Comment on "Clock Shift in High Field Magnetic Resonance of Atomic Hydrogen"

In this Comment, we reanalyze the experiments on the collision frequency shift of the b-c and a-d hyperfine transitions in three-dimensional atomic hydrogen in the presence of, respectively, a and b-state atoms. Accurate consideration of the symmetry of the spatial and spin part of the diatomic wavefunction yields the difference a_T-a_S=0.30(5) \AA between the triplet and singlet s-wave scattering lengths of hydrogen atoms. This corrects the factor-of two error of the commented work [Phys. Rev. Lett. 101, 263003 (2008)].Comment: 1 pag

Legal nature of the Russian development institutions

In the article, development institution is considered from its legal form and nature, in which it can and should carry out its activities, namely, as a subject of public law. The relevance of this article is expressed by the introduction in the Russian law of a public law company concept, which is a new alternative to state-owned corporations. On July 3, 2016, Federal Law No. 236-FZ "On Public Law Companies in the Russian Federation and on Amending Certain Legislative Acts of the Russian Federation" (with amendments and additions) was adopted. After its adoption, a new wave of discussions began to take place on the active use of such concepts as a legal entity of public law in Russian legislation. At the legislative level, it became necessary to implement general principles regarding legal entities of the same type in the framework of the legal matrix, into which it is possible to attribute all known subjects of law

Metallic and insulating behaviour of the two-dimensional electron gas on a vicinal surface of Si MOSFETs

The resistance R of the 2DEG on the vicinal Si surface shows an unusual behaviour, which is very different from that in the (100) Si MOSFET where an unconventional metal to insulator transition has been reported. The crossover from the insulator with dR/dT0 occurs at a low resistance of R_{\Box}^c \sim 0.04h/e^2. At the low-temperature transition, which we attribute to the existence of a narrow impurity band at the interface, a distinct hysteresis in the resistance is detected. At higher temperatures, another change in the sign of dR/dT is seen and related to the crossover from the degenerate to non-degenerate 2DEG.Comment: 4 pages, 4 figure

Thermal compression of two-dimensional atomic hydrogen to quantum degeneracy

We describe experiments where 2D atomic hydrogen gas is compressed thermally at a small "cold spot" on the surface of superfluid helium and detected directly with electron-spin resonance. We reach surface densities up to 5e12 1/cm^2 at temperatures of approximately 100 mK corresponding to the maximum 2D phase-space density of about 1.5. By independent measurements of the surface density and its decay rate we make the first direct determination of the three-body recombination rate constant and get the value of 2e-25 cm^4/s for its upper bound, which is an order of magnitude smaller than previously reported experimental results.Comment: 4 pages, 4 postscript figures, bibliography (.bbl) file, submitted to PR

Impurity relaxation mechanism for dynamic magnetization reversal in a single domain grain

The interaction of coherent magnetization rotation with a system of two-level impurities is studied. Two different, but not contradictory mechanisms, the `slow-relaxing ion' and the `fast-relaxing ion' are utilized to derive a system of integro-differential equations for the magnetization. In the case that the impurity relaxation rate is much greater than the magnetization precession frequency, these equations can be written in the form of the Landau-Lifshitz equation with damping. Thus the damping parameter can be directly calculated from these microscopic impurity relaxation processes

Public policy and resort industry

For the past three centuries, sanatorium treatment has been an integral part of the Russian health care system. Wise use of natural resources can significantly reduce the morbidity rate, prevent many diseases, and effectively treat chronic illness. In Russia, after the reforms of the 1990s, the health resort complex was not able to immediately enter the market of services, which led to a reduction of personnel, obsolescence of material and technical base. However, nowadays, the situation is changing radically. At the moment, the state has already solved the problems of the transition period but has faced other challenges in the field of health protection of the nation. The author concludes that special attention should be paid to the further development of the industry aimed at recovering the most valuable resource - a person