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1.
The testing and development of topological approaches to the analysis of solar magnetic fields are considered. A technique based on the geometry of random fields, mathematical morphology and topology, and scale-space analyses are applied to describe and diagnose the pre-flare dynamics of the magnetic fields of solar active regions using HMI/SDO magnetograms. The results show that this formalism can be used to diagnose pre-flare dynamics over time intervals that are of practical interest. 相似文献
2.
An experiment in mesocosms installed in a fish-rearing pond was used to adequately simulate the character of self-purification, migration, and the redistribution of cadmium and its chemical forms in major components of a freshwater ecosystem, into which this chemical is imported in concentrations far in excess of its MAC. The major portion of the imported cadmium was found to be removed from the water mass within a few days, mostly, as a component of particulate matter settling onto the bed, including dead plankton remains, as ion-exchange cadmium forms adsorbed by suspension (37%), and as forms associated with ferromanganese oxides (41%). The rate of cadmium removal from the water mass is determined both by the amount of particulate matter settling onto the bed and the efficiency of cadmium sorption by it, depending on the acid–alkaline and redox conditions in the water body. 相似文献
3.
I. Yu. Grigor’eva A. N. Shakhovskaya M. A. Livshits I. S. Knyazeva 《Astronomy Reports》2012,56(11):887-894
Solar filtergrams obtained at the Crimean Astrophysical Observatory at the center and wings of the H?? line are used to study variations in filaments, in particular, in arch filament systems (AFSs). These are considered as an indicator of emerging new magnetic flux, providing information about the spatial locations of magnetic-field elements. Magnetic-field maps for the active region NOAA 10030 are analyzed as an example. A method developed earlier for detecting elements of emerging flux using SOHO/MDI magnetograms indicates a close link between the increase in flare activity in theNOAA 10030 group during July 14?C18, 2002 and variations in the topological disconnectedness of the magnetograms. Moreover, variations in the flare activity one day before a flare event are correlated with variations in the topological complexity of the field (the Euler characteristic) in regions with high field strengths (more than 700 G). Analysis of multi-wavelength polarization observations on the RATAN-600 radio telescope during July 13?C17, 2002 indicate dominance of the radio emission above the central spot associated with the increase in flare activity. In addition to the flare site near the large spot in the group, numerous weak flares developed along an extended local neutral line, far from the central line of the large-scale field. The statistical characteristics of the magnetic-field maps analyzed were determined, and show flare activity of both types, i.e., localized in spot penumbras and above the neutral line of the field. 相似文献
4.
I. N. Glushneva A. V. Kharitonov I. B. Voloshina A. I. Zakharov L. N. Knyazeva V. M. Tereshchenko 《Astrophysics and Space Science》1989,152(2):313-317
TheSpectrophotometric Catalogue of the Sternberg State Astronomical Institute contains 875 stars; 8 of them are standards.TheCatalogue of the Fessenkov Astrophysical Institute consists of 1123 stars. The data on the spectral energy distribution for about a half of these stars are published.A comparison of energy distribution data for 473 common stars in the range 3200–7600 Å was made. Calibration of Alpha Lyr from Hayes (1985) was used for all the stars of both catalogues.In difference of the previous publications the comparison includes much more stars and energy distribution data were corrected where necessary. The agreement between the corrected data is better than in the case of the earlier comparison. Reductional factors due to the instrumental effects were taken into account for 275 stars from theSternberg Institute Catalogue. These factors are in the limits 1.01–1.04 and their mean value is 1.03.The reductional factors for the stars from theFessenkov Institute Catalague are much larger: 1.06–1.12 with the mean 1.06–1.07. In this case the reduction factors were taken into account for all the stars of the catalogue except the brightest ones withV<2.0.The values of the differences between spectral energy distribution data for common stars in dependence of magnitude, spectral type, and wavelength are presented. 相似文献
5.
Geomagnetism and Aeronomy - Solar flare prediction remains an important practical task of space weather. An increase in the amount and quality of observational data and the development of... 相似文献
6.
A topological method for detecting the new emergence of magnetic flux using SOHO/MDI magnetograms of the full solar disk is
proposed. This method uses the number of pixels in the image that can be distinguished from a specified value to within a
predetermined threshold (the number of disconnected components). We study more than ten very powerful active regions (ARs)
with very high flare activity and show that the number of disconnected components increases directly before the development
of a series of M and X flares, or accompanies this process. This behaviour is evident not only when there is an explicit emergence
of a new flux and a series of fast flares, such as in AR 9236 (November 2000), but also in groups with many non-stationary
processes developing along a neutral line of the large-scale magnetic field. We also discuss the possibility of using the
obtained results for flare prediction. 相似文献
7.
Themain purpose of this paper is to describe the evolution of the magnetic field of active regions of the Sun in the context of Minkowski functionals: the Euler characteristic and perimeter calculated on the excursion set for a specified level. Themethods of geometry of random fields was applied to the MDI SOHO magnetogram, containing flaring active regions. The results demonstrated that morphological functional tracked the dynamic scenarios of the magnetic fields preceded by flares or accompanying them. 相似文献
8.
We have derived the normal spectral energy distributions for those early-type subgiants, giants, and supergiants that were not investigated in our earlier studies, which were in most cases also not included in the studies of Sviderskiene. Color indices computed using our normal energy distributions are in good agreement with normal colors derived from observations in the Vilnius photometric system. The reliability of our distribution curves is also demonstrated by comparisons of observed and computed (W-B)-(B-V) two-color diagrams in the WBVR system. Normal color indices for the photometric WBVR system are derived. 相似文献
9.
The color indices of the Sun in the u vby system are calculated using the spectral energy distribution of Lockwood, Tug, and White. This allows errors in the absolute calibration to be excluded from the calculated color indices. The normal position of the Sun on the (v-b)?(b-y) and (v-y)?(b-y) color-color diagrams for early G stars testifies to the absence of any significant peculiarities in the Sun compared to other stars of similar spectral type. These diagrams can provide a useful tool in searches for candidate solar analogues among faint stars. 相似文献
10.
Geomagnetism and Aeronomy - The Maunder butterfly pattern is the most complete spatial-temporal representation of observed changes in solar activity in the 11-year cycle over a period of... 相似文献