174 research outputs found

    Ferromagnetic Detectors of Axions in RF (S - X) Band

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    The (pseudo) Goldstone bosons arise naturally in many modern theories such as supergravity, superstring theory and variants of general relativity with torsion. By the other hand, there are well known indications that a large part of the Universe mass exists in a form of dark matter. The most attractive model of the dark matter is non-relativistic gas of the light elementary particles weakly interacting with the "usual" matter \cite{b2} - \cite{b4}. We describe ferromagnetic detectors, for search of arion(axion), where a high-sensitive two-channel SHF receiver is used. Its sensitivity reaches to 10βˆ’20 Wt10^{-20}\,Wt, with time of accumulation 1βˆ’10 s1-10\,s. Fourier analysis of signal provides a survey in zone up to Β±50 KHz\pm50\,KHz with spectral resolution 0.1βˆ’25 Hz0.1 - 25\, Hz. There was applied a high sensitive SHF receiver based on a special computer method of coherent accumulation of signals. It is possible to use the receiver in other precise experiments: measuring of electron/positron beams polarization in storage rings, investigation of parity violation, investigation of atmosphere with radars etc.Comment: 6 pages, LaTeX, no figure

    The relevance of the contemporary landscape-ecological and biogeochemical studies of the Ob floodplain

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    We have systematized and summarized the results of the Ob River floodplain studies and have shown that the flood and the floodplain influence all the territory of Western Siberia due to the processes happening there. The floodplain at different times was the object of interest of many scientists, but the total level of study of the Ob and the associated ground and the lake network water resources and quality can be generally assessed as low. The waters of the Ob middle course are quite polluted according to bacteria content. It is possible that a significant part oforganic and biogenic substances, microorganisms and some microelements come into the Ob floodplain waters from anthropogenic and natural sources distributed in the watersheds area. The soils of the Ob Riverfloodplain can be considered to be clean andfree ofany chemical pollution. In these soils, the amount of trace elements is small. To study the floodplain changes after a flood the methods of landscape ecology are used, such as the collection and analysis of stock and descriptive materials, literature and maps; the preparation of a series of component and general landscape maps. Nowadays a complex research of the Ob River and the adjacent surface waters is relevant

    Investigation of the earth roof through the combined method: mechanical way and ground penetrating radar in the Yamalo-Nenets Autonomous Okrug

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    The paper presents the results of the multidisciplinary experimental investigation of the soils in the sporadic permafrost Northern-taiga subzone (Yamalo-Nenets Autonomous Okrug, Western Siberia) based on the combination of the methods of radiophysical GPR investigation and classical methods of soil science. The aim is to develop the methods of objective identification of soils during the decoding of radarograms when monitoring the state of permafrost soil

    Study of the process e+eβˆ’β†’ppΛ‰e^+e^-\to p\bar{p} in the c.m. energy range from threshold to 2 GeV with the CMD-3 detector

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    Using a data sample of 6.8 pbβˆ’1^{-1} collected with the CMD-3 detector at the VEPP-2000 e+eβˆ’e^+e^- collider we select about 2700 events of the e+eβˆ’β†’ppΛ‰e^+e^- \to p\bar{p} process and measure its cross section at 12 energy ponts with about 6\% systematic uncertainty. From the angular distribution of produced nucleons we obtain the ratio ∣GE/GM∣=1.49Β±0.23Β±0.30|G_{E}/G_{M}| = 1.49 \pm 0.23 \pm 0.30

    Pilot studies of the unique highland palsa mire in Western Sayan (Tuva Republic, Russian Federation)

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    In contrast to the well-studied West Siberian sector of frozen bogs in the Russian Arctic, the frozen mound bogs (so-called β€œpalsas”) on the highlands of Southern Siberia have not yet been studied, but they are suspected to be even more sensitive to ongoing climate change. This article provides the pilot study on palsa mire Kara-Sug in the highland areas of Western Sayan mountain system, Tuva Republic. The study focuses on the current state of palsa mire and surrounding landscapes, providing wide range of ecological characteristics while describing ongoing transformations of natural landscapes under a changing climate. The study used a variety of field and laboratory methods: the integrated landscape-ecological approach, the study of peat deposits, geobotanical analysis, and modern analysis of the chemical composition of water, peat, and soils. The study shows that highland palsa mires are distinguished by their compactness and high variety of cryogenic landforms leading to high floristic and ecosystem diversity compared with lowland palsa mires. This information brings new insights and contributes to a better understanding of extrazonal highland palsa mires, which remain a β€œwhite spot” in the global environmental sciences

    Seasonal dynamics of organic carbon and metals in thermokarst lakes from the discontinuous permafrost zone of western Siberia

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    Despite relatively good knowledge of the biogeochemistry of Siberian thermokarst lakes during summer base flow, their seasonal dynamics remains almost unexplored. This work describes the chemical composition of 130 thermokarst lakes ranging in size from a few m2 to several km2, located in the discontinuous permafrost zone. Lakes were sampled during spring flood, just after the ice break (early June), the end of summer (August), the beginning of ice formation (October) and during the full freezing season in winter (February). The lakes larger than 1000m2 did not exhibit any statistically significant control of the lake size on dissolved organic carbon (DOC), the major and trace element concentrations over three major open water seasons. On the annual scale, the majority of dissolved elements including organic carbon increased their concentration from 30 to 500 %, with a statistically significant (p summer>autumn>winter. The ice formation in October included several stages: first, surface layer freezing followed by crack (fissure) formation with unfrozen water from the deeper layers spreading over the ice surface. This water was subsequently frozen and formed layered ice rich in organic matter. As a result, the DOC and metal (Mn, Fe, Ni, Cu, Zn, As, Ba and Pb) concentrations were highest near the surface of the ice column (0 to 20 cm) and decreased by a factor of 2 towards the bottom. The main implications of discovered freeze-driven solute concentrations in thermokarst lake waters are enhanced colloidal coagulation and removal of dissolved organic matter and associated insoluble metals from the water column to the sediments. The measured distribution coefficients of a TE between amorphous organo-ferric coagulates and lake water (<0.45 ΞΌm) were similar to those reported earlier for Fe-rich colloids and low molecular weight (<1 kDa, or <1–2 nm) fractions of thermokarst lake waters, suggesting massive coprecipitation of TE with amorphous Fe oxyhydroxide stabilized by organic matter. Although the concentration of most elements was lowest in spring, this period of maximal water coverage of land created a significant reservoir of DOC and soluble metals in the water column that can be easily mobilized to the hydrological network. The highest DOC concentration observed in the smallest (<100m2) water bodies in spring suggests their strongly heterotrophic status and, therefore, a potentially elevated CO2 flux from the lake surface to the atmosphere
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