary wave is determined. The resonance curve is obtained for the second-order scattering of radio waves (on forced harmonics and free GCWs). The correction to the backscattering cross section is investigated in the second order of smallness relative to the Bragg term.  相似文献   

LONG-TERM VARIATIONS OF THE TORSIONAL OSCILLATIONS OF THE SUN     

Makarov  Valentine I.  Tlatov  Andrey G.  Callebaut  Dirk K. 《Solar physics》1997,170(2):373-388

We investigated long-term variations of the differential rotation of the solar large-scale magnetic field on 1024 H charts in the latitude zones from +45° to -45° in the period 1915–1990. We used the expansion in terms of Walsh functions. It turns out that the rotation of the Sun becomes more rigid than average during the cycle maximum and the rotation is more differential during minimum. From 1915 to 1990, 7 bands of faster- and 7 bands of slower-than-average rotation are revealed showing an 11-year period. These bands drift towards the equator: 45° in 2.5 to 8 years. The time span of the bands varies from 4 to 6.8 years and is in anti-phase with long-term solar activity. The latitude span of the bands of torsional oscillations varies from 0.5 R to 1.3 R and shows a long-term variation of about 55 years. The poloidal component of velocity, V varies from 2 ms ^-1 to 6 ms ^-1. The maximum rate of the equatorial drift occurs in the period between 1935 and 1955 and it develops prior to the highest maximum activity. At the modern epoch from 1965 to 1985, V does not exceed 3 ms ^-1, but now it has a tendency to increase. The bands of slower-than-average rotation correspond to the evolution of the magnetic activity towards the equator in the butterfly diagram.  相似文献   

New results concerning the global solar cycle     

V. I. Makarov  K. R. Sivaraman 《Solar physics》1989,123(2):367-380

We derive the poleward migration trajectory diagram of the filament bands for the years 1915–1982 from the H-alpha synoptic charts. We find that the global solar activity commences soon after the polar field reversal in the form of two components in each hemisphere. The first component we identify with the polar faculae that appear at latitudes 40–70° and migrate polewards. The second and the more powerful component representing the sunspots shows up at 40° latitudes 5–6 years later and drifts equatorward giving rise to the butterfly diagram. Thus the global solar activity is described by the faculae and the sunspots that occur at different latitude belts and displaced in time by 5–6 years. This gives rise to the prolonged duration for the global solar activity lasting for 16–18 years as against the 11 years which has come about based only on the spots. The two components match with the pattern of the coronal emission in 5303 Å line. Finally, we show that the two components of activity also match with the pattern of excess shear associated with the torsional oscillations on the Sun and this provides a link between the torsional oscillations and the magnetic activity.  相似文献   

Seismotectonic deformations and recent tectonics of the Tien Shan     

N. A. Sycheva  S. L. Yunga  L. M. Bogomolov  V. I. Makarov 《Izvestiya Physics of the Solid Earth》2008,44(5):351-363

Seismotectonic strains (STSs) are calculated on the basis of the catalog of focal mechanisms of earthquakes including more than 5000 events compiled at the Institute of Seismology, National Academy of Sciences of the Kyrgyz Republic, in order to investigate deformation processes in the Tien Shan (38°–44°N, 68°–80°E). A modern approach to STS classification based on the identification of 11 deformation settings (including four main, two extreme, and five transitional settings) is applied for constructing STS maps. Areal distributions of the Lode-Nadai coefficient, vertical component, and angle of the stress-state type are obtained. The results of the calculations are verified by comparing them with STS calculations using focal mechanisms of 116 strong earthquakes from the centroid moment tensor catalog of Harvard University that occurred in the studied region in 1976–2003.  相似文献   

Parameter Variations in the Subsoil Radon Field at the Paratunka Station of the Petropavlovsk-Kamchatsky Geodynamic Test Site in 2011–2016     

P.?P.?FirstovEmail author  E.?O.?Makarov  I.?P.?Glukhova 《Seismic Instruments》2018,54(2):121-133

A network of stations for subsoil radon monitoring is in operation at the Petropavlovsk-Kamchatsky geodynamic testing area and is aimed at detection of strong earthquake precursors. At all stations, measurements are carried out using gas-discharge counters located at different depths within aeration zones of soft sediments. The volume activity of radon (VA Rn) is monitored at the most equipped station Paratunka (PRT) at three measurement sites located across the regional fault. The radon flux density (RFD) is measured from the surface. The article reviews responses in the dynamics of VA Rn and RFD from the surface at the PRT station prior to the Kamchatka earthquakes with magnitudes М _W > 5 that occurred over the period of 2011–2016. The revealed RFD seasonal cycle is likely related to the seasonal variations in air temperature. The postseismic effect caused by the strongest deep Okhotsk earthquake (May 24, 2013, М _W = 8.3) is detected in the RFD data. The behavior of VA Rn dynamics during time periods of the strong earthquakes is different. The results confirm the existing opinion on the formation of narrowly localized zones of Rn runoff to the atmosphere owing to both vertical and horizontal irregularities in the top layer of soil, which can react differently to changes in the geoenvironment stress–strain. On the basis of the real-time radon monitoring data, the authors have issued partially successful short-term prediction for several earthquakes. The results of this work confirm the opinion of many researchers that radon monitoring can be used in the short-term prediction of strong earthquakes.  相似文献   

A study of heat transport at the ice base and structure of the under-ice water layer in Southern Baikal     

I. A. Aslamov  V. V. Kozlov  G. B. Kirillin  I. B. Mizandrontsev  K. M. Kucher  M. M. Makarov  N. G. Granin 《Water Resources》2017,44(3):428-441

Experimental data and a new model of ice buildup are used to assess and to study variations of heat flux at the water–ice interface. The latter plays an important part in ice cover formation but still is poorly known because of the lack of field temperature measurements with sufficient spatial and temporal resolution along the phase transition boundary, which knowledge gap is filled by this study.  相似文献   

Sea Level Fluctuations as a Key Factor in Delta Formation     

Bolshiyanov  D. Yu.  Makarov  A. S. 《Water Resources》2022,49(5):781-795

Water Resources - Based on studies of the geological and geomorphological structure of the mouth areas of the Ob, Pyasina, Khatanga, and Lena rivers, a model for delta development as a result of...  相似文献