X-ray line formation in the spectrum of SS 433

The mechanisms for the formation of X-ray lines in the spectrum of SS 433 are investigated by taking into account the radiative transfer inside the jets. The results ofMonte Carlo numerical simulations are presented. The effect of a decrease in line intensity due to scattering inside the jet turns out to be pronounced, but it does not exceed 60% in magnitude on the entire grid of parameters. The line broadening due to scattering, nutational motion, and the contribution of satellites can lead to overestimates of the jet opening angle ?? from the line widths in Chandra X-ray observations. The fine structure of the lines turns out to be very sensitive to the scattering effects. This makes its investigation by planned X-ray observatories equipped with high-resolution spectrometers (primarily Astro-H) a powerful tool for diagnosing the parameters of the jets in SS 433.     

Isotope composition and magma sources of the Kresty volcanopluton in Polar Siberia

The first data are presented on the distribution of rare elements and isotope composition of neodymium and strontium in the rocks of the alkaline-ultramafitic association of the Kresty volcanoplutonic structure (one of the probable satellites of the Gulinian massif being the largest in the Maimecha-Kotui alkaline province in Polar Siberia). On the basis of the results of geochemical studies performed and formerly obtained geophysical and isotope data, a new model is proposed for the plume nature of magmatism in the region, based on the action of a single mantle source of the PREMA type and its active interaction with the matter of the Earth’s crust.     

Hydrological hazards in Russia: origin,classification, changes and risk assessment

Hydrological extreme events pose an imminent risk to society and economics. In this paper, various aspects of hydrological hazards in Russia are analysed at different scales of risk assessment. It is shown that the number of hydrological and meteorological hazards in Russia has been growing every year. The frequency of economic losses associated with extreme low flow in this century has increased by factor five compared to the last decade of the previous century. With regard to floods, an interesting spatial patter can be observed. On the one hand, the number of floods in the Asian part of the country has increased, whereas on the other hand, the number and intensity of floods in estuarine areas in the European part of Russia have significantly reduced since the middle of the twentieth century, especially in the 2000s. This decrease can be attributed to runoff flooding in the mouths of regulated rivers, with an effective system of flood and ice jam protection. The analysis shows that there is an 8–12-year periodicity in the number of flood occurrences and that flood surges have intensified over the last 110 years, especially on the European territory of Russia. An integrated index that accounts for flood hazards and socio-economic vulnerability was calculated for each region of Russia. A classification of flood risk was also developed, taking into account more than 20 hydrological and social–economic characteristics. Based on these characteristics, hazard and vulnerability maps for entire Russia were generated which can be used for water management and the development of future water resources plans.

     

Optical identification of the source IGR J08390-4833 from the INTEGRAL all-sky survey

Results of the optical identification of the hard X-ray source IGR J08390-4833 recently discovered in the INTEGRAL all-sky survey are presented. We show that the source is most likely a cataclysmic variable, i.e., an accreting white dwarf in a binary. Analysis of its optical light curve clearly reveals intrinsic variability on timescales of the order of an hour or longer. However, the short time of the source’s optical observations does not allow a definitive conclusion about the periodicity of the detected variability to be reached. Further optical and X-ray observations are required for a more accurate classification of the source.     

Dangerous ice phenomena on the lowland rivers of European Russia

In the Russian climate, the security of populations and economic security are often limited by dangerous ice phenomena. Not only ice-jam floods, but also some processes lead to the violation of operating conditions of various facilities (water intakes, roads, bridges) and damage hydraulic structures and shipping. Currently, rivers’ ice regime characteristics change under the influence of both natural (primarily climatic) and anthropogenic factors. Changes have been analyzed in detail on the basis of observations of 300 hydrological stations in the period from 1936 to 2013. Changes of ice phenomena hazards have been estimated. Hazard assessment of flooding caused by ice jams has been carried out for the Northern Dvina River reach from the Velikiy Ustyug City to Kotlas, the most problematic ice jam flooding area in European Russia. The modeling was performed on the basis of STREAM_2D software complex for current conditions and taking into account the possible construction of various protective structures. Methods for the prevention of negative impact of water at the site are examined.

     

Polychronity and polygeneity of pegmamtites of gneissic-amphibolitic complexes as a result of continuous-discontinuous development of suture zones: Example of the Ufalei metamorphic block in the Middle Urals

In suture zones of the Urals, geological and physical-chemical conditions for formation of large ore and nonmetalliferous deposits existed during each geodynamical environment of development of the Urals. The development was predetermined by the duration and discontinuous-continuous existence of these structures, and the latter promoted the development of polygenetic and polychronic pegmatites of various types (by depth and productivity) and other postmagmatites. It has been shown in the example of the Ufalei metamorphic block that pegmatites of different ages (from R₂ to P) are often spatially combined. In this paper, two age diagrams are presented: the first one is for geological events that took place in the Ufalei metamorphic block; the second one is for Vendian pegmatites in it. The value of this paper is determined by the fact that the data obtained in Ufalei block could be used for study of postmagmatites within its analogs, which are gneissic-amphibolitic complexes of the Northern Urals, and especially by the fact that the project “Polar Urals, Industrial Urals” is implemented there.     

Localization of the solar flare SF900610 in X-rays with the WATCH instrument of the GRANAT observatory

During the solar flare of June 10, 1990, the WATCH instrument of the GRANAT space observatory obtained 110 localizations of the X-ray source in the X-ray range 8–20 keV. Its coordinates were measured with an accuracy of ～2 arcmin at a 3σ confidence level. The coordinates of the X-ray source do not coincide with the coordinates of the Hα-line flare. The X-ray source moved over the solar disk during the flare. This probably implies that, as the X-ray emission was generated, different parts of one loop or a system of magnetic loops dominated at different flare times.