1,541 research outputs found

    Saturation effect and determination of nuclear matter denisity distribution from optical potential

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    A refined double folding procedure with density dependence of the effective nucleon- -nucleon interaction included is used to calculate the real part of the alpha particle — 48,40^{48,40}Ca potentials. We show that the experimentally determined difference between rms radii of the (real) potentials implies a larger size of the nuclear matter distribution of the 48^{48}Ca nucleus as compared to the 40^{40}Ca nucleus

    From spin to anyon notation: The XXZ Heisenberg model as a D3D_{3} (or su(2)4su(2)_{4}) anyon chain

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    We discuss a relationship between certain one-dimensional quantum spin chains and anyon chains. In particular we show how the XXZ Heisenberg chain is realised as a D3D_{3} (alternately su(2)4su(2)_{4}) anyon model. We find the difference between the models lie primarily in choice of boundary condition.Comment: 13 page

    Standortverhältnisse und Morphometrie von Geranium sanguineum L auf der Combe Martigny im Walliser Rhônetal, Schweiz

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    A significant larger stem height, internode number per stem, ramification number per stem, leaf-tip length, stem number/m2, leaf area indes/m2 and stem number per individual plant (polycormon) of Geranium sanguineum have been observed in forbland of the Geranio-Trifolietum alpestris as compared with forest, woodland and grassland. We summarize this in the statement that Geranium sanguineum attains its maximum vitality in forb communities. The highest presence of G. sanguineum falls within the same formation according to the referred literature.The time consuming analysis of air and soil temperature, wind velocity and plant nutrient content within the soil did not bring in the expected decisive site factor(s) in the vegetation catena forest-forbland-grassland. According to earlier “holistic” field observations the lower vitality and lower presence of G. sanguineum in forest as compared with forbland may be caused by the light factor. The absence of G. sanguineum in the majority of the dry grasslands in the research area may be due to excessive drainage of the site or/and present or former mowing or grazing.The higher vitality of G. sanguineum within the forb communities has been observed in the forest bordering type. The decisive site factor is here, following Dierschke, the intermittent sunlight along the forest edge.Guidelines for the classification of the Geranio-Trifolietum alpestris (in Quercetea pubescentipetraeae, Trifolio-Geranietea or Festuco-Brometea) cannot be derived from the sampled microclimatic and edaphic parameters. The statements of both Jakucs (1972) and Dierschke (1974) about this question turned out to be valid locally only
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