1,030 research outputs found

    Recent results of the DANSS experiment

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    DANSS is a one cubic meter highly segmented plastic scintillator detector. Its 2500 one meter long scintillator strips have a Gd-loaded reflective cover. The DANSS detector is placed under an industrial 3.1GW reactor of the Kalinin Nuclear Power plant 350km NW from Moscow. The distance to the core ia varied on-line from 10.7m to 12.7m. Recent results on searches for a sterile neutrino are presented as well as measurements of the antineutrino spectrum dependence on the fuel composition. All results are preliminary. PACS: 14.60.Pq, 14.60.StComment: Talk presented at the La Thuile 2018 Conference on behalf of the DANSS Collaboration, 7 pages, 6 figure

    New results from the DANSS experiment

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    There are several experimental indications of sterile neutrinos with a mass in the 1 eV ballpark and many experiments are trying to clarify the situation. During 6 years the DANSS experiment collected more than 6 million Inverse Beta Decay (IBD) events and measured the background level during 4 reactor-off periods. Data were collected at 3 distances (10.9 m, 11.9 m, and 12.9 m) from the center of the core of a 3.1 GWth_{th} reactor with event rate up to 5 thousand per day. The detector position was changed frequently usually 2-3 times a week. Therefore many systematic uncertainties were canceled out in the analysis. After collection of additional 0.7 million IBD events the significance of the best-fit point in the 4ν\nu case increased from 1.3σ\sigma to 2.35σ\sigma. This is still not statistically significant and we present the exclusion area that covers a very interesting range of the sterile neutrino parameters up to sin22θee<0.004\sin^22\theta_{ee} < 0.004 in the most sensitive point. In particular DANSS excludes a large fraction of sterile neutrino parameters preferred by the recent BEST results including the BEST best-fit point. The IBD rate dependence on the fuel composition was measured. It agrees with predictions of the Huber-Mueller model. During almost 6 years the reactor power was measured with 1.8%\approx1.8\% accuracy in 2 days using the anti-neutrino event rate normalized to the reactor power at the initial period

    Nanometer Structured Epitaxial Films and Foliated Layers Based on Bismuth and Antimony Chalcogenides with Topological Surface States

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    The thermoelectric and galvanomagnetic properties of nanometer structured epitaxial films and foliated layers based on bismuth and antimony chalcogenides were investigated, and an increase in the figure of merit Z up to 3.85 × 10-3 K-1 was observed in the Bi0.5Sb1.5Te3 films over the temperature range of 180–200 K. It is shown that an increase in the Seebeck coefficient and the change in the slope on temperature, associated with changes in the effective scattering parameter of charge carriers and strong anisotropy of scattering in the films, lead to enhance power factor due to the growth of the effective mass of the density of states. These features are consistent with the results of research of oscillation effects in strong magnetic fields at low temperatures and research of Raman scattering at normal and high pressures in the foliated layers of solid solutions (Bi, Sb)2(Te, Se)3, in which the topological Dirac surface states were observed. The unique properties of topological surface states in the investigated films and layers make topological insulators promising material for innovation nanostructured thermoelectrics


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    The quality evaluation problem in training of students at competence-based approach is considered in the article. The technique of creation of a negentropic assessment of level of the competences formation of graduates students is offered. The article deals with the special learning curves, which provide the opportunity to be more precise in defi ning the dependence of the level of the students' competence formation of the on their scoring


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    Objective: The study of mycobacterium susceptibility to the combined application of anti-tuberculosis drugs and "Alcohol Balsam" based on beekeeping products. Methods: The anti-tuberculosis activity of ATD (anti-tuberculosis drugs) and dietary supplements "Alcohol Balsam" combination was studied in in vitro experiment in 2016. The results of swabs microscopy were assessed by the amount of bacteria within microsopic view and intensity of the "curve". The growth of MBT (mycobacterium tuberculosis) surface culture in test tubes was determined visually according to the number of colonies on the surface of the breeding ground. The research scientists tested 11, 12, 13 and 14 days’ drug effects on mycobacterium culture. Findings: In case of the main anti-tuberculosis drugs and "Alcohol Balsam" combined application, the growth of drugsensitive and multidrug-resistant strains of tuberculosis bacterium is suppressed by 100% in earlier phases compared to the anti-tuberculosis drug application alone. Conclusions: Various dilutions of ‘Alcohol balsam’ based on beekeeping products being added to the breeding ground of the first and second line anti-tuberculosis drugs increase their drugs bactericidal effects. Moreover, in earlier phases they suppress the growth of drug-sensitive and multidrug-resistant strains of tuberculosis mycobacterium in 100 % of cases. Thus, the efficacy and expediency of Galleria mellonella larvae based drugs application for human tuberculosis prevention and comprehensive treatment have been proved. Keywords: Treatment and prevention of tuberculosis; beekeeping products; Galleria mellonella larvae; Galleria mellonella; Mycobacterium tuberculosis