Natural resource potential of northern regions: methodological characteristics of comprehensive assessment

The economic assessment of renewable natural resources remains a relevant and as yet unresolved problem. Today, the economic assessment of natural resources is viewed as one of the priority tasks in the state strategy for environmental management. To a large extent, such economic assessment has become relevant following the development of market relations in Russia that require the valuation of natural resource potential. In Russia, the state cadastral appraisal of natural resources, which is already continuing for a second decade, serves as the basis to calculate the land tax for individual categories of land and does not allow making a comprehensive assessment of natural resource potential. This article expands the concept of economic assessment, describes the practice of its implementation in northern regions. It examines the traditional methodological approaches to economic assessment that are used today, such as the cost approach and its modi cations, rental income approach, market approach, alternative approach, as well as the methodological approaches based on the results of sociological studies, which have become more widespread recently. The recommendations put forward by the authors with regard to the economic assessment provide for consistency in its implementation based on a results-driven approach that ensures the comparability of calculations and improves the reliability of obtained results. The methodological approaches proposed for assessing the land, forest, hunting, fishery and biological resources of wild plants allow considering the specific characteristics of northern territories and implementing a comprehensive economic assessment of the region’s natural resource potential. The authors consider the expediency of calculating the unit value index of natural resource potential in order to rank the areas within the subject of the Russian Federation in proportion to the investment in the projects aimed at developing the natural resources. The methodological recommendations have been tested in the context of Berezovsky municipal district of Khanty-Mansi Autonomous Area—Yugra.The article has been prepared with the support of the Grant No. 14–18–00456 Substantiating the Geo-Eco-Socio-Economic Approach to the Development of Strategic Natural Resource Potential of Northern Understudied Territories as Part of the Investment Project The Arctic—Central Asia provided by the Russian Science Foundation

Correlation function of spin noise due to atomic diffusion

We use paramagnetic Faraday rotation to study spin noise spectrum from unpolarized Rb vapor in a tightly focused probe beam in the presence of N$_2$ buffer gas. We derive an analytical form for the diffusion component of the spin noise time-correlation function in a Gaussian probe beam. We also obtain analytical forms for the frequency spectrum of the spin noise in the limit of a tightly focused or a collimated Gaussian beam in the presence of diffusion. In particular, we find that in a tightly focused probe beam the spectral lineshape can be independent of the buffer gas pressure. Experimentally, we find good agreement between the calculated and measured spin noise spectra for N$_2$ gas pressures ranging from 56 to 820 torr.Comment: 6 pages, 4 figure

Dimer-atom scattering between two identical fermions and a third particle

We use the diagrammatic $T$-matrix approach to analyze the three-body scattering problem between two identical fermions and a third particle (which could be a different species of fermion or a boson). We calculate the s-wave dimer-atom scattering length for all mass ratios, and our results exactly match the results of Petrov. In particular, we list the exact dimer-atom scattering lengths for all available two-species Fermi-Fermi and Bose-Fermi mixtures. In addition, unlike that of the equal-mass particles case where the three-body scattering $T$-matrix decays monotonically as a function of the outgoing momentum, we show that, after an initial rapid drop, this function changes sign and becomes negative at large momenta and then decays slowly to zero when the mass ratio of the fermions to the third particle is higher than a critical value (around 6.5). As the mass ratio gets higher, modulations of the $T$-matrix become more apparent with multiple sign changes, related to the "fall of a particle to the center" phenomenon and to the emergence of three-body Efimov bound states.Comment: 6 pages, 3 figures, and 2 table