Remains of chestnut wood pastures as part of agroforestry systems in Slovakia

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Properties of interstellar wind leading to shape morphology of the dust surrounding HD 61005

A structure formed by dust particles ejected from the debris ring around HD 61005 is observed in the scattered light. The main aim here is to constrain interstellar wind parameters that lead to shape morphology in the vicinity of HD 61005 using currently available observational data for the debris ring. Equation of motion of 2 $\times$ 10$^5$ dust particles ejected from the debris ring under the action of the electromagnetic radiation, stellar wind, and interstellar wind is solved. A two-dimensional (2D) grid is placed in a given direction for accumulation of the light scattered on the dust particles in order to determine the shape morphology. The interaction of the interstellar wind and the stellar wind is considered. Groups of unknown properties of the interstellar wind that create the observed morphology are determined. A relation between number densities of gas components in the interstellar wind and its relative velocity is found. Variations of the shape morphology caused by the interaction with the interstellar clouds of various temperatures are studied. When the interstellar wind velocity is tilted from debris ring axis a simple relation between the properties of the interstellar wind and an angle between the line of sight and the interstellar wind velocity exists. Dust particles that are most significantly influenced by stellar radiation move on the boundary of observed structure. Observed structure at HD 61005 can be explained as a result of dust particles moving under the action of the interstellar wind. Required number densities or velocities of the interstellar wind are much higher than that of the interstellar wind entering the Solar system.Comment: 11 pages, 7 figures, accepted to A&

Dust particles in mean motion resonances influenced by an interstellar gas flow

The orbital evolution of a dust particle captured in a mean motion resonance with a planet in circular orbit under the action of the Poynting-Robertson effect, radial stellar wind and an interstellar gas flow of is investigated. The secular time derivative of Tisserand parameter is analytically derived for arbitrary orbit orientation. From the secular time derivative of Tisserand parameter a general relation between the secular time derivatives of eccentricity and inclination is obtained. In the planar case (the case when the initial dust particle position vector, initial dust particle velocity vector and interstellar gas velocity vector lie in the planet orbital plane) is possible to calculate directly the secular time derivative of eccentricity. Using numerical integration of equation of motion we confirmed our analytical results in the three-dimensional case and also in the planar case. Evolutions of eccentricity of the dust particle captured in an exterior mean motion resonance under the action of the Poynting-Robertson effect, radial stellar wind for the cases with and without the interstellar gas flow are compared. Qualitative properties of the orbital evolution in the planar case are determined. Two main groups of the secular orbital evolutions exist. In the first group the eccentricity and argument of perihelion approach to some values. In the second group the eccentricity oscillates and argument of perihelion rapidly shifts.Comment: 13 pages, 7 figures, in v3 some text improved, submitted to MNRA

Glassy Behavior of Electrons as a Precursor to the Localization Transition

A theoretical model is presented, describing the glassy freezing of electrons in the vicinity of disorder driven metal-insulator transitions. Our results indicate that the onset of glassy dynamics should emerge before the localization transition is reached, thus predicting the existence of an intermediate metallic glass phase between the normal metal and the insulator.Comment: Six pages, one EPS figure; proceedings of EP2DS-1

Analytic model for the ballistic adsorption of polydisperse mixtures

We study the ballistic adsorption of a polydisperse mixture of spheres onto a line. Within a mean-field approximation, the problem can be analytically solved by means of a kinetic equation for the gap distribution. In the mean-field approach, the adsorbed substrate as approximated as composed by {\em effective} particles with the {\em same} size, equal to the average diameter of the spheres in the original mixture. The analytic solution in the case of binary mixtures agrees quantitatively with direct Monte Carlo simulations of the model, and qualitatively with previous simulations of a related model in $d=2$.Comment: 6 pages, RevTex, includes 2 PS figures. Phys. Rev. E (in press